Source: TEXAS A&M UNIVERSITY submitted to NRP
ENHANCEMENT OF ARACHIS GERMPLASM TO IMPROVE PEANUT (A. HYPOGAEA L.) CULTIVARS
Sponsoring Institution
National Institute of Food and Agriculture
Project Status
COMPLETE
Funding Source
HATCH
Reporting Frequency
Annual
Accession No.
0096438
Grant No.
(N/A)
Cumulative Award Amt.
(N/A)
Proposal No.
(N/A)
Multistate No.
(N/A)
Project Start Date
Sep 10, 2007
Project End Date
Sep 9, 2013
Grant Year
(N/A)
Program Code
[(N/A)]- (N/A)
Recipient Organization
TEXAS A&M UNIVERSITY
750 AGRONOMY RD STE 2701
COLLEGE STATION,TX 77843-0001
Performing Department
Stephenville-TAMU Agr Res Cntr
Non Technical Summary
Resistance to many diseases, insects, and nematodes that affect peanut is not found in the cultivated species. This project utilizes the wild Arachis species germplasm to enhance the genetic variability of the cultivated species for resistances and stress tolerance. The work is to be enhanced by the use of molecular tools (Maps) and marker assisted selection. The purpose of this project is to provide the peanut growers of Texas with improved cultivars of peanut to meet the demands they have for remaining competitive in the developing global economy. The purpose of this project is to develop pathways to transfer genes from wild peanut species into the cultivated, then to actually make the transfer of genes that we or other projects identify.
Animal Health Component
(N/A)
Research Effort Categories
Basic
(N/A)
Applied
(N/A)
Developmental
(N/A)
Classification

Knowledge Area (KA)Subject of Investigation (SOI)Field of Science (FOS)Percent
2011830108020%
2021830108040%
2021830108120%
2121830108120%
Knowledge Area
212 - Pathogens and Nematodes Affecting Plants; 202 - Plant Genetic Resources; 201 - Plant Genome, Genetics, and Genetic Mechanisms;

Subject Of Investigation
1830 - Peanut;

Field Of Science
1081 - Breeding; 1080 - Genetics;
Goals / Objectives
1. Determine crossability and cross compatibility characteristics of Arachis species and their accessions through collaborative studies, conduct cytological, molecular, and molecular cytogenetic studies (Jewell and Faridi, 1994) of the accessions and their hybrids. 2. Identify useful genetic traits contained in the Arachis germplasm and, through collaborative efforts, correlate these characters with molecular markers. This effort will also include providing field data on traits for the tetraploid molecular map and finish making the fifth backcrosses of the mapping population to further develop the population of near-isogenic lines for introgression studies. 3. Incorporate useful genetic traits into germplasm breeding lines, which can be utilized in cultivar development programs; including conventional methods and, through collaborative studies, non conventional techniques such as tissue culture, and DNA markers . 4. Assist in developing improved cultivars of peanut utilizing enhanced germplasm resources with resistance to leafspot, nematodes, pod rot, southern blight, and sclerotinia with early maturity, high oil content, and high O/L ratio. These will be resources developed in objective 3 and materials by the projects at Lubbock (Dr. M.D. Burow) and College Station (M.R. Baring). 5. Evaluate new cultivars and germplasm collections for use in the Texas environments, specifically searching for drought tolerance, leafspot, nematode, southern blight, sclerotinia blight, and pod rot resistance. 6. Continue to maintain and evaluate the germplasm collection, both cultivated and wild species, and multiply seed resources for the program when necessary. 7. Collect new germplasm resources as the needs and opportunities arise.
Project Methods
1. Standard methods of cross pollinating peanut plants will be used in the determination of crossing potential and cross compatibility of species and accessions (Norden, 1980). We also will utilize a new (to us) crossing technique adapted from our colleagues in West Africa that yields more than 95% successes in easy crosses. Pollen counts, meiotic studies, and molecular cytogenetic techniques will be used in determining phylogenetic relationships of various parents and hybrids. We will also utilize the molecular genetic map generated by collaboration between this and Dr. Burows project, and as the map expands we will utilize those additions. Crossing data will aid us in selection of parents for crossing as well as for describing new species which have been collected in South America over the past 30 years. Also to identify additional pathways for the transfer of genes from wild peanut species into the cultigen. We plan to continue to collaborate with the program at EMBRAPA/CENARGEN in Brazil in this important work. 2. We will screen and evaluate materials in search for useful traits to be introgressed into cultivated lines. These efforts will include traditional screening as well as use of molecular markers now known or to be developed in the future. We will be actively involved in the search for molecular markers for various traits, including Tomato Spotted Wilt Virus (TSWV), sclerotinia blight, southern blight, leaf spot, rust, and some nematode species, as well as quality traits and early maturity. 3. Crossing and backcrossing (Simpson, 1991) and utilizing molecular markers (Cason, 2001) will be our most valuable tool for introgressing genes into A. hypogaea. As mentioned above we will be actively involved in the molecular marker search by providing plant materials and evaluating developed lines. 4. As genes are incorporated into improved lines we will begin evaluation and testing to determine if we have developed materials which will be useful as cultivars for our cliental. 5. Our testing program has been extensive for many years so that we are able to evaluate advancing lines from the Texas program as well as lines and released cultivars from other peanut breeding programs in the US and world. Standard techniques of field-testing will be utilized in these replicated tests and statistical analyses will be the basis of decisions on yield levels, etc. 6. We will constantly be searching for new ways of evaluating our breeding materials to best determine which lines have the desired traits. This in turn will carry us forward in the identification of new traits that need to be incorporated into our new cultivars. 7. Collection of new materials, especially in South America has become very difficult and in many cases impossible. Permits for collection are not possible in Brazil, Peru, and Bolivia at the present time. Severe limits exist in Argentina and other countries, and the only country where we can collect and export germplasm to the USA is from Paraguay.

Progress 09/10/07 to 09/09/13

Outputs
Target Audience: Peanut Breeders and Geneticists, Peanut Commodity Groups, Peanut Growers, Other Peanut Research and Extension personnel. Changes/Problems: New project with same objectives is underway. What opportunities for training and professional development has the project provided? We initiated the Science without Borders program by having a PhD student come for training in cross pollination and hybrid development in our program. How have the results been disseminated to communities of interest? Varieties released to public, data provided to colleagues, papers presented at scientific meetings. What do you plan to do during the next reporting period to accomplish the goals? This is a final report.

Impacts
What was accomplished under these goals? Goal 1: We accomplished more than 30 new interspecific hybrids in this reporting period. We also re-made several previously accomplished hybrids for molecular study. We continued the A genome mapping population study with Dr. Burow in Lubbock, providing him F2 seed for evaluation, then taking those seed to plant for the SSD generation one. We initiated the B genome mapping population development. Goal 2:We identified a new source of insect resistance in some of our introgression hybrid populations. Goal 3: We continued the efforts on introgression of southern blight resistance into cultivated peanut. We continued the introgression of high oil content into breeding lines and combined this trait with the high O/L trait. Goal 4 & 5: The Sclerotinia screening was continued on introgressed lines with leafspot resistance, others with nematode resistance, and others with both. Goal 6:We maintained 99.8 % of the germplasm collection under our care. Goal 7: We accomplished an agreement with Brazil in their "Science without Borders" program for the next threeyears where we will train students from Brazil and this PI will make 2 month visits to Brazil for training, research, and germplasm recovery.

Publications

  • Type: Journal Articles Status: Published Year Published: 2013 Citation: Simpson, C.E., J.L. Starr, M.R. Baring, M.D. Burow, J.M. Cason, and J.N. Wilson. 2013. Registration of Webb Peanut. Journal of Plant Registrations. Vol 7 #3: 265-268. doi 10.3198/jpr2013.01.0005crc
  • Type: Journal Articles Status: Published Year Published: 2013 Citation: Baring, M.R., C.E. Simpson, M.D. Burow, J.M. Cason and J.L. Ayers. 2013. Registration of Tamrun OL11 Peanut. Journal of Plant Registrations 7 #2: 154-158. doi 10.3198/jpr2012.06.0001crc.
  • Type: Journal Articles Status: Published Year Published: 2013 Citation: Krapovickas, A., R.O. Vanni, J.R. Pietrarelli and C.E. Simpson. 2013. Las razas de mani de Peru. (The rases of peanut of Peru). Bonplandia 22 #1: 19  90. ISSN 0524-0476.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2013 Citation: Burow, M.D., J.L. Starr, C.E. Simpson, C-H. Park, A.H. Paterson. 2013. Identification of Orthologous QTLs for Resistance to the Root-knot Nematode (Meloidogyne arenaria (Neal) Chitwood) in Peanut (Arachis hypogaea L. Presentation at the APRES annual meeting in Young Harris, Georgia, July 8-11, 2013.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2013 Citation: Simpson, C.E., J.L. Starr, M.R. Baring, M.D. Burow, J.M. Cason, J.N. Wilson. 2013. Webb, a New High Oleic and Rootknot Nematode Resistant Runner Peanut. Presentation at the APRES annual meeting in Young Harris, Georgia, July 8-11, 2013.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2013 Citation: Baring, M.R., J.N. Wilson, C.E. Simpson, and J.M. Cason. Correlations Between Leafspot Resistance, Sclerotinia Resistance, Yield, Total Sound Mature Kernels, and O/L Values in a Segregating F2 Derived Peanut Population. Presentation at the APRES annual meeting in Young Harris, Georgia, July 8-11, 2013.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2013 Citation: Chopra, R., G. Burow, A. Farmer, J. Mudge, C.E. Simpson, T.A. Wilkins, and M.D. Burow. 2013. Massively Parallel Transcriptome Sequencing of Eighteen Cultivatee and Wild Peanuts for SNP Discovery. Presentation at the APRES annual meeting in Young Harris, Georgia, July 8-11, 2013.
  • Type: Other Status: Published Year Published: 2013 Citation: Abstract Published: Burow, M.D., J.L. Starr, C.E. Simpson, C-H. Park, A.H. Paterson. 2013. Identification of Orthologous QTLs for Resistance to the Root-knot Nematode (Meloidogyne arenaria (Neal) Chitwood) in Peanut (Arachis hypogaea L. Proceedings of the APRES annual meeting in Young Harris, Georgia, July 8-11, 2013. Vol. 45. Page 29.
  • Type: Other Status: Published Year Published: 2013 Citation: Abstract Published:Simpson, C.E., J.L. Starr, M.R. Baring, M.D. Burow, J.M. Cason, J.N. Wilson. 2013. Webb, a New High Oleic and Rootknot Nematode Resistant Runner Peanut. Proceedings of the APRES annual meeting in Young Harris, Georgia, July 8-11, 2013. Vol. 45. Page 30
  • Type: Other Status: Published Year Published: 2013 Citation: Baring, M.R., J.N. Wilson, C.E. Simpson, and J.M. Cason. Correlations Between Leafspot Resistance, Sclerotinia Resistance, Yield, Total Sound Mature Kernels, and O/L Values in a Segregating F2 Derived Peanut Population. Proceedings of the APRES annual meeting in Young Harris, Georgia, July 8-11, 2013. Vol. 45. Page 38
  • Type: Other Status: Published Year Published: 2013 Citation: Abstract Published:Chopra, R., G. Burow, A. Farmer, J. Mudge, C.E. Simpson, T.A. Wilkins, and M.D. Burow. 2013. Massively Parallel Transcriptome Sequencing of Eighteen Cultivatee and Wild Peanuts for SNP Discovery. Proceedings of the APRES annual meeting in Young Harris, Georgia, July 8-11, 2013. Vol. 45. Page 42.


