Progress 02/05/08 to 02/04/13
Outputs
Progress Report Objectives (from AD-416): The long-term objectives of this project are to identify and incorporate useful maize genetic diversity to support sustainable productivity of the most important crop in the United States, as measured by acreage planted, farm gate value, product value and strategic importance. To accomplish this, we will: 1) manage and coordinate a multi-site, cooperative program of maize germplasm evaluation, genetic enhancement, inbred line development, and information sharing focused on broadening the genetic base for U. S. maize; 2) evaluate maize germplasm with a broad spectrum of non-U.S. and mixed U.S./non-U.S. pedigrees for adaptation, yield, resistance to biotic and abiotic stresses, and key value-added traits; 3) breed and release genetically-enhanced populations and inbred lines, derived from non-U.S. and/or mixed U.S./non-U.S. germplasm sources, that are commercially-competitive and/or which contain key traditional or novel traits; and 4) develop innovative means of managing and transferring evaluation and breeding information to multiple project cooperators and germplasm users. Approach (from AD-416): Extensive collaboration efforts on the part of 60 current cooperators from the private, public and international sectors are required to broaden the germplasm base in effective ways that provide germplasm of use for food, feed, fuel, and industrial applications by producers and end-users. The Coordinator serves as the liaison for collaborators and the Technical Steering Group (TSG), selects germplasm, facilitates germplasm acquisition and stakeholder interactions, arranges for in-kind- support, information sharing, and technology transfer. The Ames location will develop germplasm derived from 50% and 25% exotic breeding crosses developed by crossing tropical and temperate racial accessions with adapted, elite proprietary Corn Belt lines. Approximately 1,500 -1,600 S2 top crosses will be made and evaluated annually in yield trials, disease nurseries, and for value-added traits such as ethanol, protein, oil, and starch. Germplasm will be further evaluated by a network of cooperators with expertise, facilities, and favorable selection environments for the traits of interest. Important traits include mycotoxin resistance, abiotic stress tolerance, and insect resistance. Germplasm lines will be released to cooperators and selected lines registered and publicly released. Released lines will be maintained by the National Plant Germplasm System's maize curator. An effort will be made to develop lines derived from approximately 250 races of maize to broadly represent the allelic diversity of the maize races. Initial crosses of racial accessions with expired PVP lines or other public lines are made in winter nurseries, and one backcross to the adapted line (BC1). The resulting BC1 generation will be used for selecting lines in Midwest nurseries in order to release a unique set of (F5 generation) adapted, racial derivative lines for research and discovery applications. Technologies and methodologies can be utilized such as SNP or SSR markers for genomic profiling and association analysis that offer potential to translate genomic knowledge to germplasm enhancement and utilization applications. Genotypes will be screened in selected environments to maximize selection for priority agronomic, biotic and abiotic stress, reduced mycotoxin, and value-added traits. This is the final report of the project. A new five year Plan was prepared and certified on April 3, 2013. Eight new GEM releases were distributed to cooperators for the 2013 planting season and 68 total releases during the period 2008-2012. Over the project's 20 year history 258 lines have been released by the GEM Project network of which 190 are publicly available through the Genetic Resources Information Network (GRIN). Approximately 10,700 yield trial plots were planted in 2013 at 46 trial locations with the combined effort of the GEM Project and 11 private cooperators. During the past five years approximately 78,000 yield trial plots (approximately 14,000 entries) were coordinated through Ames. Yield trials were planted at four locations for over 400 entries (top crosses) derived from CUBA164 X B73) x B73, and CUBA164 x PHB47) x PHB47. Objectives of this project include mapping the genes involved in adaptation to high plant density. The evaluation of breeding crosses is an important objective to determine adaptability and prioritization of exotic material for development. One hundred breeding crosses were planted in 2013, and approximately 100 per year for the past five years through in kind support from two cooperators, AgReliant and G and S Crop Services. A shade house was constructed in 2013 to reduce photoperiod response in tropical germplasm in order for crosses to be made to temperate germplasm. Approximately 50 tropical x temperate crosses will be made in 2013 using the shade house. During the past five years 278 tropical x temperate crosses were made