Progress 01/01/12 to 12/31/12

Outputs
OUTPUTS: Project lead the release of one new cultivar (Webb), and participated in the release of two more new cultivars (Tamrun OL12 and Schubert) during this reporting period. Webb is the first nematode resistant (Meloidogyne arenaria [in italics]), high oleic runner peanut variety developed from the program designed to introgress nematode resistance from a wild peanut species (Arachis cardenasii; in italics) into cultivated peanut. This is the third variety release from the introgression program. Tamrun OL12 is an early maturing, high oleic runner peanut cultivar that is at least 10 days earlier maturing than any other commercially available runner variety. Schubert is an early maturing, high oleic Spanish peanut cultivar that is about 10 days earlier than the OLin peanut variety and is higher yielding than OLin. Selection of two lines that appeared to have Sclerotium rolfsii (in italics) resistance were selected for backcrossing to the cultivated parent. Two years of field testing indicated that additional cultivated peanut genetics were needed to realize selection progress for resistance in this introgression program. Parentage of this program has been reported previously. Crosses were made between the recently chromosome doubled amphiploids in the high oil percentage introgression program. The amphiploids will be maintained for additional crossing efforts. Additional crosses were made between the drought tolerant species and the bridge species that is in the Arachis (in italics) section. Eighteen crosses were made in our cross compatibility studies in which we are developing information for describing additional new species of the genus Arachis (in italics). Progenies from some of these crosses will also be used in developing additional introgression pathways for improvement of the cultivated peanut. Eleven tests were conducted in screening for Sclerotina minor (in italics) resistance. Three screening tests were composed of runner type leafspot resistant lines; four tests were composed of early maturing runner breeding lines; one test was composed of rootknot resistant runner breeding lines; one test was composed of our advanced runner breeding lines; one test was composed of F7 Virginia breeding lines. Three yield tests were conducted to determine relative yield potential of various breeding lines as compaired to check cultivars without Sclerotina pressure. PARTICIPANTS: The collaborators on the project are those listed on the title page with one exception: A.M. Schubert is now deceased. Others are M.D. Burow, M.R. Baring, M.C. Black, J.L. Starr, and J.M. Cason. Also, J. Woodward collaborates on the project. We also collaborate with several international scientists in Senegal, Burkina Faso, Argentina, Bolivia and Brazil. Our funding has come from Chevron Corp., Texas Peanut Producers Board, National Peanut Board, and the Peanut Collaborative Research Support Project which is a part of the USAID in the State Department. During the year we had two research scientists from West Africa to come for training in developing a Foundation Seed program for peanut in Senegal and Burkina Faso. TARGET AUDIENCES: The target audiences for our efforts are several fold: The yield data from variety trials is targeted to producers, extension specialists and consultants; the target audience for our more basic type work is fellow research scientists to further the science of peanut breeding, genetics, germplasm enhancement, and the taxonomy of the genus Arachis (in italics). PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.

Impacts
The release of the Webb variety could help bring a part of 165,000 acres of highly productive peanut soils in Central Texas back into production, with a potential of adding multi-millions of dollars of farm income to these growers. Webb will also provide a profitable variety for growers in South Texas who have parts or all their farms infested with root-knot nematodes. The potential here is in the 3 to 5 million dollar range per year. Foundation seed of Webb will be produced in 2013 and certified seed will be available in 2015. The early maturing Tamrun OL12 and Schubert varities are in the breeder seed increase stage and are 2 or 3 years away from farmer use. Both varieties hold great potential for increasing farmer income. The high oil materials we are working with continue to move forward. We were successful in crossing the introgression amphiploid with a cultivated variety and we will be making backcrosses and seed increase on these complex hybrids. We have not been successful to date on the crosses between the drought tolerant wild species and the bridge species, but we anticipate success on the cross, even if we must use embryo rescue efforts. We were successful in making some compatibility crosses that will help us in describing additional new species of the genus Arachis (in italics). Selections from the eleven screening tests for resistance to Sclerotina will be carried forward in yield testing, crossing studies, or genetic studies.

Publications

  • Cason, J.M., B.D. Bennett, and C.E. Simpson. 2012. Germination and Emergence effect on Peanut seed planted directly from cold storage. 44th Annual Meeting-American Peanut Research and Education Society. July 10-12. Raleigh, N.C. USA.
  • Baring, M.R., J.N. Wilson, W.L. Rooney, C.E. Simpson, and J.L. Starr. 2012. Diallel Analysis of Oil Content in Peanut. 44th Annual Meeting-American Peanut Research and Education Society. July 10-12. Raleigh, N.C. USA.
  • Wilson, J.N., M.R. Baring, M.D. Burow, W.L. Rooney, C.E. Simpson, J.L. Starr,, and J.C. Chagoya. 2012. Generations Means Analysis of Oil and Fatty Acid Content in Peanut. 44th Annual Meeting-American Peanut Research and Education Society. July 10-12. Raleigh, N.C. USA. Woodward, J.E., C.E. Simpson, M.R. Baring, and T.A. Baughman. 2012. Evaluation of Tamrun OL11 under Varying Field Conditions. 44th Annual Meeting-American Peanut Research and Education Society. July 10-12. Raleigh, N.C. USA.
  • Chopra, R., G. Burow, A. Farmer, J. Mudge, I. Lindquist, G. D. May, M.S. Gomez, Z. Xin, C. Simpson, N. Puppala, K. D. Chamberlin, T. Wilkins, and M. D. Burow. 2012. Genome-wide Assessment of SNPs in Peanut Using Illumina (Solexa) Sequencing. Plant and Animal Genome Meeting, Jan. 14-18, 2012. San Diego, CA.
  • Simpson, C.E. 2012. Breeding Peanut, Chapter 36, pp 639-646. IN. Principles of Plant Genetics and Breeding. George Acquaah, Ed. ISBN 978-0470-66476-6. 758 pp. John Wiley & Sons, Inc. Hoboken N.J. 07030, USA
  • Burow, M.D., J.L. Ayers, A. Muitia, A.M. Schubert, Y. Lopez, C.E. Simpson, N. Puppala, and M.R. Baring. 2012. Development of High-Yielding, High Oleic Valencia Peanuts. An Abstract. American Peanut Research and Education Society Proceedings. Vol. 44: .
  • Cason, J.M., B.D. Bennett, and C.E. Simpson. 2012. Germination and Emergence effect on Peanut seed planted directly from cold storage. An Abstract. American Peanut Research and Education Society Proceedings. Vol. 44: .
  • Melouk, H.A, K. Chamberlin, C.B. Godsey, J. Damicone, M.D. Burow, M.R. Baring, C.E. Simpson, K.E. Dashiell, M. Payton. 2012. Journal of Plant Registrations 10.3198/jpr2012.03.0174crc.
  • Rowland, D., N. Puppala, J. Beasley Jr., M. Burow, D. Gorbet, D. Jordan, M. Melouk, C. Simpson, J. Bostick, and J. Ferrell. 2012. Variation in carbon isotope ratio and its relation to other traits in peanut breeding lines and cultivars from U.S. trials. Journal of Plant Breeding and Crop Science 4(9):144-155.
  • Baring, M.R., J.N. Wilson, W.L. Rooney, C.E. Simpson, and J.L. Starr. 2012. Diallel Analysis of Oil Content in Peanut. Poster. American Peanut Research and Education Society Proceedings. Raleigh, NC. July 12-14, 2012.
  • Wilson, J.N., M.R. Baring, M.D. Burow, W.L. Rooney, C.E. Simpson, J.L. Starr, and J.C. Chagoya. 2012. Generations Means Analysis of Oil and Fatty Acid Content in Peanut. An Abstract. American Peanut Research and Education Society Proceedings. Vol. 44: .
  • Woodward, J.E., C.E. Simpson, M.R. Baring, and T.A. Baughman. 2012. Evaluation of Tamrun OL11 under Varying Field Conditions. An Abstract. American Peanut Research and Education Society Proceedings. Vol. 44: .
  • Chopra, R., G. Burow, A. Farmer, J. Mudge, I. Lindquist, G. D. May, M.S. Gomez, Z. Xin, C. Simpson, N. Puppala, K. D. Chamberlin, T. Wilkins, and M. D. Burow. 2012. Genome-wide Assessment of SNPs in Peanut Using Illumina (Solexa) Sequencing. Plant and Animal Genome Meeting 2012, Poster P0203. Jan. 14-18, 2012. San Diego, CA.
  • Burow, M.D., J.L. Ayers, A. Muitia, A.M. Schubert, Y. Lopez, C.E. Simpson, N. Puppala, and M.R. Baring. 2012. Development of High-Yielding, High Oleic Valencia Peanuts. 44th Annual Meeting-American Peanut Research and Education Society. July 10-12. Raleigh, N.C. USA.


Progress 01/01/11 to 12/31/11

Outputs
OUTPUTS: Project participated in two cultivar releases since last report. The new runner peanut, Tamrun OL11 was released by Texas AgriLife Research. This peanut is high yielding, high grading, high Oleic acid and excellent shelling and roasting characteristics. The second release was joint between Texas AgriLife Research and USDA-ARS. The runner peanut, Red River Runner, is high grading and equal yield to Tamrun OL07. The seed increase of the multi-trait breeding line with potential for release, PR-2, was a victim of the severe drought of 2011 in Texas. The breeder seed increase will have to be repeated in 2012. The application for release will also occur in 2012. This line has excellent rootknot nematode resistance [Meloidogyne arenaria (in italics) and M. javanica (in italics)], it has a high Oleic acid: Linoleic acid ratio (>20:1), it has high yield and grade, and a moderate level of resistance to sclerotinia blight [Sclerotinia minor (in italics)]. We continue to search for funding for the next steps for the backcross 5 materials in a molecular mapping/breeding/peanut variety development program. A second year of field testing was conducted on an interspecific hybrid population where we were screening for southern blight [Sclerotium rolfsii (in italics)] resistance in our introgression program. From the first 1,500 plants we selected 72 F3 plants for re-evaluation on a single plant basis and 24 were planted as plant-rows. These plants were developed from a new introgression pathway that we have developed involving two A genome diploid species, one B genome diploid species, and the tetraploid cultivated species. Two lines were selected from the plant rows for backcrossing to the cultivated recurrent parent. The other materials were placed in storage. Two other introgression pathways for the high oil trait were carried forward by making three attempts to double chromosome numbers on tri-species complex hybrids involving the high oil donors and two bridge species. The plants are being evaluated at this writing to determine results. A fourth introgression pathway involving two species outside the cultivated section had a successful chromosome doubling and the tetraploid (2n=4x=40) hybrid is being evaluated. A fifth introgression pathway was initiated during this period in an attempt to transfer drought tolerance into the cultivated peanut. Three other introgression pathways are in the planning stage and will involve four diploid species which contain unidentified genomic makeup crossed with either A, B, F, or K genomes and/or combinations of these four. Other probe crosses will be made as we work on background information that is needed to describe several new putative wild Arachis (italics) species. Chromosome doubling of certain hybrids will continue as hybrids are developed. PARTICIPANTS: The collaborators on the project include those listed on the title page: M.D. Burow, M.R. Baring, M.C. Black, and J.L. Starr. J.M. Cason, Research Associate and B.D. Bennett, Greenhouse Technician, as well as one undergraduate student who also worked on the project. We collaborate with several research scientists in Argentina, Brazil and Bolivia as well as Senegal and Burkina Faso. Our funding partners include the Tesas Peanut Producers Board and the National Peanut Board. We have also partnered with Chevron. I tried last year to have Dr. A.M. Schuberts name removed from the project because he died, but the removal did not happen. TARGET AUDIENCES: The target audiences for our efforts are several fold: The yield data from variety trials is targeted to producers, extension specialists and consultants; The target audience for our more basic type work is fellow research scientists to further the science of peanut breeding, genetics, germplasm enhancement, and the taxonomy of the genus Arachis (in italics). PROJECT MODIFICATIONS: We will be moving more away from the applied variety development part of the peanut breeding program and more to the germplasm enhancement in an effort to enrich the program with the many valuable genes within the wild peanut species.

Impacts
The PR-2 breeding line, as a cultivar, has the potential to bring several thousand acres of prime peanut soil back into production in the historical peanut growing counties of Texas. The acceptance of a recent release, Tamrun OL11, is anticipated because shellers and growers both like the preliminary results. Also, acceptance of other two recent releases, Tamnut OL06 and Tamrun OL07 continues to grow. It is apparent that these two cultivars are providing peanut growers an advantage with added production and, thus profits. Funding is needed to continue the molecular mapping program to develop near isogenic lines using the 297 BC5 populations that have been developed. This project has a large potential to make prescription breeding of cultivated peanut a reality. The development of a peanut cultivar that is resistant to southern blight would be a significant breakthrough in increasing production and reducing cost thereof as well as cutting chemical application to the environment. Other introgression pathways involve other disease resistances, quality traits, drought tolerance, and oil percentage.