using the shade house. The objective of the Allelic Diversity (AD) project is to develop and release adapted exotic germplasm representing ~300 races of maize using traditional selfing and doubled haploid (DH) technology. Approximately 175 rows were planted for traditional self pollination of segregating AD families, and 1,158 rows for seed increase of DH lines. The DH lines represent 252 inbreds which are being increased for public distribution to the maize research community. In addition, approximately 300 rows of nursery were planted to support development of a new haploid inducer inbred with better adaptation to the Midwest than the inducer line currently being used. A random mating nursery was planted in Ames to study if exotic alleles are less likely to survive the DH process if the original BC1 populations (versus random mated BC1's) are used for haploid induction. The study includes 22 BC1-sib 1 families. The objective of this project is to continue the second cycle of sib mating to make the BC1-sib2 that would be used for haploid induction the next season. Accomplishments 01 New sources of doubled haploid (DH) inbreds. The corn germplasm base in the U.S. is extremely narrow and lack of genetic diversity can lead to genetic vulnerability to pathogens and insects, and limit genetic gain from selection. An important source of exotic germplasm are inbred lines that are uniform, consistently breed true by self pollination, and have a fixed set of chromosomes contributed equally by each parent. Inbred lines are "diploid"(carry two sets of the basic chromosome number) and each parent contributes half the chromosome number or "haploid" set. ARS scientists in Ames utilize doubled haploid (DH) technology which is a genetic method to create haploids followed by doubling the chromosomes to develop completely homozygous, diploid inbreds. More than 15,000 self pollinations were made in 2013 to increase seed of 252 DH inbreds representative of 52 maize races which will be made available to the maize community. Utilization of DH technology accelerates the inbreeding process by reducing cycle time from the traditional 8 generations to 3 generations, and will provide unique adapted genetic resources to support agronomic improvement, gene discovery. Findings from use of this germplasm (which contains alleles introgressed from tropical germplasm) may contribute to increasing the diversity of commercial maize.
Impacts
(N/A)
Publications
- Henry, W.B., Windham, G.L., Rowe, D.E., Blanco, M.H., Murray, S.C., Williams, W.P. 2013. Diallel analysis of diverse maize germplasm lines for resistance to aflatoxin accumulation. Crop Science. 53:394-402.
- Yangcheng, H., Jiang, H., Blanco, M.H., Jane, J. 2013. Characterization of normal and waxy corn starch for bioethanol production. Journal of Agricultural and Food Chemistry. 61:379-386.
- Ni, X., Xu, W., Blanco, M.H., Wilson, J.P. 2012. Evaluation of corn germplasm lines for multiple ear-colonizing insect and disease resistance. Journal of Economic Entomology. 105:1457-1464.
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Progress 10/01/11 to 09/30/12
Outputs
Progress Report Objectives (from AD-416): The long-term objectives of this project are to identify and incorporate useful maize genetic diversity to support sustainable productivity of the most important crop in the United States, as measured by acreage planted, farm gate value, product value and strategic importance. To accomplish this, we will: 1) manage and coordinate a multi-site, cooperative program of maize germplasm evaluation, genetic enhancement, inbred line development, and information sharing focused on broadening the genetic base for U. S. maize; 2) evaluate maize germplasm with a broad spectrum of non-U.S. and mixed U.S./non-U.S. pedigrees for adaptation, yield, resistance to biotic and abiotic stresses, and key value-added traits; 3) breed and release genetically-enhanced populations and inbred lines, derived from non-U.S. and/or mixed U.S./non-U.S. germplasm sources, that are commercially-competitive and/or which contain key traditional or novel traits; and 4) develop innovative means of managing and transferring evaluation and breeding information to multiple project cooperators and germplasm users. Approach (from AD-416): Extensive collaboration efforts on the part of 60 current cooperators from the private, public and international sectors are required to broaden the germplasm base in effective ways that provide germplasm of use for food, feed, fuel, and industrial applications by producers and end-users. The Coordinator serves as the liaison for collaborators and the Technical Steering Group (TSG), selects germplasm, facilitates germplasm acquisition and stakeholder interactions, arranges for in-kind- support, information sharing, and technology transfer. The Ames location will develop germplasm derived from 50% and 25% exotic breeding crosses developed by crossing tropical and temperate racial accessions with adapted, elite proprietary Corn Belt lines. Approximately 1,500 -1,600 S2 top crosses will be made and evaluated annually in yield trials, disease nurseries, and for value-added traits such as ethanol, protein, oil, and starch. Germplasm will be further evaluated by a network of cooperators with expertise, facilities, and favorable selection environments for the traits of interest. Important traits include mycotoxin resistance, abiotic stress tolerance, and insect resistance. Germplasm lines will be released to cooperators and selected lines registered and publicly released. Released lines will be maintained by the National Plant Germplasm System's maize curator. An effort will be made to develop lines derived from approximately 250 races of maize to broadly represent the allelic diversity of the maize races. Initial crosses of racial accessions with expired PVP lines or other public lines are made in winter nurseries, and one backcross to the adapted line (BC1). The resulting BC1 generation will be used for selecting lines in Midwest nurseries in order to release a unique set of (F5 generation) adapted, racial derivative lines for research and discovery applications. Technologies and methodologies can be utilized such as SNP or SSR markers for genomic profiling and association analysis that offer potential to translate genomic knowledge to germplasm enhancement and utilization applications. Genotypes will be screened in selected environments to maximize selection for priority agronomic, biotic and abiotic stress, reduced mycotoxin, and value-added traits. Severe drought and heat in all Midwest states will impact trial results and the productivity of the Ames nursery; extent of losses will not be known until harvest. Six new GEM releases were distributed to cooperators for the 2012 season. One release, GEMS-0226, had protein content of 13.4% (vs 9-10% for most Corn Belt hybrids). Presently, 244 lines have been released by the GEM Project, of which 170 are publicly available via the Genetic Resources Information Network (GRIN). Approximately 13,100 yield trial plots were planted at 46 trial locations with the combined efforts of the GEM Project and 12 private cooperators. The evaluation of breeding crosses is an important objective to determine adaptability and prioritization of exotic material for development. One hundred breeding crosses were planted at three locations in 2012 in collaboration with two cooperators, AgReliant, and G and S Crop Services. The objective of the Allelic Diversity (AD) project is to develop adapted exotic inbred lines representing ~300 races of maize. To achieve this objective, traditional selfing and doubled haploid methods are used. Approximately 594 nursery rows were devoted to traditional selfing of AD germplasm, comprised of 115 races from 14 countries in 2012. More than 300 accessions from 200 races are in use in the AD project's developmental pipeline. The haploid inducer line currently used is very early, has low seed yield, and is not adapted to the Midwest. Breeding efforts to develop a new inducer consisted of 90 rows of S3 families that were self pollinated and crossed to a tester line to evaluate their potential as new haploid inducer lines. A testcross isolation block of 452 BC1S2 families of a CUBA164 mapping population was planted in collaboration with Pioneer Hi-Bred, a DuPont business. This includes an equal number of BC1S2 families from CUBA164 x B73) x B73, and BC1S2 families from CUBA164 x PHB47) x PHB47 (~226 families each). Future objectives of this project include identification and mapping of genes involved in adaptation to high plant density, and distribution to the maize community for other studies. Aflatoxin content: two lines were identified with reduced content in collaboration with the USDA-ARS Corn Host Plant Resistance Research Unit (CHPRRU) in Starkville, MS. Inbred KO679Y (PI 591017), and GEM inbred CUBA117:S15-101-1-B-B-B-B were reported to contribute to reduced content in crosses with two inbreds developed by CHPRRU, Mp717 and Mp794, and with other two GEM lines, GEMN- 0130 and GEMN-0140. (Henry et al. 2012). Additional crosses with KO679Y and CUBA117:S15-101-1-B-B-B-B were made in the 2012 nursery for future use. Accomplishments 01 New sources of Doubled Haploid (DH) inbreds. The corn germplasm base in the U.S. is extremely narrow and lack of genetic diversity can lead to genetic vulnerability to pathogens and insects, and limit genetic gain from selection. The Germplasm Enhancement of Maize (GEM) Project utilize doubled haploid (DH) technology to expedite development of inbreds from populations derived from exotic races. In the past year, 38 additional inbreds from 11 races were developed; 417 total DH inbreds now represent 85 maize races. The DH lines are being increased in 2012 for future research and distribution to the maize community. Utilization of DH technology accelerates the inbreeding process by reducing cycle time fro the traditional 8 generations to 3 generations, and will provide valuabl genetic resources to broaden the germplasm base with potentially unique alleles.