Publications

  • Gomez, S.M., C.E. Simpson, P.B. Vikas, H. Patel, A.H. Paterson, and M.D. Burow. 2011. Proceedings American Peanut Research and Education Society. 43: 83-84 (An abstract).
  • Burow, M.D., C.E. Simpson, M.W. Faries, J.L. Starr, and A.H. Paterson. 2009. Molecular biogeographic study of recently described B- and A-genome Arachis (in italics) species, also providing new insights into the origins of cultivated peanut. Genome 52: 107-119.
  • Simpson, C.E., M.D. Burow, and J.L. Starr. 2011. Developing Introgression Pathways for Gene Transfer to Arachis hypogaea (in italics) L. Invited paper to: 5th Advances in Arachis (in italics) through Genomics and Biotechnology 2011. Page 16, Book of Abstracts. http://www.cenargen.embrapa.br/aagb2011/. June 13-17, 2011. Brasilia DF, Brazil.
  • Simpson, C.E., M.D. Burow, M.R. Baring, and J.L. Starr. 2011. Utilizing the Arachis (in italics) Wild Species Collection for Improving the Cultivated Peanut: Introduction and History. Proceedings American Peanut Research and Education Society. 43: 85-86 (Invited Symposium, An abstract).
  • Baring, M.R., C.E. Simpson, and M.D. Burow. 2011. Introgression of Early Leafspot Resistance from Wild Species into the Cultivated Peanut Arachis hypogaea (in italics). Proceedings American Peanut Research and Education Society. 43: 90 (Invited Symposium, An abstract).
  • Burow, M.D., C.E. Simpson, J.L. Starr, C.H. Park, A.H. Paterson. 2011. Identification of Domestication-Associated QTLs Introgressed into Cultivated Peanut, (Arachis hypogaea (in italics) L.) Proceedings American Peanut Research and Education Society. 43: 90-91 (Invited Symposium, An abstract).
  • Baring, M.R., J.N. Wilson, C.E. Simpson, and J.M. Cason. 2011. Segregation of an F2 Derived Population for Leafspot Resistance. Proceedings American Peanut Research and Education Society. 43: 44 (A poster).
  • Chopra, R., S. Swaroop, G. Burow, Z. Xin, S.M. Gomez, A. Farmer, G. May, C.E. Simpson, N. Puppala, T.A. Wilkins, and M.D. Burow. 2011. Next Generation Transcriptome Sequencing of the High Oleic Peanut Cultivar Olin and Identification of SNPs Between Cultivars. Proceedings American Peanut Research and Education Society. 43: 53 (A poster).
  • Wilson, J.N., M.R. Baring, M.D. Burow. C.E. Simpson, W.L. Rooney, J.L. Starr. 2011. Generation Means Analysis of Oil Content in Peanut. Proceedings American Peanut Research and Education Society. 43: 60-61 (A poster).
  • Cason, J.M., B.D. Bennett, and C.E. Simpson. 2011. Germination and Emergence Effects on Peanut Seed Planted Directly from Cold Storage. Proceedings American Peanut Research and Education Society. 43: 80 (An abstract).
  • Burow, M.D., J.L. Ayres, A. Muitia, A.M. Schubert, Y. Lopez, C.E. Simpson, N. Puppala, and M.R. Baring. 2011. Development of High-Yielding, High-Oleic, Early-Maturing Spanish Peanuts. Proceedings American Peanut Research and Education Society. 43: 81 (An abstract).
  • Denwar, N.N. C.E. Simpson, J.L. Starr, T.A. Wheeler, J.L. Ayers, M.R. Baring, S.K. Nutsugah, P. Sankara, and M.D. Burow. 2011. Evaluation of Interspecific Lines and Breeding Populations of Arachis hypogaea (in italics) L. for Yield and Resistance to Leaf spot Diseases in Ghana and Texas. Proceedings American Peanut Research and Education Society. 43: 81-82 (An abstract).


Progress 01/01/10 to 12/31/10

Outputs
OUTPUTS: The quality analyses conducted on a multi-trait breeding line with potential for release, PR-2, and related yield and grade analyses provided sufficient confirmation for a decision to submit the line for evaluation for release as a new cultivar. This line has excellent rootknot nematode resistance [Meloidogyne arenaria (in italics) and M. javanica (in italics)], it has a high Oleic acid: Linoleic acid ratio (>20:1), it has high yield and grade, and a moderate level of resistance to sclerotinia blight [Sclerotinia minor (in italics)]. All of the backcross fives have been completed, DNA samples collected and seed multiplied in the program to develop near isogenic lines for prescription breeding in the cultivated peanut. We continue to search for funding for the next steps in this molecular mapping/breeding/peanut variety development program. Field testing was conducted on an interspecific hybrid population where we were screening for southern blight [Sclerotium rolfsii (in italics)] resistance in our introgression program. These ca. 1,500 plants were developed from a new introgression pathway that we have developed involving two A genome diploid species, one B genome diploid species, and the tetraploid cultivated species. These lines were advanced by single seed descent for further evaluation of F3 material. Three other introgression pathways are in the intermediate stages of development which involve five diploid species which contain unidentified genomic makeup crossed with either A, B, F, or K genomes and/or combinations of these latter four. Chromosome doubling of certain hybrids will continue as putative hybrids are developed. PARTICIPANTS: The collaborators on the project include those listed on the title page: M.D. Burow, M.R. Baring, M.C. Black, and J.L. Starr. J.M. Cason, Research Associate and B.D. Bennett, Greenhouse Technician, as well as three undergraduate students also worked on the project. TARGET AUDIENCES: The target audiences for our efforts are several fold: The yield data from variety trials is targeted to producers, extension specialists and consultants; The target audience for our more basic type work is fellow research scientists to further the science of peanut breeding, genetics, molecular genetics, germplasm enhancement, and the taxonomy of the genus Arachis (in italics). PROJECT MODIFICATIONS: The only project modification this period is to remove Dr. A.M. Schubert as a collaborator. His untimely death has left a void in our quality analysis work.

Impacts
The PR-2 breeding line, as a cultivar, has the potential to bring several thousand acres of prime peanut soil back into production in the historical peanut growing counties of Texas, as well as other states. The application for release is pending at this time, but completion and submission are anticipated soon.The acceptance of two recent releases, Tamnut OL06 and Tamrun OL07 has been gratifying. It is apparent that these two cultivars are providing peanut growers an advantage with added production and, thus profits. Funding is needed to continue the molecular mapping program to develop near isogenic lines using the 297 BC5 populations that have been developed. This project has a large potential to make prescription breeding of cultivated peanut a reality. The development of a peanut cultivar that is resistant to southern blight would be a significant breakthrough in increasing production and reducing cost thereof as well as cutting chemical application to the environment. Other introgression pathways involve other disease resistances, quality traits and oil percentage.

Publications

  • Krapovickas, A., Ricardo O. Vanni, Jose R. Pietrarelli, David E. Williams and Charles E. Simpson. 2009. Las Razas de Mani de Bolivia (The Races of Peanut of Bolivia). Bonplandia XVII #2: 1-189
  • Lavia, G.I., A. Fernandez, C.E. Simpson, and G. Seijo. 2001. Meiotic Analysis in Wild Diploid Arachis (in italics) Species. Cytologia 66: 287-291.
  • Simpson, C.E., J.M. Cason, B.D. Bennett. 2010. Update on the Long Term Storage of Arachis (in italics) Seeds. Proceedings American Peanut Research and Education Society. 42: 84-85 (An abstract).
  • Simpson, C.E. 2010. Pre-breeding and Breeding Arachis (in italics) for Protection from Biotic Stresses: Cercospora/Cercosporidium Spp., Puccinia arachidis, Meloidogyne Spp., Sclerotium rolfsii (all in italics). Invited Paper to the Fifth International Legume Conference: Advances in the XXI Century and VII International Arachis (in italics) Specialists meeting. Buenos Aires, Argentina August 8-14, 2010. www.leguminosae.com.ar.
  • Baring, M.R., J.N. Wilson, C.E. Simpson, J.M. Cason, M.D. Burow and J.L. Ayers. 2010. Variability of Total Oil Content in Peanut Across the State of Texas II. Proceedings American Peanut Research and Education Society. 42: 50-51. (An abstract).
  • Starr, J.L., M.R. Baring, C.E. Simpson and J.M. Cason. 2010. Multiple Disease Resistance in High O/L Peanuts. Proceedings American Peanut Research and Education Society. 42: 75 (An abstract).
  • Burow, M.D., J.L. Ayers, A.M. Schubert, C.E. Simpson, M.R. Baring. 2010. Characterization of Early-Maturing Peanut Breeding Lines. Proceedings American Peanut Research and Education Society. 42: 78 (An abstract).


Progress 01/01/09 to 12/31/09

Outputs
OUTPUTS: Quality analyses on the three multi-trait breeding lines mentioned last year revealed that all three were acceptable in chemical and flavor aspects. These lines have resistance to root knot nematode [Meloidogyne arenaria (in italics) and M. javanica (in italics)], sclerotinia blight [Sclerotinia minor (in italics), tomato spotted wilt virus (TSWV), as well as being high in Oleic/Linoleic acid ratio. The statewide advanced lines yield test data for 2008 showed that one breeding line was superior in yield, however, a test to determine purity for nematode resistance was negative so we will consider an older breeding line with better sound mature kernel turn-out but slightly lower yield as a potential line for release. Several new lines show potential but only have preliminary yield data at present. Quality analyses will need to be conducted on these lines as well. Another year of yield tests give additional confirmation that the new varieties, Tamnut OL06 and Tamrun OL07, outperform other varieties in their important aspects of early maturity and disease resistance. The information from these tests will be shared with extension specialists as well as reported to the Texas Peanut Producers Board, the funding agency that made the work possible. The nine hybrid populations made between a high oil content interspecific breeding line and selected high yielding, disease resistant commercial varieties to develop breeding populations high in oil content have now been advanced to the backcross two generation. An additional 85 backcross-five crosses were made from the 630 backcross 4 populations in our effort to construct a tetraploid molecular map and to develop a series of near isogenic lines which would allow us to do prescription breeding of peanut populations. All of these crosses have been completed and DNA material collected from all 297 male parents from backcross-four origin. Analyses of the DNA will tell us which crosses to follow-up with and which to discard. Seed was increased on an interspecific hybrid plant with putative resistance to Sclerotium rolfsii (in italics) which was crossed with a high yielding commercial cultivar with multi-traits mentioned above. Additional crosses, multiple crosses and backcrosses were made in attempts to develop new pathways for introgression of genes from wild Arachis (in italics) species into the cultigen, A. hypogaea. Numerous traits are under study and are involved in these crosses at various levels. Some of the traits are at the first cross level, some are at the second or multiple cross level, others are at the backcross level, and still others are at the colchicine/chromosome doubling level. PARTICIPANTS: The collaborators on the project include those listed on the title page: M.D. Burow, M.R. Baring, A.M. Schubert, M.C. Black, and J.L. Starr. J.M. Cason, Research Associate and B.D. Bennett, Greenhouse Technician, as well as four undergraduate students also worked on the project. TARGET AUDIENCES: The target audiences for our efforts are several fold: The yield data from variety trials is targeted to producers, extension specialists and consultants; The target audience for our more basic type work is fellow research scientists to further the science of peanut breeding, genetics, germplasm enhancement, and the taxonomy of the genus Arachis (in italics. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.

Impacts
A new seed increase will be made on the older multi-trait line with nematode resistance in 2010. The decision to release as a new cultivar is still pending analysis of the 2009 yield data and quality analyses. The release of such a cultivar could bring several thousand acres of choice peanut growing soil back into production. This would have a significant impact on the economy of those counties affected. Potential for Tamnut OL06 and Tamrun OL07 to make a strong contribution to the economy of the peanut growing counties of South and West Texas continues to look very promising. Molecular analyses of the backcross five populations will tell us which of the hybrid populations to multiply for further evaluation. The impact of a molecular map constructed from such data and a population of near isogenic lines could be significant in future peanut breeding efforts. Resistance to Sclerotium rolfsii (in italics) would be very important to the peanut industry, saving growers millions of dollars in chemical costs, improving yields, lowering chemical content of peanut products, and putting less chemical residue into the environment. The several introgression pathways that we are working on are in varying levels of development, as mentioned in Outputs. As an individual pathway is completed it will have an impact on realizing the trait within the cultivated peanut. If the trait is resistance to some disease, it could make an impact very soon in the form of a new cultivar released that is resistant to the disease. We are still evaluating the impact of the MS Thesis project that studied the seed size in relationship to the distance from the main axis that the seed is set.