Impacts
(N/A)
Publications
- Brenner, E., Blanco, M.H., Gardner, C.A., Lubberstedt, T. 2012. Genotypic and phenotypic characterization of isogenic doubled haploid exotic introgression lines in maize. Molecular Breeding. 30:1001-1016. Available:
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Progress 10/01/10 to 09/30/11
Outputs
Progress Report Objectives (from AD-416) The long-term objectives of this project are to identify and incorporate useful maize genetic diversity to support sustainable productivity of the most important crop in the United States, as measured by acreage planted, farm gate value, product value and strategic importance. To accomplish this, we will: 1) manage and coordinate a multi-site, cooperative program of maize germplasm evaluation, genetic enhancement, inbred line development, and information sharing focused on broadening the genetic base for U. S. maize; 2) evaluate maize germplasm with a broad spectrum of non-U.S. and mixed U.S./non-U.S. pedigrees for adaptation, yield, resistance to biotic and abiotic stresses, and key value-added traits; 3) breed and release genetically-enhanced populations and inbred lines, derived from non-U.S. and/or mixed U.S./non-U.S. germplasm sources, that are commercially-competitive and/or which contain key traditional or novel traits; and 4) develop innovative means of managing and transferring evaluation and breeding information to multiple project cooperators and germplasm users. Approach (from AD-416) Extensive collaboration efforts on the part of 60 current cooperators from the private, public and international sectors are required to broaden the germplasm base in effective ways that provide germplasm of use for food, feed, fuel, and industrial applications by producers and end-users. The Coordinator serves as the liaison for collaborators and the Technical Steering Group (TSG), selects germplasm, facilitates germplasm acquisition and stakeholder interactions, arranges for in-kind- support, information sharing, and technology transfer. The Ames location will develop germplasm derived from 50% and 25% exotic breeding crosses developed by crossing tropical and temperate racial accessions with adapted, elite proprietary Corn Belt lines. Approximately 1,500 -1,600 S2 top crosses will be made and evaluated annually in yield trials, disease nurseries, and for value-added traits such as ethanol, protein, oil, and starch. Germplasm will be further evaluated by a network of cooperators with expertise, facilities, and favorable selection environments for the traits of interest. Important traits include mycotoxin resistance, abiotic stress tolerance, and insect resistance. Germplasm lines will be released to cooperators and selected lines registered and publicly released. Released lines will be maintained by the National Plant Germplasm System's maize curator. An effort will be made to develop lines derived from approximately 250 races of maize to broadly represent the allelic diversity of the maize races. Initial crosses of racial accessions with expired PVP lines or other public lines are made in winter nurseries, and one backcross to the adapted line (BC1). The resulting BC1 generation will be used for selecting lines in Midwest nurseries in order to release a unique set of (F5 generation) adapted, racial derivative lines for research and discovery applications. Technologies and methodologies can be utilized such as SNP or SSR markers for genomic profiling and association analysis that offer potential to translate genomic knowledge to germplasm enhancement and utilization applications. Genotypes will be screened in selected environments to maximize selection for priority agronomic, biotic and abiotic stress, reduced mycotoxin, and value-added traits. Progress was made on all four objectives and sub-objectives. An important objective is the development of adapted exotic inbred lines representing 300 races of maize using double haploid and traditional plant breeding methods. Through the combined support of two private Germplasm Enhancement of Maize (GEM) cooperators, 400 rows of doubled haploid (DH) families developed in Ames, IA, were planted in two tropical winter nurseries to increase seed for the 2011 nursery. Approximately 300 DH families were returned and planted for seed increase. In addition, 38 new haploid populations representing 28 races (1,710 plants) were treated at the 3-leaf stage with a chromosome doubling agent, colchicine, grown by the Iowa State University (ISU) Doubled Haploid Facility for two more weeks, and transplanted in the nursery. To enhance our ability to detect haploid plants we initiated development of a new haploid inducer line using a yellow dominant mutant received from the Maize Genetics Stock Center. (The current genetic marker is not detectable in many exotic backgrounds due to color inhibitor genes). For the traditional breeding program, approximately 504 nursery rows were devoted to the Allelic Diversity (AD) project which comprised 110 races from 13 countries. Presently, 187 races from 227 accessions are at the first backcross (BC1) stage, and approximately 10 populations are at the F5 or later inbreeding generation. Approximately 16,500 yield trial plots were planted at 53 trial locations with the combined efforts of the GEM Project and 12 private cooperators. Efforts continue to create an exotic mapping population using CUBA164 (PI 489361) as the elite exotic source identified in the GEM Project. Approximately 230 S2 families from (CUBA164 x B73) x B73, and 230 S2 families from (CUBA164 x PHB47) x PHB47 were planted in the LH287 iso to make test crosses. Research continued utilizing the shade structure to make new tropical x temperate crosses in Ames. In addition to 40 tropical maize sources, two teosinte subspecies (parviglumis and mexicana) were planted to determine if early flowering can be induced under shade structures. Seed was increased of four host differentials for Southern Rust known to have the Rpp9 gene. This is a cooperative effort with the Agricultural Research Service (ARS) Maize Curator, Pioneer Hi-Bred, and ARS researchers at Raleigh, NC and various universities. Two new cooperators joined the GEM Project: Semillas Fito SA, a private cooperator from Spain, and Genetic Resources, Inc, a private U.S. cooperator. The new cooperators will expand our access to exotic European germplasm, provide virus disease data for Spain, and enhance our ability to evaluate normal and high amylose starch germplasm in the U.S. Other research collaborations in progress with the public and private sectors include germplasm evaluation and/or development with nine universities, two private companies, and five USDA-ARS research units for mycotoxin, abiotic stress, southern leaf blight, grey leafspot, corn root worm, multiple insect resistance, and starch properties for ethanol potential, digestibility, and resistant starch for human health applications. Accomplishments 01 New sources of germplasm. The corn germplasm base in the U.S. is extreme narrow, and lack of genetic diversity can lead to genetic vulnerability pathogens and insects, and limit genetic gain from selection. The Germplasm Enhancement of Maize (GEM) Project utilizes traditional breedi and double haploid (DH) induction technology to expedite development of inbreds from exotic races. From the traditional breeding program Agricultural Research Service researchers in Ames, IA, released 6 lines for 2011. Two of the lines had protein levels above 13% (normal is 9-10% and were derived from crosses involving two GEM inbreds (second cycle). From the DH research, 379 finished inbreds representing 74 exotic races were increased in the nursery and will be valuable sources of diversity which can potentially broaden the germplasm base. Disease screening efforts by the network identified materials with exceptional resistance Fusarium ear mold. Utilization of adapted germplasm by university researchers is designed to provide new knowledge and technology related exotic germplasm. Use of DH technology with useful exotic germplasm reduces breeding cycle time from the traditional 8 generations of inbreeding to 3 generations. Shortening breeding cycle time provides opportunity to increase the rate of genetic gain per year. An increased rate of genetic gain enables more rapid deployment of genes/traits/varieties to address production issues and food security.
Impacts
(N/A)
Publications
- Jiang, H., Lio, J., Blanco, M.H., Campbell, M., Jane, J. 2010. Resistant- starch Formation in High-amylose Maize Starch During Kernel Development. Journal of Agriculture and Food Chemistry. 58:8043-8047.