Publications

  • Baring, M.R., Burow, M.D., Simpson, C.E. and Wilson, J.N. 2009. Variability of Total Oil Content in Peanut across the State of Texas. American Peanut Research and Education Society - Proceedings. 41: . An abstract.
  • Woodward, J.E., Ratliff, M.L., Yates, J.I., Simpson, C.E. and Baughman, T.A. 2009. Effects of Fungicides and Cultivar Selection on Sclerotinia Blight of Peanut in Texas. American Peanut Research and Education Society - Proceedings. 41: . An abstract.
  • Pattee, H.E., Isleib, T.G., Gorbet, D.W., Sanders, T.H., Dean, L.L. and Hendrix, K.W. C.E. Simpson data were used in this study. 2009. Stability of Fatty Acid Composition of High- and Normal-Oleic Breeding Lines Across Production Regions in the Uniform Peanut Performance Test. American Peanut Research and Education Society - Proceedings. 41: . An abstract.
  • Isleib, T.G., Pattee, H.E., Sanders, T.H., Dean, L.L. and Hendrix, K.W. C.E. Simpson data were used in this study. 2009. Flavor Profiles and Composition of Runner and Virginia Type Cultivars Tested as Part of the Uniform Peanut Performance Test. American Peanut Research and Education Society - Proceedings. 41: . An abstract


Progress 01/01/08 to 12/31/08

Outputs
OUTPUTS: Outputs: Yield tests revealed that three multi-trait breeding lines performed better than the others tested. These lines have resistance to root knot nematode (UL= underline Meloidogyne ULarenaria and ULM. ULjavanica), sclerotinia blight (ULSclerotinia ULminor), tomato spotted wilt virus (TSWV), as well as being high in Oleic/Linoleic acid ratio. These lines were entered into the statewide advanced lines yield test for 2008, but those data are not available at this writing. Quality analyses will be conducted on these lines soon. Other yield tests gave additional confirmation that the new varieties, Tamnut OL06 and Tamrun OL07, outperform other varieties in their important aspects of early maturity and disease resistance. The information from these tests was shared with extension specialists as well as reported to the Texas Peanut Producers Board, the funding agency that made the work possible. Nine hybrid populations were made between a high oil content interspecific breeding line and selected high yielding, disease resistant commercial varieties to develop breeding populations high in oil content. An additional 105 backcross 5 crosses were made from the 630 backcross 4 populations in our effort to construct a tetraploid molecular map and to develop a series of near isogenic lines which would allow us to do prescription breeding of peanut populations. An interspecific hybrid plant with putative resistance to ULSclerotium ULrolfsii was crossed with a high yielding commercial cultivar with multi-traits mentioned above. A MS Thesis project was completed where the effect of distance from the main axis that a peanut seed is set was measured and recorded, with through analyses of the data taken. PARTICIPANTS: One Master of Science candidate worked on this project during 2008 and four undergraduate students worked on the project as well. The collaborators on the project include those listed on the title page: M.D. Burow, M.R. Baring, A.M. Schubert, M.C. Black, and J.L. Starr. TARGET AUDIENCES: The target audiences for our efforts are several fold: The yield data from variety tests is targeted to producers, extension specialists and consultants. The target audience for our more basic type work is fellow research scientests to further the science of peanut breeding, genetics, and germplasm enhancement as well as the taxonomy of the genus Arachis. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.

Impacts
Outcomes: One of the three multi-trait lines with nematode resistance will have seed increase initiated in 2009. The decision of which one will depend upon what the 2008 multi-test data indicate. The selection will provide us with potential to release a new variety to growers in nematode infested areas and could bring several thousand acres of choice peanut production soil back into production. This would have a significant impact on the economy of those counties affected. Potential for Tamnut OL06 and Tamrun OL07 to make a strong contribution to the economy of the peanut growing counties of South and West Texas continues to look very promising. When we finish making all the backcross fives, molecular analyses will tell us which of the hybrid populations to multiply for further evaluation. The impact of a population of near isogenic lines could be significant in future peanut breeding efforts. Resistance to Sclerotium rolfsii has been an elusive trait in cultivated peanut. Developing resistance from a wild species parent would be very important to the peanut industry. The completion of the MS Thesis project provides insight into the formation of seed in peanut and the effects of the distance from the main axis that the seed is set, i.e., the farther from the main axis, the larger the seed will be.

Publications

  • Gomez, S.M., Denwar, N.N., Ramasubramanian, T., Simpson, C.E., Burow, G., Burke, J.J., Pappala, N., and Burow, M.D. 2008. Identification of Peanut Hybrids Using Microsatellite Markers and Horizontal Polyacrylamide Gel. Electrophoresis. Peanut Science 35: 123-129.
  • Burow, Mark D., Simpson, Charles E., Faries, Michael W., Starr, James L., and Paterson, Andrew H. 2009. Molecular biogeographic study of recently described B- and A-genome ULArachis species, also providing new insights into the origins of cultivated peanut. Genome 52: 1-13.
  • Williams, J.E. 2008. Determination of Seed Size in Relationship to the Distance from the Main Axis in ULArachis L. A thesis submitted to the Graduate College of Tarleton State University in partial fulfillment of the degree of Master of Science. Stephenville, TX 76402 pp 1-103.
  • Simpson, C.E., M.D. Burow and M.R. Baring. 2008. Working with a useful Bridge Species to Introgress Genes into ULArachis ULhypogaea L. American Peanut Research and Education Society. Proceedings 40: 12. Abstract.
  • Williams, J.E., C.E. Simpson, D.H. Kattes, and C.L. Higgins. 2008. Determination of Seed Size in Relationship to the Distance from the Main Axis in ULArachis L. American Peanut Research and Education Society. Proceedings 40: 9. Abstract.
  • Denwar, N.N., J. Ayers, C. Simpson, P. Sankara, and M.D. Burow. 2008. Developing Breeding Populations of Peanuts (ULArachis ULhypogaea L.) Through Introduction of Leaf Spot Resistance Genes from Interspecific Hybrids into Adapted Cultivars. 2008. American Peanut Research and Education Society. Proceedings 40: 9. Abstract.
  • Wilson, J.N., M.D. Burow, C.E. Simpson and M.R. Baring. 2008. Evaluating Oil Content of Bolivian Landraces. American Peanut Research and Education Society. Proceedings 40: 9. Abstract.
  • Burow, M.D., J.L. Ayers, A.M. Schubert, C.E. Simpson and M.R. Baring. 2008. Characterization of Early-Maturing Runner Peanut Breeding Lines. American Peanut Research and Education Society. Proceedings 40: 14. Abstract.
  • Baring, M.R. and C.E. Simpson. 2008. Characterization of Three Different Texas Breeding Lines for Disease. American Peanut Research and Education Society. Proceedings 40: 14. Abstract.
  • Burow, Mark D., James L. Starr, Chang-Hwan Park, Charles E. Simpson and Andrew H. Paterson. 2008. Identification of QLTs for Resistance to Early Leafspot (ULCercospora ULarachidicola S. Hori) in an Introgression Population of Peanut (ULArachis ULhypogaea L.). International Plant and Animal Genome Conference XVI. San Diego, CA. Jan. 2008. Poster.
  • Selvaraj, M.G., Simpson, C.E., Pappala, N., Payton, P., Burke, J.J., and Burow, M.D. 2008. Towards an integrated SSR/RFLP map of tetraploid peanut. Advances in ULArachis through Genomics and Biotechnology. ICRISAT, Patancheru, India. November 2008. Abstract.


Progress 01/01/07 to 12/31/07

Outputs
OUTPUTS: Two new cultivars were released and one new germplasm line was released. The Tamnut OL06 cultivar is a large seeded Spanish peanut that will be beneficial to peanut growers in West Texas because it is large enough to meet the industry needs in place of runner peanuts and it is two to four weeks earlier maturing than runner cultivars presently grown. The cultivar is high O/L and thus more desirable to peanut manufacturers. The second cultivar is Tamrun OL07, a runner cultivar that is high O/L as well as highly resistant to sclerotinia blight and highly tolerant to tomato spotted wilt virus (TSWV). This cultivar will be useful to growers in both South and West Texas because of its high yield and disease resistance. The germplasm line, TxAG-8, will be useful to peanut breeders in providing a marker plant in field plantings of screening nurseries and breeding plots of identification of changes from one line to another. Seed of the cultivars has been increased by the Foundation Seed Service of Texas A&M University and will be available in limited supply for commercial production in 2008. Forty two interspecific crosses were attempted in this reporting period, represented by more than 3,000 pollinations. Most of these crosses were attempts to study relationships between different species of wild Arachis, but some of the crosses had dual objectives in working on introgression of genes into cultivated peanut. Other crosses were made in attempts to develop pathways of introgression for introduction of specific genes into the cultigen. Colchicine treatment of several interspecific hybrids resulted in recovery of at least one amphiploid plant, and several more treated plants are being evaluated further for possible chromosome doubling. A total of 102 backcross four progenies were backcrossed to the recurrent parent for a fifth time in our ongoing effort to develop a backcross 5 population in our plan to elucidate a molecular genetic map and establish a population of near-isogenic-lines that each differ in a small portion of wild Arachis chromosome that contains a genetic character that can be identified by flanking molecular markers. This population will then be useful in prescription breeding of the cultivated peanut. A germplasm collection expedition to Paraguay resulted in the introduction of germplasm of one new species to the USDA collection of Arachis as well as seed and plants of five other species which had previously been introduced to the collection. PARTICIPANTS: The PI and all of the collaborators listed on the project contributed to this effort. Funding was received from the Texas Peanut Producers Board, the National Peanut Producers Board, The Peanut Foundation, and the Peanut CRSP TARGET AUDIENCES: Target audiences include peanut farmers, other peanut breeders, other peanut research personnel, peanut extension specialists, and peanut product manufacturing companies as well as the general public. PROJECT MODIFICATIONS: None

Impacts
Of the forty two interspecific crosses attempted, the successful crosses helped us understand the relationships between different species of wild Arachis, as well as move forward on transfer of genes to the cultigen. Other crosses for developing pathways of introgression for introduction of specific genes into the cultigen will require significant more time to ascertain our success. Colchicine development of one amphiploid plant, will be useful in the introgression effort and the several more treated plants that are being evaluated further have potential for aiding in the introgression work. The backcross four progenies backcrossed to the recurrent parent for a fifth time will help us in our plan to expand the molecular genetic map and establish a population of near-isogenic-lines that will be useful in prescription breeding of the cultivated peanut.

Publications

  • Krapovickas, A. and W.C. Gregory. 2007. Taxonomy of the genus Arachis (Leguminosae). Translated by D.E. Williams and C.E. Simpson. Bonplandia 16 (supl.): 1-205.
  • Lopez, Y., M.D. Burow, J.L. Ayers, M.R. Baring, and C.E. Simpson. 2007. Registration of 'TxAG-8' peanut germplasm line. Journal of Plant Registrations 1#2: 150.
  • Baring, M.R., Y. Lopez, C.E. Simpson, J.M. Cason, J. Ayers, and M.D. Burow. 2006. Registration of 'Tamnut OL06' Peanut. Crop Science 46:2720-2721.
  • Baring, M.R., C.E. Simpson, M.D. Burow, M.C. Black, J.M. Cason, J. Ayers, Y. Lopez, and H.A. Melouk. 2006. Registration of 'Tamrun OL07' Peanut. Crop Science 46:2721-2722.


Progress 01/01/06 to 12/31/06

Outputs
We were successful in making numerous crosses involving wild species, cultivated materials, and between wild and cultivated. Most notable of these crosses were crosses involving Arachis magna (and affn. magna) X A. Gregoryi. We were also successful in making crosses between A. stenosperma and A. linearifolia and then crossing that hybrid with both A. batizocoi and A. magna. This latter hybrid is to be chromosome doubled to begin the introgression of resistance to Sclerotium rolfsii (southern blight) into the cultigen, Arachis hypogaea. We were successful in getting eleven new species descriptions completed and published in this last reporting period. These descriptions will be of significant value to those researchers in to world who are interested in working with the wild Arachis in order to improve the cultivated peanut.The data we gathered in seven yield and/or disease screening tests aided in the selection of more than 25 lines for more advanced testing for yield and sclerotinia blight resistance. We identified seven lines from the four 20-entry, multiple location nematode tests which should be further tested and we planted those in the three 2006 tests, at three locations. We also planted an additional 20-entry test of 17 new lines. We provided yield data and disease ratings which helped identify the best of several lines to be submitted for release as the new cultivar, Tamnut OL06. The line Tx034342 was approved for release during this evaluation period. We provided yield data and disease ratings which helped identify the best of several lines to be submitted for release as the new cultivar, Tamrun OL07.

Impacts
The new large seeded Spanish cultivar, Tamnut OL06, could become a highly demanded product because of its desirable seed size and shape and its flavor. The new runner cultivar, Tamrun OL07 could save West and South Texas several millions of dollars because of its disease resistance.

Publications

  • Simpson, C.E., Baring, M.R., Schubert, A.M., Black, M.C., Melouk, H.A., and Lopez, Y. 2006. Registration of Tamrun OL02 peanut. Crop Sci. 46: 1813-1814.
  • Favero, A.P., Simpson, C.E., Valls, J.F.M., and Vello, N.A.. 2006. Study of the evolution of cultivated peanut through crossability studies among Arachis ipaensis, A. duranensis, and A. hypogaea. Crop Science. 46: 1546-1552.
  • Valls, J.F.M. and Simpson, C.E. 2005. Arachis porphyrocalyx Valls and C.E. Simpson sp. nov. pg. 36-38. IN: Valls, J.F.M. and C.E. Simpson. 2005. New species of Arachis from Brazil, Paraguay, and Bolivia. Bonplandia 14:1&2. 35-64.
  • Valls, J.F.M., Krapovickas, A., and Simpson, C.E. 2005. Arachis submarginata Valls, Krapov. and C.E. Simpson sp. nov. pg. 38-41. IN: Valls, J.F.M. and C.E. Simpson. 2005. New species of Arachis from Brazil, Paraguay, and Bolivia. Bonplandia 14:1&2. 35-64.
  • Valls, J.F.M. and Simpson, C.E. 2005. Arachis interrupta Valls and C.E. Simpson sp. nov. pg. 45-47. IN: Valls, J.F.M. and C.E. Simpson. 2005. New species of Arachis from Brazil, Paraguay, and Bolivia. Bonplandia 14:1&2. 35-64.
  • Krapovickas, A., Valls, J.F.M., and Simpson, C.E. 2005. Arachis Schininii Krapov., Valls, and C.E. Simpson sp. nov. pg. 54-56. IN: Valls, J.F.M. and C.E. Simpson. 2005. New species of Arachis from Brazil, Paraguay, and Bolivia. Bonplandia 14:1&2. 35-64.
  • Valls, J.F.M. and Simpson, C.E. 2005. New species of Arachis from Brazil, Paraguay, and Bolivia. Bonplandia 14:1&2:35-64.