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Progress 10/01/09 to 09/30/10
Outputs
Progress Report Objectives (from AD-416) The long-term objectives of this project are to identify and incorporate useful maize genetic diversity to support sustainable productivity of the most important crop in the United States, as measured by acreage planted, farm gate value, product value and strategic importance. To accomplish this, we will: 1) manage and coordinate a multi-site, cooperative program of maize germplasm evaluation, genetic enhancement, inbred line development, and information sharing focused on broadening the genetic base for U. S. maize; 2) evaluate maize germplasm with a broad spectrum of non-U.S. and mixed U.S./non-U.S. pedigrees for adaptation, yield, resistance to biotic and abiotic stresses, and key value-added traits; 3) breed and release genetically-enhanced populations and inbred lines, derived from non-U.S. and/or mixed U.S./non-U.S. germplasm sources, that are commercially-competitive and/or which contain key traditional or novel traits; and 4) develop innovative means of managing and transferring evaluation and breeding information to multiple project cooperators and germplasm users. Approach (from AD-416) Extensive collaboration efforts on the part of 60 current cooperators from the private, public and international sectors are required to broaden the germplasm base in effective ways that provide germplasm of use for food, feed, fuel, and industrial applications by producers and end-users. The Coordinator serves as the liaison for collaborators and the Technical Steering Group (TSG), selects germplasm, facilitates germplasm acquisition and stakeholder interactions, arranges for in-kind- support, information sharing, and technology transfer. The Ames location will develop germplasm derived from 50% and 25% exotic breeding crosses developed by crossing tropical and temperate racial accessions with adapted, elite proprietary Corn Belt lines. Approximately 1,500 -1,600 S2 top crosses will be made and evaluated annually in yield trials, disease nurseries, and for value-added traits such as ethanol, protein, oil, and starch. Germplasm will be further evaluated by a network of cooperators with expertise, facilities, and favorable selection environments for the traits of interest. Important traits include mycotoxin resistance, abiotic stress tolerance, and insect resistance. Germplasm lines will be released to cooperators and selected lines registered and publicly released. Released lines will be maintained by the National Plant Germplasm System's maize curator. An effort will be made to develop lines derived from approximately 250 races of maize to broadly represent the allelic diversity of the maize races. Initial crosses of racial accessions with expired PVP lines or other public lines are made in winter nurseries, and one backcross to the adapted line (BC1). The resulting BC1 generation will be used for selecting lines in Midwest nurseries in order to release a unique set of (F5 generation) adapted, racial derivative lines for research and discovery applications. Technologies and methodologies can be utilized such as SNP or SSR markers for genomic profiling and association analysis that offer potential to translate genomic knowledge to germplasm enhancement and utilization applications. Genotypes will be screened in selected environments to maximize selection for priority agronomic, biotic and abiotic stress, reduced mycotoxin, and value-added traits. Progress was made on all four objectives and sub-objectives. On July 18, a severe wind storm in excess of 70 mph caused significant damage to various sections of the GEM nursery. The extent of damage ranged from as high as ~30% in some sections to about 5% in other sections of the nursery. Overall, approximately 15% of the 6,400 nursery rows were wind- snapped or severely root lodged making pollinations impossible or very difficult to reach the intended number required. As a result, an increase in winter nursery use will be necessary. An important objective is the development of adapted exotic inbred lines representing 300 races of maize using double haploid and traditional plant breeding methods. Through the combined support of two private GEM cooperators, 423 rows of doubled haploid (DH) families