Progress 01/01/05 to 12/31/05

Outputs
Improving peanut cultivars through germplasm enhancement continues to be our primary project objective. In recent years we have concentrated more on developing multiple traits in each cultivar because we have developed individual cultivars with resistance to several disease and nematode species, and with improved edible quality traits. In this past reporting period we have evaluated 40 interspecific hybrids produced previously. These data are being used to determine which interspecific hybrids should be chromosome number doubled in anticipation of attempting introgression crosses with Arachis hypogaea, the cultigen. We also produced an additional eight interspecific hybrids in attempts to identify new species which have the B genome of Arachis. A plant exploration trip to Brazil allowed us to locate new populations of old species and to find a population of a new species. Laws do not allow the export of any germplasm material from Brazil at the present time, but it is our desire to preserve materials in the Brazilian Arachis collection with the possibility of obtaining these materials for research use in the future. We tested more than 300 progenies for O/L ratio, and we tested these and an additional 400 for nematode resistance. We yield tested eleven lines from the previous backcross cycle that were winter increased in Puerto Rico in 2004-05. These lines were placed at four locations for evaluation. Two of the lines produced yields equal to check cultivars, but none were better. This past year was the third year of testing some large seeded Spanish breeding lines that were developed in attempts to provide a cultivar for West Texas that matures early and has sufficent seed size and yield to be used by the industry in place of some runner peanuts currently grown but because of not being mature at the end of the growing season lack quality attributes that are needed. We anticipate the release of one of these lines as a cultivar within the next few months. Also, we yield tested three runner lines for a third year, as well as placing them into the UPPT for testing at sites all over the peanut growing belt of the USA. At present we are preparing the documentation to release one of these lines as a new cultivar which will posses a high level of tomato spotted wilt resistance/tolerance, a high level of sclerotinia resistance, and also contain the high O/L trait.

Impacts
The large seeded Spanish line could save West Texas peanut farmers as much as $10 million per year in reduced cost of irrigation. The release of the new multiple disease resistant runner line could provide as much as $7 million annually for South Texas peanut farmers by saving in crop loss and/or chemicals not needed.

Publications

  • Kiniry, J.R., C.E. Simpson, A.M. Schubert, and J.D. Reed. 2005. Peanut leaf area index, light interception, radiation use efficiency, and harvest index at three sites in Texas. Field Crops Research 91:297-306.
  • Ferguson, M.E., A. Jarvis, H.T. Stalker, D. Williams, Luigi Guarino, J.F.M. Valls, R.N. Pittman, C.E. Simpson, and P. Bramel. 2005 Biogeography of Wild Arachis (Leguminosae): Distribution and Environmental Characterization. Biodiversity and Conservation 14 (7): 1777-1798.
  • Jarvas, A., M.E. Ferguson, D.E. Williams, L. Guarino, P.G. Jones, H.T. Stalker, J.F.M. Valls, R.N. Pittman C.E. Simpson, and P. Bramel. 2003. Biogeography of Wild Arachis: Assessing Conservation Status and Setting Future Priorities. Crop Science 43:1100-1108.
  • Valls, J.F.M. and C.E. Simpson. 2005. Arachis porphyricalix Valls & C.E. Simpson nov. sp. (IN Valls, J.F.M. and C.E. Simpson 2005. New species of Arachis L (Leguminosae) from Brazil, Paraguay, and Bolivia. Bonplandia 14:35-64). Bonplandia 14:36-37.
  • Valls, J.F.M., A. Krapovickas, and C.E. Simpson. 2005. Arachis submarginata Valls, Kropov. & C.E. Simpson nov. sp. (IN Valls, J.F.M. and C.E. Simpson 2005. New species of Arachis L (Leguminosae) from Brazil, Paraguay, and Bolivia. Bonplandia 14:35-64). Bonplandia 14:37-38.
  • Valls, J.F.M. and C.E. Simpson. 2005. Arachis Pflugeae C.E. Simpson, Krapov. & Valls. nov. sp. (IN Valls, J.F.M. and C.E. Simpson 2005. New species of Arachis L (Leguminosae) from Brazil, Paraguay, and Bolivia. Bonplandia 14:35-64). Bonplandia 14:39-41.
  • Krapovickas A., J.F.M. Valls and C.E. Simpson. 2005. Arachis Hassleri Krapov. Valls & C.E. Simpson nov. sp. (IN Valls, J.F.M. and C.E. Simpson 2005. New species of Arachis L (Leguminosae) from Brazil, Paraguay, and Bolivia. Bonplandia 14:35-64). Bonplandia 14:41-42.
  • Valls, J.F.M. and C.E. Simpson. 2005. Arachis interrupta Valls & C.E. Simpson nov. sp. (IN Valls, J.F.M. and C.E. Simpson 2005. New species of Arachis L (Leguminosae) from Brazil, Paraguay, and Bolivia. Bonplandia 14:35-64). Bonplandia 14:42-43.
  • Valls, J.F.M., C.E. Simpson, A. Krapovickas, and R.F.A. Veiga. 2005. Arachis seridoensis Valls, C.E. Simpson, Krapov. & Veiga nov. sp. (IN Valls, J.F.M. and C.E. Simpson 2005. New species of Arachis L (Leguminosae) from Brazil, Paraguay, and Bolivia. Bonplandia 14:35-64). Bonplandia 14:43-44.
  • Valls, J.F.M. A. Krapovickas, and C.E. Simpson. 2005. Arachis nitida Valls, Krapov. & C.E. Simpson nov. sp. (IN Valls, J.F.M. and C.E. Simpson 2005. New species of Arachis L (Leguminosae) from Brazil, Paraguay, and Bolivia. Bonplandia 14:35-64). Bonplandia 14:44-45.
  • Valls, J.F.M., A. Krapovickas, and C.E. Simpson. 2005. Arachis linearifolia Valls, Krapov. & C.E. Simpson nov. sp. (IN Valls, J.F.M. and C.E. Simpson 2005. New species of Arachis L (Leguminosae) from Brazil, Paraguay, and Bolivia. Bonplandia 14:35-64). Bonplandia 14:46-47.
  • Krapovickas, A., J.F.M.Valls, and C.E. Simpson. 2005. Arachis Schininii Valls & C.E. Simpson nov. sp. (IN Valls, J.F.M. and C.E. Simpson 2005. New species of Arachis L (Leguminosae) from Brazil, Paraguay, and Bolivia. Bonplandia 14:35-64). Bonplandia 14:47-48.
  • Simpson, C.E., D.E. Williams, J.F.M. Valls, and I.G. Vargas. 2005. Arachis Krapovickasii C.E. Simpson, D.E. Williams, Valls, & I.G. Vargas nov. sp. (IN Valls, J.F.M. and C.E. Simpson 2005. New species of Arachis L (Leguminosae) from Brazil, Paraguay, and Bolivia. Bonplandia 14:35-64). Bonplandia 14:52-53.
  • Simpson, C.E. A. Krapovickas, and J.F.M. Valls. 2005. Arachis Gregoryi C.E. Simpson, Krapov. & Valls nov. sp. (IN Valls, J.F.M. and C.E. Simpson 2005. New species of Arachis L (Leguminosae) from Brazil, Paraguay, and Bolivia. Bonplandia 14:35-64). Bonplandia 14:49-51.


Progress 01/01/04 to 12/31/04

Outputs
Developing cultivars with multiple genetic improvements continues to be a major objective of this project. Our goal is to enhance germplasm resources, especially from the wild Arachis species, and develop germplasm lines that can be utilized by peanut breeders to develop new and improved peanut cultivars. Pest resistance is of utmost importance, but other restraints are equally important; such as; early maturity, improved flavor, high O/L ratio, higher oil content, lower oil content, lower sugar content, etc. A total of 40 interspecific hybrid combinations were accomplished between A and B genome Arachis accessions, most of which were recently introduced into the USA. These hybrids are the first step in determining relationships between various species, in preparation for developing introgression pathways to transfer traits from wild species to the cultigen, A. hypogaea. The 3rd and/or 4th backcrosses were completed with introgression materials in which we are incorporating tomato spotted wilt resistance and sclerotinia resistance into nematode resistant lines which contain the high O/L genes. The BC1 of the mapping population continues to be maintained and evaluated, as does half of the BC4 from the same population. DNA analyses have been done to determine which parents to use for the 5th backcross to develop NILs (near isogenic lines). These NILs will be essential to future breeding efforts which will be done by prescription. Seeds are being increased in Puerto Rico this winter of several large seeded Spanish lines with high O/L, for testing in 2005. Other nematode resistant lines have been increased for testing and evaluation in 2005. Early maturity genes in A. praecox need to be introgressed into A. hypogaea. Therefore, efforts continued on studying hybrids between Arachis praecox and A and B genome species. Success was achieved in doubling the chromosome number of B genome, A. batizocoi X A. praecox, but, to date, none of the hybrids of A genome species which were crossed with A. praecox have been chromosome doubled. The mystery of the two missing chromosomes of A. praecox continues to be studied. The hypotheses is that most of the genes on the two missing chromosomes were incorporated into the remaining chromosomal complement by translocation, or other means.

Impacts
NemaTAM cultivar could help some Central Texas peanut farmers to survive. The high O/L cultivars Tamrun OL 01 and Tamrun OL 02 could add as much as $25 million to Texas peanut farmer income in the 2005 crop season.

Publications

  • Simpson, C.E. 2004. Diversity in Section Arachis and its potential for peanut breeding. 200 word abstract IN: IV Latin-American meeting of Arachis specialists. May 11-14, 2004. CENARGEN/EMBRAPA. Brasilia, Brazil.
  • Favero, Alessandra Pereira. 2004. Crossability among wild species of Arachis for introgression of disease resistance genes into cultivated groundnut. PhD dissertation submitted to the University of Sao Paulo, Piracicaba, Brazil. January 2004. 165 pp.
  • Burow, M.D., Lopez, Y, Ayers, J., Simpson, C.E., Schubert, A.M., Baring, M.R., Dashiell, K., and Melouk, H.A. 2004. Breeding for Early-Maturing Peanut. Abstract. Am. Peanut Res. & Educ. Soc. Proc. p. 33. http://www.apres.okstate.edu/Vol 36 Proc 10-5-04.pdf.
  • Baring, M.R., Simpson, C.E., Melouk, H.A., and Black, M.C. 2004. Comparison of three techniques for selection of multiple disease resistant peanut. Abstract. Am. Peanut Res. & Educ. Soc. Proc. p. 34. http://www.apres.okstate.edu/Vol 36 Proc 10-5-04.pdf.
  • Sankara, P., Ndoye, O., Ilboudo, D., Burow, M., Smith, O.D., and Simpson, C.E. 2004. Performance of Senegalese seed-dormant peanut lines in Burkina Faso. Abstract. Am. Peanut Res. & Educ. Soc. Proc. p. 36. http://www.apres.okstate.edu/Vol 36 Proc 10-5-04.pdf.
  • Sankara, P., Ndoye, O., Zagre, B.M., Burow, M., Smith, O.D., Simpson, C.E. 2004. Selection for resistance to early leaf spot in peanut lines derived from crosses between West African and U.S. germplasm. Abstract. Am. Peanut Res. & Educ. Soc. Proc. p. 37. http://www.apres.okstate.edu/Vol 36 Proc 10-5-04.pdf.
  • Starr, J.L., Morgan, E.R., and Simpson, C.E. 2002. Management of the peanut root-knot nematode, Meloidogyne arenaria, with host resistance. Plant Health Progress Nov. 2002: 5pp.


Progress 01/01/03 to 12/31/03

Outputs
Peanut cultivars with multiple genetic improvements continues to be primary goal of this project. We have released NemaTAM, OLin, Tamrun OL 01, and Tamrun OL 02 with multiple traits, but we continue to strive to improve on these latest releases. We were successful in completing the third backcross cycle to incorporate high O/L and sclerotinia resistance into NemaTAM. We completed a second years testing on Spanish BC4 lines derived from the OLin cultivar which was released from the backcross one progeny. The BC4 lines appear to be in the same yield grouping as Tamspan 90, which is a significant improvement over the OLin. Tamrun OL 01 has performed very well for peanut growers in South Texas, but the Tamrun OL 02 should replace the Tamrun OL 01 plantings when seed are available because Tamrun OL 02 is significantly lower in sugar content and a little higher yielding than Tamrun OL 01 and has a much more desirable seed size than does Tamrun OL 01. Other new materials have shown a significantly higher resistance to sclerotinia than Tamrun 96, Tamrun OL 01, and Tamrun OL 02. These lines also have the high O/L trait and a few of them also contain the RK nematode resistance genes. Further evaluation of the BC4 lines in the genome mapping population indicate lines can be selected for the BC5 in our effort to develop a series of near isogenic lines (NIL) to use in prescription breeding. New crosses and progeny evaluations indicate that some of the accessions collected in Paraguay in 2002 are closely associated (in a taxonomic sense) to Arachis duranensis, whereas two of the accessions are more closely associated with A. batizocoi. We still have not been successful in identifying a pathway for introgressing early maturity genes into cultivated peanut from the 18 chromosome, A. praecox. DNA analyses of A. praecox and other parents have not been fruitful to date.