developed in Ames, IA, were planted in winter nurseries in Hawaii and Chile to increase seed for the 2010 GEM nursery. Approximately 300 DH families were returned from the two winter nurseries and planted for seed increase. In addition, 78 new haploid populations representing 42 races (4,030 plants) were treated at the three leaf stage with a chromosome doubling agent, colchicine, grown in the greenhouse for two weeks, and transplanted in the nursery. Since haploid tassels are very sensitive to intense sunlight, an overhead temporary shade structure (18 feet x 360 feet) was constructed above the haploid plants to reduce sun light intensity by 30%. (The shade structure was destroyed by the windstorm of July 18). Approximately 319 plants were identified as potential doubled haploids and self pollinated before the wind storm. For the traditional breeding program, approximately 419 nursery rows were devoted to the Allelic Diversity (AD) project which comprised 85 races from 10 countries. Presently, 176 races from 189 accessions are at the first back cross (BC1) stage (or later generation of inbreeding). Approximately 17,700 yield trial plots were planted at 49 trial locations with the combined effort of the GEM Project and 14 private cooperators. Efforts are continuing to create an exotic mapping population using CUBA164 (PI 489361) as the elite exotic source identified in the GEM Project. The second selfing (S2) generation was made from the backcross (BC) families to create the BC1S2 generation of 241 families of (CUBA164 x B73) x B73, and 241 families (CUBA164 x PHB47) x PHB47. Two new cooperators joined the Germplasm Enhancement of Maize (GEM) Project. Semilia Genetica, a private cooperator from Brazil, and the Louisiana State University Agricultural Center. The new cooperators will expand our access to exotic tropical germplasm, and enhance our ability to evaluate germplasm for aflatoxin resistance. Other research collaborations in progress with the public and private sectors include germplasm evaluation and/or development with nine Universities, two private companies, and five USDA-ARS research units for mycotoxin, abiotic stress, southern leaf blight, grey leafspot, corn root worm, multiple insect resistance, amino acid evaluation, and starch properties for ethanol potential and resistant starch. Accomplishments 01 Doubled Haploid's (DH) of allelic diversity germplasm. An important objective of the allelic diversity project is to capture the genetic variation represented in over 300 exotic corn races. This requires an extensive adaptation process by crossing exotic maize races to Corn Belt germplasm followed by selection and inbreeding. Collaborating with Iowa State University scientists, GEM ARS researchers at the Plant Introducti Unit in Ames, IA, implemented a DH method to attain homozygous uniform plants in two growing seasons versus the 8-10 seasons normally required for traditional inbreeding. Beginning in 2008, breeding populations from the GEM allelic diversity project were crossed to an inducer to make haploids (plants with half the chromosome number), and were doubled the following year to attain diploid homozygous (uniform) plants. Approximately 300 inbred lines representing 44 races were identified and planted for increase in 2010. This accomplishment can accelerate development of adapted inbreds derived from ~300 exotic races and potentially provide valuable genetic resources to the maize community.
Impacts
(N/A)
Publications
- Srichuwong, S., Gutsea, J., Blanco, M.H., Duvick, S.A., Gardner, C.A., Jane, J. 2010. Characterization of Corn Grains for Ethanol Production. Journal of ASTM International. 7(2):1-10.
- Jiang, H., Campbell, M., Blanco, M.H., Jane, J. 2010. Characterization of Maize Amylose-extender (ae) Mutant Starches. Part II: Structures and Properties of Starch Residues Remaining After Enzymatic Hydrolyis at Boiling-water Temperature. Carbohydrate Polymers. 80(1):1-12.
- Jiang, H., Horner, H.T., Pepper, T.M., Blanco, M.H., Campbell, M., Jane, J. 2010. Formation of Elongated Starch Granules in High-amylose Maize. Carbohydrate Polymers. 80(2):534-539.
- Scott, M.P., Blanco, M.H. 2009. Evaluation of the Methionine Content of Maize (Zea mays L.) Germplasm in the Germplasm Enhancement of Maize Program. Plant Genetic Resources. 7:237-243.