Impacts
NemaTAM cultivar could help some Central Texas peanut farmers to survive. The high O/L cultivars OLin, Tamrun OL 01 and Tamrun OL 02 could add as much as $35 million to Texas peanut farmer income in the 2004 crop season.

Publications

  • Lopez, Y., Nadaf, H.L., Smith, O.D., Simpson, C.E., and Fritz, A.K. 2002. Expressed variants of Delta12-fatty acid desaturase for the high oleate trait in spanish market-type peanut lines. Molecular Breeding 9:183-190.
  • Jarvis, A., Williams, D.E., Ferguson, M., Stalker, H.T., Valls, J.F.M., Bramel, P., Pittman, R.N., and Simpson, C.E. 2003. GIS Evaluation of the Wild Arachis Germplasm collections. Crop Science. 43:1100-1108.
  • Simpson, C.E., Starr, J.L., Church, G.T., Burow, M.D., and Paterson, A.H. 2003. Registration of NemaTAM Runner Peanut. Crop Science 43:1561.
  • Simpson, C.E., Baring, M.R., Schubert, A.M., Melouk, H.A., Lopez, Y., and Kirby, J.S. 2003. Registration of OLin Spanish Peanut. Crop Science 43:1880.
  • Simpson, C.E., Baring, M.R., Schubert, A.M. Melouk, H.A. Lopez, Y., Black, M.C., and Kirby, J.S. 2003. Registration of Tamrun OL01 Runner Peanut. Crop Science 43:2298.


Progress 01/01/02 to 12/31/02

Outputs
Overall Objective: Enhance Arachis hypogaea through hybridization and by introgressing genes from wild Arachis species. NemaTAM, the world's second root-knot nematode [Meloidogyne arenaria (Neal) Chitwood] resistant peanut cultivar was released in 2002. Resistance was introgressed from Arachis cardenasii. NemaTAM is 32% higher yielding than the first release, COAN. Limited seed will be available for the 2003 crop planting. Also released were three cultivars with a high ratio of oleic acid as compaired to linoleic acid. The OLin cultivar is a Spanish type with resistance characteristics similar to Tamspan 90, but yields about 10% less than Tamspan 90. The O/L ratio of OLin is 14 to 25, depending upon location of growth. The second O/L cultivar released was Tamrun OL01, a large seeded runner peanut. TROL01 yields about 10 to 12% above Tamrun 96 and has some of the same disease resistant characters of Tamrun 96 such as tolerance to tomato spotted wilt, southern blight, and sclerotinia blight. A third high O/L runner cultivar was released, Tamrun OL02. Tamrun OL02 has smaller seed than Tamrun OL01 and the sugar content is 13% lower than Tamrun OL01. More than 100 lines from the backcross four of Spanish high O/L lines to Tamspan 90 were increased in the Puerto Rico winter nursery. The seed increase was planted in three replicated tests in Central and West Texas and Oklahoma. We anticipate significant increase in yield and grade over previous backcrosses of these lines. In DNA work the third backcross to transfer nematode resistance into Tamrun 96 using MAS (marker assisted selection) was completed. The fourth backcross was completed in our effort to combine RK nematode resistance with the high O/L genes. In our Genome Project collaboration, the 4th backcross of 98 BC3s was accomplished and material has been collected from 345 BC4F1s and DNA extraction is in progress. The second half of the BC4F1s will be planted soon. Crosses were made with 11 new accessions collected in the Chaco of Paraguay during 2002. These crosses are to help determine genome affinity and species identity. A cross compatibility study between the 1994 Bolivia collection and the wild species A. ipaensis was completed, verifying several new B genome accessions. The wild Arachis backup collection has faired well in the past year, with only minor losses and some gains from the collections in Paraguay. Several accessions were provided to the USDA Curator as either new accessions or replacement materials.

Impacts
The RK nematode resistance transfer from wild to cultivated peanut will have a significant impact on peanut production in the not too distant future. The molecular map from our genome work can make a significant impact on peanut breeding worldwide and the NIL's being developed will play a large role in developing cultivars in the near future.

Publications

  • Simpson, C.E., A. Krapovickas, and J.F.M. Valls. 2001. History of Arachis including Evidence of A. hypogaea L. Progenitors. Peanut Science 28:78-80.
  • Simpson, C.E. 2001. Use of Wild Arachis Species/Introgression of Genes into A. hypogaea L. Peanut Science 28:114-116.
  • Pattee, H.E., T.G. Isleib, D.W. Gorbet, K. Moore, Y. Lopez, M.R. Baring, and C.E. Simpson. 2002. Effect of the high oleic trait on roasted peanut flavor in backcross-derived breeding lines. J. Agric. Food Chem. 50:7362-7370.


Progress 01/01/01 to 12/31/01

Outputs
Objectives: Enhance Arachis hypogaea from wild species germplasm by introgression of desirable genes. COAN, the first peanut variety in the world with resistance to root-knot nematode [Meloidogyne arenaria (Neal) Chitwood], was too low yielding to be commercially acceptable. The gene for resistance was transferred through a pathway developed and published under this project in 1991. The pathway involved a backcrossing program where the complex synthetic amphiploid, TxAG-6 was crossed with Florunner, and then Florunner was used as the recurrent parent. COAN is a progeny from the 5th backcross cycle. Selections from the 7th backcross are 32% higher yield than COAN in three years tests. Seed increase is underway with anticipated release of TP301-1-8 as a high yielding root-knot nematode resistant variety soon. Molecular markers closely associated with the gene for RK nematode resistance are being used in marker assisted selection (MAS) to transfer the nematode resistance gene into lines which have other traits, such as, TSWV resistance and high O/L ratio. Introgression of leafspot resistance and early maturity genes is underway. Two lines have shown potential for good leafspot resistance, but yields have been less than desired. An additional backcross was made and tested. Release of these lines as germplasm may be justified. Seed increase is underway on a high O/L, TSWV resistant runner type breeding line that has a very large seed. A high O/L sclerotinia resistant Spanish type line has also been seed increased. Release of these lines is anticipated early in 2002. An additional high O/L runner line with smaller seed is being increased and we anticipate release of this line within the next 12 months. The pathway for introgression of early maturity has not been completed. The desired genes were found in A. praecox (VSGr-6416), but the species has only 18 chromosomes. Hybrids and subsequent amphiploids have been produced, followed by crosses with A. hypogaea. However, the backcrosses have not been successful to date because of complete sterility of the interspecific hybrid with cultivated peanut lines. Inheritance studies on seed dormancy in erect/bunch type peanut lines have produced two potential new cultivars for semi-arid environments in West Africa. Cross-compatibility studies within and between A and B genome species confirmed several accessions affinity giving more complete information for description of 11 new species of Arachis and identifying new materials for the introgression program.

Impacts
The development of nematode resistance in cultivated peanut could have a significant positive impact on profits for US peanut farmers. An additional impact relates to reduced chemical applications, which have a negative affect on our environment. The first could result in several millions of dollars annually. The second is difficult to measure monetarily. Spanish and runner type peanut lines with high O/L ratio and good disease resistance could have positive multi-million dollar impacts on the US peanut industry. The three new cultivars mentioned in this report could be an additional $30 million per year for Texas peanut growers.

Publications

  • Simpson, C.E. and Starr, J.L. Lasswell, J.L., and Foreman, C.A. 2001. Cover Picture on Crop Science Journal. Crop Science 41.
  • Lavia, G., Fernandez, A., Simpson, C.E., and Seijo, G. 2001. Cytologia: IN PRESS.
  • Church, G.T., Simpson, C.E., Burow, M.D., and Starr, J.L. 2001. Identification of RFLP loci flanking a nematode resistance locus in peanut. Phytopathology 91:S17.


Progress 01/01/00 to 12/31/00

Outputs
Objectives: Enhance Arachis hypogaea from wild species germplasm by introgression of desirable genes. 'COAN', the first peanut variety in the world with resistance to root-knot nematode [Meloidogyne arenaria (Neal) Chitwood], yields are 75 to 300% higher than 'Florunner' under various levels of nematode pressure. however, the yield potential does not appear to be sufficient for the variety to be commercially acceptable. The gene for resistance was transferred through a pathway developed and published under this project in 1991. The pathway involved a backcrossing program where the complex synthetic amphiploid, TxAG-6 was crossed with Florunner, and then Florunner was used as the recurrent parent. COAN is a progeny from the 5th backcross cycle. COAN is not immune to the root-knot nematode, however infection rates are less than 1% when susceptible checks are 100% infected and plants are completely dead. Selections from the 7th backcross had 32% higher yield than COAN in two year's tests. Seed increase is underway for one of these lines, with anticipated release as a high yielding root-knot nematode resistant variety within the next 12 mo. Molecular markers closely associated with the gene for RK nematode resistance are being used in marker assisted selection (MAS) to transfer the nematode resistance gene into lines which have other traits, such as, TSWV resistance and high O/L ratio. Introgression of leafspot resistance and early maturity genes is underway. Two lines have shown potential for good leafspot resistance, but yields have been less than desired. An additional backcross is indicated. Release of these lines as germplasm may be justified. Seed increase is underway on a high O/L, TSWV resistant runner type breeding line as well as a high O/L sclerotinia resistant Spanish type line. Release of these lines is anticipated within the next calendar year. The pathway for introgression of early maturity has not been completed. The desired genes were found in A. praecox (VSGr-6416), but the species has only 18 chromosomes. Hybrids and subsequent amphiploids have been produced, followed by crosses with A. hypogaea. However, the backcrosses have not been successful to date because of complete sterility of the interspecific hybrid with cultivated peanut lines. Inheritance studies on seed dormancy in erect/bunch type peanut lines have produced two potential new cultivars for semi-arid environments in West Africa. Cross-compatibility studies within and between 'A' and 'B' genome species confirmed several accession's affinity giving more complete information for description of 11 new species of Arachis and identifying new materials for the introgression program.

Impacts
The development of nematode resistance in cultivated peanut could have a significant positive impact on profits for US peanut farmers. An additional impact relates to reduced chemical applications, which have a negative affect on our environment. The first could result in several millions of dollars annually. The second is difficult to measure monetarily. Spanish and runner type peanut lines with high O/L ratio and good disease resistance could have positive multi-million dollar impacts on the US peanut industry.

Publications

  • Simpson, C.E., Smith, O.D., and Melouk, H.A.. 2000. Registration of Tamrun 98 Peanut. Crop Science 40: 859.
  • Simpson, C.E. and Starr, J.L. 2001. Registration of COAN peanut. Crop Science 41: IN PRESS.
  • Simpson, C.E. 1999. Pre-breeding in Arachis. In session: Pre-breeding aimed at the efficient use of Latin American Genetic Resources. Second Symposium on Genetic Resources for Latin America and the Caribbean (SIRGEALC). CENARGEN/EMBRAPA 25th Anniversary Celebration. 21 - 26 November, 1999. CENARGEN/EMBRAPA, SAIN Parque Rural, Brasilia DF Brazil.
  • Lopez, Y., Smith, O.D., Senseman, S.A., Simpson, C.E., Rooney W.L. 2000. Genetic Factors influencing High Oleic Acid content in Spanish-type Peanut cultivars. American Peanut Research and Education Soc. Proc. Abstract. Vol.32: IN PRESS.
  • Baring, M.R., Black, M.A., and Simpson, C.E. 2000. Identification of US-224 (PI 475871) as the source of resistance to Tomato Spotted Wilt Virus in Tamrun 96. American Peanut Research and Education Soc. Proc. Abstract. Vol.32: IN PRESS.
  • Lopez , Y. 1999. Studies for the high oleate:low linoleate seed trait in Spanish market-type peanuts (Arachis hypogaea L.): Inheritance and a search for molecular polymorphism. A dissertation submitted to the Graduate College, Texas A&M University for the partial fulfillment of the requirements for the PhD. Degree. January 1999. pp. 167 Texas A&M University, College Station, TX 77843.
  • Church, G.T., Simpson ,C.E., Burow, M.D., Paterson, H.A., and Starr, J.L.. 2000. Use of RFLP markers for identification of individuals homozygous for resistance to Meloidogyne arenaria in peanut. Submitted to Nematology 2.
  • Meador, C.B., Lee, T.A., Wells, J.A., Simpson, C.E., and Starr, J.L. 2000. Peanut Susceptibility to an Undescribed Root-knot Nematode. American Peanut Research and Education Soc. Proc. Abstract. Vol.32: IN PRESS.
  • Krapovickas, A., Valls, J.F.M., and Simpson, C.E. 2000. History of Arachis including Evidence of A. hypogaea progenitors. American Peanut Research and Education Soc. Proc. Abstract. Vol.32: IN PRESS.
  • Simpson, C.E. 2000. Use of Wild Arachis/Introgression of Genes from Wild Arachis into A. hypogaea. American Peanut Research and Education Soc. Proc. Abstract. Vol.32: IN PRESS.
  • Simpson, C.E., Baring, M.A., Lopez, Y. Higgins, W.H., Cason, M. 2000. Possible cause of abnormal kernels observed in Peanut Varieties. American Peanut Research and Education Soc. Proc. Abstract. Vol.32: IN PRESS.


Progress 01/01/99 to 12/31/99

Outputs
Objectives: Enhance Arachis hypogaea from wild species germplasm by introgression of desirable genes. 'COAN' was released as the first peanut variety in the world with resistance to root-knot nematode [Meloidogyne arenaria (Neal) Chitwood]. COAN yields are 75 to 300% higher than 'Florunner' under various levels of nematode pressure. The gene for resistance was transferred through a pathway developed and published under this project in 1991. The pathway involved a backcrossing program where the complex synthetic amphiploid, TxAG-6 was crossed with Florunner, and then Florunner was used as the recurrent parent. COAN is a progeny from the 5th backcross cycle. COAN is not immune to the root-knot nematode, however infection rates are less than 1% when susceptible checks are 100% infected and plants are completely dead. Selections from the 7th backcross had 32% higher yield than COAN in 1999 yield tests. Seed increase is underway for two of these lines. Molecular markers have been identified that are closely associated with the gene for resistance and we are using marker assisted selection (MAS) to transfer the nematode resistance gene into 'Tamrun 96'. The nematode resistance gene has also been introduced into a high O/L ratio background. Introgression of leafspot resistance and early maturity genes is underway. Two lines have shown potential for good leafspot resistance, but yields have been less than desired. An additional backcross is indicated. The pathway for introgression of early maturity has not been completed. The desired genes were found in A. praecox (VSGr-6416), but the species has only 18 chromosomes. Hybrids and subsequent amphiploids have been produced, followed by crosses with A. hypogaea. However, the backcrosses have not been successful to date because of complete sterility of the interspecific hybrid with cultivated peanut lines. Inheritance studies on seed dormancy in erect/bunch type peanut lines have produced two potential new cultivars for semi-arid environments in West Africa. Cross-compatibility studies within and between 'A' and 'B' genome species confirmed several accession's affinity, giving more complete information for description of 11 new species of Arachis.

Impacts
The development of nematode resistance in cultivated peanut could have a significant positive impact on profits for peanut farmers in Texas, Georgia, Florida, Alabama, and North Carolina. An additional impact relates to reduced chemical applications, which have a negative affect on our environment. The first could result in several millions of dollars annually. The second is difficult to measure monetarily.

Publications

  • Starr, J.L., Simpson, C.E., and Lee, T.A.,Jr. 1998. Yield of peanut genotypes resistant to root-knot nematodes. Peanut Science 25:119-123.
  • Choi, K., Burow, M.D., Church, G., Burow, G., Paterson, A.H., Simpson, C.E., and Starr, J.L. 1999. Genetics and mechanism of resistance to Meloidogyne arenaria in peanut germplasm. J. Nematol. 31: 283-290.
  • Burow, M.D., Simpson, C.E., Starr, J.L., and Paterson, A.H. 1999. Generation of a molecular marker map of the cultivated peanut, Arachis hypogaea L. Proc. Plant and Animal Genome VII. San Diego, CA. Jan 17-21, 1999.
  • Burow, M.D., Ballester-Valveny, J., Boothe, J.M., Church, G., Gunawan, G., Yuksel, B., Cason, J., Balagtas-Burow, G., Schulze, S., Choi, K., Warr, G., Simpson, C.E., Starr, J.L., and Paterson, A.H. 1999. Use of marker assisted selection in Peanut improvement. Plant and Animal Genome VII, January 1999. San Diego, CA.


Progress 01/01/98 to 12/31/98

Outputs
The new runner variety, Tamrun 98, was released by the Texas Agric. Exp. Stn. This new sclerotinia (Sclerotinia minor) resistant variety out yields Florunner by 20 to 90% under moderate to heavy disease pressure. The variety is similar to Florunner in maturity, seed size, shelling percentage, and plant characteristics. Tamrun 96 has been accepted by growers in several areas of Texas, and has performed well under pressure from tomato spotted wilt virus and southern blight (Sclerotium rolfsii). Nematode resistant progenies from the BC7F2&3 were tested in two locations in 1998. The BC5F4&5 and BC6F2&3 progenies were yield tested in five counties in 1998, and the resistant lines were at least 55% higher yielding under nematode pressure, and one runner line was 10% higher than Florunner with no nematodes present. Three molecular markers have been identified as being associated with one gene for the nematode resistance. The gene came from A. Cardenasii or A. Diogoi. Transfer of nematode resistance to Tamrun 96 has been initiated using DNA marker based selection. We have made the original cross, selected homozygous resistant progenies and are preparing to make the 1st BC. A program was initiated to transfer early maturity from Arachis praecox (2n=18) into cultivated peanut. Progenies resulting from crosses with "A" genome duranensis, stenosperma, and villosa were not totally pollen sterile, as expected, however, no seed were produced. Seed dormancy is being developed in erect types var. vulgaris and var. peruviana. Evaluation of other "B" genome species hybrids, "A" genome species hybrids, and morphological studies contributed to preparation of descriptions of twelve new species.

Impacts
(N/A)

Publications

  • SMITH, O.D., SIMPSON, C.E., BlACK, M A. and BESKER, B.A. 1998. Registration of Tamrun 96 Runner peanut. Crop Science 38:1403.
  • ABDEL-MOMEN, S. M., SIMPSON, C.E., and STARR, J.L. 1998. Resistance of Interspecific Arachis Breeding Lines to Meloidogyne javanica and an undescribed Meloidogyne species. Journal of Nematology. 30(3):341-346.
  • SINGH, A.K., SMARTT, J., SIMPSON, C.E., and RAINA, S.N. 1998. Genetic variation vis-a-vis molecular polymorphism in groundnut, Arachis hypogaea L. Genetic Resources and Crop Evolution 45:119-126.


Progress 01/01/97 to 12/31/97

Outputs
The new runner variety, Tamrun 96, continues to perform about 12% better than Florunner. When tomato spotted wilt is present in high rates, Tamrun 96 has been superior to Florunner by as much as 48%. Tamrun 96 has also shown good tolerance to the disease caused by Sclerotium rolfsii commonly called white mold or southern blight. The seed increase of Tamrun 96 has been accomplished and some seed will be available for the 1998 crop. Tamspan 90 continues to be profitable for peanut growers with high levels of Sclerotinia minor in their soil. The Foundation Seed Service grew a 30+ acre breeder seed increase of the sclerotinia resistant Tx901417 runner line in 1997. Only seed for foundation-seed increase will be available for 1998. Seed for all growers should be available in the 1999 crop season. More shelling, blanching, chemical analyses, and organoleptic data are needed. Nematode resistant progenies from the BC7F2&3 will be ready for yield tests in 1998. The BC5F4&5 and BC6F2&3 progenies were yield tested in three counties in 1996 and 1997, and the resistant lines were at least 55% higher yielding under nematode pressure, and one runner line was 10% higher than Florunner with no nematodes present. Three molecular markers have been identified as being associated with one gene for the nematode resistance. The gene came from A. cardenasii or A. diogoi. Transfer of nematode resistance to Tamrun 96 has been initiated using DNA marker based selection. Program initiated to transfer early maturity from Arachis praecox (2n=18) into cultivated peanut. Seed dormancy is being developed in erect types var. vulgaris and var. peruviana. Evaluation of 10 interspecific hybrids shows additional evidence of other B genome species.

Impacts
(N/A)

Publications

  • Simpson, C.E. and Coffelt, T.A. 1997. Taxonomy of the Genus Arachis. Compendium of Peanut Diseases. Second Edition. APS Press. pp. 94. ED. N. Kokalis-Burelle et al. American Phytopathological Society. St. Paul, MN 55121. USA.
  • Coffelt, T.A. and Simpson, C.E. 1997. Origin of the Peanut. Compendium of Plant Diseases. Second Edition. APS Press. pp.94. ED. N. Kokalis-Burelle et al. American Phytopathological Society. St. Paul, MN 55121. USA.


Progress 01/01/96 to 12/30/96

Outputs
The new runner variety, Tamrun 96, was released. Tamrun 96 has given a consistent yield increase over Florunner in excess of 12%. When tomato spotted wilt is present in high rates, Tamrun 96 has been superior to Florunner by as much as 48%. The new variety has also shown good tolerance to the disease caused by Sclerotium rolfsii commonly called white mold or southern blight. Breeder seed increase of Tamrun 96 was accomplished and more than 100 thousand pounds of foundation seed will be available for the 1997 crop. Tamspan 90 continues to be profitable for peanut growers with high levls of Sclerotinia minor in their soil. Five runner breeding lines with Sclerotinia resistance were winter seed increased in Puerto Rico and then increased again at the Yoakum TAES Research Station in 1996. Yield tests indicate that the line "1417" will probably be our best choice as a variety. Shelling, blanching, chemical analyses, and organoleptic data are still needed. Nematode resistant progenies from the BC7F2 will be ready for yield tests in 1997. The BC5 progenies were yield tested in three counties in 1996. The resistant lines were at least 55% higher yielding under nematode pressure, and one runner line was 10% higher than Florunner with no nematodes present. Three molecular markers were identified as being associated with one gene for the nematode resistance. The gene came from A. cardenasii or A. diogoi. Evaluation of 19 interspecific hybrids show evidence of additional B genome species.

Impacts
(N/A)

Publications

  • OUEDRAGO, M., SMITH, O.D., SIMPSON, C. E., and SMITH, D.H. 1994. Early and late CLeafspot and Agronomic performance of nineteen interspecific drived peanut nlines. Peanut Science 21:99-104. pSTARR, J.
  • L., SIMPSON, C. E., and LEE, T.A. 1995. Resistance to Meloidogyne arenaria in advanced breeding lines of peanut. Peanut Science 22:59-61.
  • GOLDMAN, J.J., SMITH, O. D., SIMPSON, C.E. and MELOUK, H.A. 1995. Progress in breeding sclerotinia blight-resistant runner-type peanut. Peanut Science 22:109-113.
  • STARR, J.L., SHIM, M.-Y., LEE, T. A., Jr. and SIMPSON, C.E. 1996. Additive effects of Meloidogyne arenaria and Sclerotium rolfsii on peanut. Journal of Nematology 28:99-106.
  • STALKER, H. and SIMPSON, C. 1995. Germplasm resources in Arachis. pp. 14-53, Ch.2. IN: Advances in Peanut Science, H.E. Pattee and H.T. Stalker, eds. Amer. Peanut Res. and Educ. Soc., Inc. Stillwater, OK 74078. pp 614.
  • SMITH, O.D. and SIMPSON, C.E. 1995. Selection of peanut cultivars. Chap. 3 pp. 19-22. IN: Melouk, H.A. and Shokes, F.M. (eds.) Peanut Health Management APS PRESS. Amer. Phytopath. Soc. St. Paul, MN.
  • KRAPOVICKAS, A., GREGORY, W., VALLS, J., and SIMPSON, C. 1994. A. Giacomettii Krapov., W. Gregory, Valls, and C. Simpson. nov. sp. p71-72. IN: Taxon. del genero Arachis. Krapovickas, A. and Gregory, W. Bonplandia 8:1-186.


Progress 01/01/95 to 12/30/95

Outputs
The Tamspan 90 variety continues to perform well for growers who have fields infested with sclerotinia blight (Sclerotinia minor). Farmer income in Texas and Oklahoma was increased an estimated $12 million in 1995 by Tamspan 90. The transfer of the sclerotinia resistance of Tamspan 90 to runner types is complete. We are now identifying lines for release through yield and quality evaluations. Winter increase of seed in Puerto Rico will advance our position to have a variety in the growers hands within three years. Fifty lines were selected for yield tests in 1995 from 235 selections from the 1994 sclerotinia screening nursery. Seed were increased in Puerto Rico in winter of '94-'95 and again in 1995 at Yoakum of Tx896100, a breeding line with some tolerance to tomato spotted wilt virus and sclerotinia, but also with more than a 10% increase in yield without disease. Application for release is being prepared. Two lines resistant to leafspot were selected from 180 lines tested at Yoakum in 1994. This brings the total number of lines tested to more than 2,800, and approximately 185 resistant selections.

Impacts
(N/A)

Publications


    Progress 01/01/94 to 12/30/94

    Outputs
    The major objective of this project is to develop new and improved peanut cultivars by utilizing germplasm, both enhanced and original, from the extensive collection of both cultivated and wild species of Arachis materials which are available. The `Tamspan 90' variety continues to gain in popularity among farmers because of its excellent disease resistance and strong pegs and peg attachments. A conservative estimate of its increase in value to the peanut farmers of the southwest production area for the 1994 crop is $11 million. In our effort to transfer sclerotinia resistance from Tamspan 90 to runner types we have determined that two late season ratings on a 1 to 10 scale is just as effective in making selections as the more time consuming method of plant by plant inspection (PPI) five to eight times after the disease becomes active. This will save a lot of time and expense in conducting screening for sclerotinia resistance. We selected 17 lines with desirable plant and pod type from three yield tests under sclerotinia disease pressure for further testing in 1994. From 1,375 lines in the sclerotinia screening plots, 325 were selected for additional testing under sclerotinia disease pressure in 1994. Of 113 cultivated germplasm lines screened for leafspot resistance at Yoakum, only four were selected as being resistant enough to warrant further testing.

    Impacts
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    Publications


      Progress 01/01/93 to 12/30/93

      Outputs
      The major objective of this project is to develop new and improved peanut cultivars by utilizing germplasm, both enhanced and raw from the extensive collection both cultivated and wild species of Arachis materials which are available. The `Tamspan 90' variety continues to gain in popularity among farmers because of its excellent disease resistance and strong pegs and peg attachments. It is significant that this variety can withstand considerable abuse from weather and sub-par management. In our effort to transfer sclerotinia resistance from Tamspan 90 to runner types, five runner lines were selected from the 1989, 1990 and 1991 sclerotinia resistance tests for more advanced testing and for greenhouse seed increase to develop a disease free seed source for more widespread testing. Yields of lines from two additional yield tests were somewhat disappointing, but did give us an indication of which families we should concentrate our selection work on in 1993. From 1,233 lines in the sclerotinia screening plots, 27 were selected for yield testing and 340 were selected for additional testing under sclerotinia disease pressure. Of 250 cultivated germplasm lines screened for leafspot resistance at Yoakum, 48 were selected as being resistant enough to warrant further testing. A dryland Florunner seeding rate study again showed us that a seeding rate of 30 to 35 pounds per acre will produce just as much yield as higher seeding rates.

      Impacts
      (N/A)

      Publications


        Progress 01/01/92 to 12/30/92

        Outputs
        The sclerotinia resistant `Tamspan 90' peanut variety continues to increase in popularity. Farmer yields were excellent in 1992, and demand for seed will be higher than the supply in 1993. The transfer of the sclerotinia resistance from Tamspan 90 to runner types made good progress, with 187 selections for retesting made from 1,400 lines. Sixty-one of these lines have been tested three times and 33 of them were yield tested in 1992. Results are not complete, but preliminary indications are encouraging. Biocontrol of sclerotinia in peanut shows good promise, with some native and commercial biocontrol-agents working well under laboratory conditions. Field screening indicates extensive rate-of-application studies will be needed. Addition of artificial substrates may give a measure of control of sclerotinia blight, but more research will be needed. Forty-eight selections were made from 250 new germplasm lines tested at Yoakum for leafspot resistance. This brings the total to 2,750 lines tested, with 186 lines selected with sufficient leafspot and/or rust resistance for retesting. Second year data on dryland `Florunner' seeding rate studies still indicate seeding rates above 44.8 Kg/per hectare (40 lbs./acre) are not cost effective. Seed multiplication and preliminary evaluation of more than 200 new germplasm lines were successful. USDA Descriptors were applied to 100 Arachis hypogaea germplasm lines and seed multiplied for preservation at the SRPIS, Griffin, GA. The data will be made available through GRIN.

        Impacts
        (N/A)

        Publications


          Progress 01/01/91 to 12/30/91

          Outputs
          Adequate seed of `Tamspan 90' peanut should be available to any grower who wantsseed in 1992. Further testing of Tamspan 90 under heavy sclerotinia pressure resulted in a 10% infection for Tamspan 90, 52% for `Florunner' and 71% for `Langley'. In the program to transfer sclerotinia resistance from Tamspan 90 into runner breeding lines, screening of almost 2000 plant rows from various crosses and germplasm lines resulted in selection of 374 lines with sufficient sclerotinia resistance to warrant additional testing. Some of the selected lines had desirable agronomic characters with good runner pod type. Early maturity was noted in several lines. Additional lines were generation advanced for testing in 1992 and new crosses were accomplished to develop populations for future testing. Chemical control of sclerotinia was significantly enhanced by following an application schedule based on the threshold soil temperature of 28(degree)C. Preliminary screening of 250 germplasm lines for leafspot resistance resulted in selection of 14 lines for further testing. Dryland seeding rate studies on Floruner resulted in no significant differences in yield or grade between 11.2, 22.4, 33.6, 44.8, and 67.2 Kg. of seed per ha. (10, 20, 30, 40, and 60 lbs. of seed/acre). Analyses and interpretation of data from 14 yield tests is not complete. Seed multiplication on 283 germplasm lines was accomplished and the seed transferred to the Peanut Curator at the SRPIS, Griffin, GA.

          Impacts
          (N/A)

          Publications


            Progress 01/01/90 to 12/30/90

            Outputs
            TX-798736-1 was released as 'Tamspan 90', a new disease resistant Spanish peanutcultivar. Tamspan 90 averaged 10% higher yield than Starr in 3 years of multi-location testing. This new cultivar has a good level of resistance to Sclerotinia blight, caused by Sclerotinia minor and to Pythium spp. pod rotting organisms. Certified seed should be readily available to peanut growers in 1991. Almost 600 lines of F(4) and F(5) to F(8) progenies were screened with >150 being selected as resistant to Sclerotinia blight. None of the 300+ introduced germplasm lines tested exhibited sufficient Sclerotinia blight resistance to justify further evaluation. Various germplasm lines and interspecific hybrid progenies were screened for leafspot resistance. Some lines were higher yielding and had better resistance to early leafspot than 'Southern Runner'. None of the higher yielding interspecific derived lines were significantly better than check entries for both early and late leafspot. Tamrun 88 did quite well in many farmer's plantings in 1990. Ample seed should be available to growers for planting in 1991. Tests on Tamrun 88 still show a good advantage over Florunner in gross value. Seed multiplication was successful of 325 germplasm introductions. These seed have been forwarded to the SRPIS at Griffin, GA, for preservation and distribution.

            Impacts
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            Publications


              Progress 01/01/89 to 12/30/89

              Outputs
              Seed of Tamrun 88 will be adequately available to peanut farmers in 1990. Yieldsand grades continue to show a 3 to 4% advantage of Tamrun 88 over Florunner. The second breeder seed increase of the Sclerotinia resistant Tx 798736-1 spanish breeding line was accomplished. Application for release is high priority. Data indicate at least a 10% yield advantage for Tx 798736-1 over existing spanish vars. without Sclerotinia infection; the difference is greater with Sclerotinia infection. Twelve lines were selected for further testing for Sclerotinia resistance from 451 germplasm and breeding lines tested. Approx. 270 individual plants were selected for further testing for Sclerotinia resistance from a segregating nursery of F(2), F(3), and F(n) generation materials from adapted var. X resistant crosses. Results show, without question, that knowing mean soil temperature can play a significant role in predicting outbreaks of Sclerotinia blight on peanut. Apparently there is little or no difference in predictability between mean temperatures recorded at 5 or 13cm depth. An additional 248 South American germplasm lines were screened for leafspot, rust, and pod rot resistance. Selections were made for further testing. Twelve lines from the leafspot introgression program were re-tested for yield and grade characters without disease pressure -- results are pending. Seed were multiplied on 564 germplasm lines from South America, Africa, India, and China.

              Impacts
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              Publications


                Progress 01/01/88 to 12/30/88

                Outputs
                Tamrun 88 (Tx-771174) was approved for release as a high yielding, high grading runner peanut cultivar. A limited quantity of seed should be available in 1989. Seed were increased on a Sclerotinia resistant spanish breeding line (Tx-798736-1) by winter increase in Puerto Rico, then summer increase in Texas. Almost 1,300 Kg of farmer stock breeder seed are now on hand. This line is to be proposed for release in 1989. Preliminary results indicate no varietal differences in yield between chemical control of Sclerotinia vs. no control on 12 peanut vars. 564 peanut germplasm and breeding lines were screened for Sclerotinia resistance. 25 lines were selected for further testing. In vitro growth of S. minor isolates from 3 peanut producing areas of Texas was temperature X isolate X substrate dependent. Maximum radial growth occurred at 24-26 C on PDA and 18-22 C on corn meal and Czapec Dox agars. The number of sclerotia was highly correlated with radial growth, but total weight of sclerotia did not correlate with growth rate. Soil populations of S. minor sclerotia in peanut soil varied throughout the growing season and size of sclerotia varied with chemical treatment. Two biocontrol agents (Trichoderma sp., Gliocladium sp.) reduced the number of viable sclerotia in peanut soil and the antagonists were isolated from most of the sclerotia taken in soil assays. 250 germplasm lines were screened for leafspot and rust resistance. Approx. 45 lines were selected for further evaluation.

                Impacts
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                Publications


                  Progress 01/01/87 to 12/30/87

                  Outputs
                  Texas peanut breeding line Tx771174 has been proposed for release as a new runner variety. In 20 tests since 1980, "1174" has been about 6% higher in gross value per acre than Florunner. The greater value has resulted from higher yields and grades. Maturity and disease susceptability were similar to Florunner. Progeny from the 7th backcross in the leafspot resistance introgression program were field tested for yield and resistance. Preliminary evaluations indicate some lines with acceptable resistance and high yield. The 8th backcross is presently being made. Almost 1500 germplasm lines were field screened for Sclerotinia resistance. Ninety lines were selected for further testing. Twelve breeding lines and varieties were field tested in Sclerotinia infested soil. Two breeding lines showed good potential. The same lines have tested well in other locations. In a test for chemical control of Sclerotinia on the Langley variety, one chemical increased wet weight yields from 335 Kg ha for the check to almost 2200 Kg ha. An additional cross was made in a modified convergent crossing program in which genes for yield, pod rot resistance, leafspot resistance, drought tolerance, and early maturity are being brought together into one group of lines. An additional 250 germplasm lines were field screened for rust and leafspot resistance. Selections were made for further testing. Seed of 300+ germplasm lines were provided to the USDA Regional Plant Introduction Station.

                  Impacts
                  (N/A)

                  Publications


                    Progress 01/01/86 to 12/30/86

                    Outputs
                    Breeding line TP-107-3-8 was released as 'Langley', a runner market type cultivar which yields equal to 'Florunner' but matures 7 to 14 days earlier. Date of harvest data confirmed Langley does not lose pods any faster than Florunner, just earlier. Seed will be available for commercial production in 1987. The 7th backcross was accomplished in a program to introgress leafspot resistance from wild Arachis into cultivated peanut. Progeny from BC(6)F(2) were field screened; resistance was noted for leafspot, rust and sclerotinia. No resistance was observed for tomato spotted wilt virus (TSWV). Progeny from intermediate steps in a convergent crossing program revealted some resistance to sclerotinia. The final cross in this program was accomplished; progeny will be advanced to F(5) by accelerated techniques of single-seed-descent and greenhouse growth. Another 250 germplasm lines from the new collections in South America were screened for rust and leafspot resistance. Lines were selected for further testing. Additional germplasm lines were collected in Uruguay, Argentina and Brazil. Germplasm lines were multiplied and distributed to the USDA Regional Plant Introduction Station in Experiment, GA.

                    Impacts
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                    Publications


                      Progress 01/01/85 to 12/30/85

                      Outputs
                      The actual start date of this project was 01 SEPT. 1985. Therefore, this reportwill be limited to stating of the project objectives and a status report: OBJECTIVES: Develop improved cultivars of peanut utilizing enhanced germplasm resources with leafspot resistance, pod rot resistance and early maturity. Develop new high-yielding peanut cultivars from novel approaches to crossing and selection, utilizing materials with multiple sources of resistance, high yield and early maturity. Evaluate new cultivars and germplasm collections for use in the Texas environments, specifically searching for drought tolerance, leafspot and pod rot resistance. Collect and maintain germplasm lines (introduced and developed) for future utilization. STATUS: A new early maturing runner peanut variety will be proposed for release in 1986. Segregating populations from multiple parent crosses will be evaluated and generations advanced. Leafspot resistant lines will be evaluated. Characterization will continue on new germplasm introductions.

                      Impacts
                      (N/A)

                      Publications