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Progress 10/01/08 to 09/30/09
Outputs
Progress Report Objectives (from AD-416) The long-term objectives of this project are to identify and incorporate useful maize genetic diversity to support sustainable productivity of the most important crop in the United States, as measured by acreage planted, farm gate value, product value and strategic importance. To accomplish this, we will: 1) manage and coordinate a multi-site, cooperative program of maize germplasm evaluation, genetic enhancement, inbred line development, and information sharing focused on broadening the genetic base for U. S. maize; 2) evaluate maize germplasm with a broad spectrum of non-U.S. and mixed U.S./non-U.S. pedigrees for adaptation, yield, resistance to biotic and abiotic stresses, and key value-added traits; 3) breed and release genetically-enhanced populations and inbred lines, derived from non-U.S. and/or mixed U.S./non-U.S. germplasm sources, that are commercially-competitive and/or which contain key traditional or novel traits; and 4) develop innovative means of managing and transferring evaluation and breeding information to multiple project cooperators and germplasm users. Approach (from AD-416) Extensive collaboration efforts on the part of 60 current cooperators from the private, public and international sectors are required to broaden the germplasm base in effective ways that provide germplasm of use for food, feed, fuel, and industrial applications by producers and end-users. The Coordinator serves as the liaison for collaborators and the Technical Steering Group (TSG), selects germplasm, facilitates germplasm acquisition and stakeholder interactions, arranges for in-kind- support, information sharing, and technology transfer. The Ames location will develop germplasm derived from 50% and 25% exotic breeding crosses developed by crossing tropical and temperate racial accessions with adapted, elite proprietary Corn Belt lines. Approximately 1,500 -1,600 S2 top crosses will be made and evaluated annually in yield trials, disease nurseries, and for value-added traits such as ethanol, protein, oil, and starch. Germplasm will be further evaluated by a network of cooperators with expertise, facilities, and favorable selection environments for the traits of interest. Important traits include mycotoxin resistance, abiotic stress tolerance, and insect resistance. Germplasm lines will be released to cooperators and selected lines registered and publicly released. Released lines will be maintained by the National Plant Germplasm System's maize curator. An effort will be made to develop lines derived from approximately 250 races of maize to broadly represent the allelic diversity of the maize races. Initial crosses of racial accessions with expired PVP lines or other public lines are made in winter nurseries, and one backcross to the adapted line (BC1). The resulting BC1 generation will be used for selecting lines in Midwest nurseries in order to release a unique set of (F5 generation) adapted, racial derivative lines for research and discovery applications. Technologies and methodologies can be utilized such as SNP or SSR markers for genomic profiling and association analysis that offer potential to translate genomic knowledge to germplasm enhancement and utilization applications. Genotypes will be screened in selected environments to maximize selection for priority agronomic, biotic and abiotic stress, reduced mycotoxin, and value-added traits. Significant Activities that Support Special Target Populations Seven new cooperators joined the Germplasm Enhancement of Maize (GEM) Project. Three were from private U.S. companies, two private International (MayAgro Seed Corp from Turkey; Biomatrix Ltda from Brazil), one U.S. public university (Texas A&M), and the USDA-ARS Crop Genetics and Production Research Unit in Stoneville, MS. The new cooperators will expand our access to exotic germplasm by making new breeding crosses, and enhance our ability to evaluate and develop germplasm for reduced levels of mycotoxin. Other research collaborations in progress with the public sector include germplasm evaluation and development with five USDA-ARS research units (Crop Genetics and Breeding Research Unit, Corn Host Plant Resistance Research Unit, Corn Insects and Crop Genetics Research Unit, Plant Genetics Research Unit, and Plant Science Research Unit) for mycotoxin, southern leaf blight, grey leafspot, corn root worm, multiple insect resistance, amino acid evaluation, and starch properties for ethanol potential. Approximately 8,254 nursery rows and 300 demonstration plots were planted in Ames, IA by the GEM Project, and 14, 390 yield trial plots planted at 56 trial locations with the combined effort of the GEM Project and 13 private cooperators. To maximize nursery resources 24 S1 families were planted as single seed descent (SSD) balanced bulks which resulted in reducing the number of nursery rows from 6,000 to 408. Approximately 369 nursery rows were devoted to the Allelic Diversity (AD) project which comprised 70 races from 10 countries. In addition, approximately 677 rows were planted to potential haploid families in 2009 which were generated last year and identified this winter by scoring kernels for the presence of a marker on the seed cap. Approximately 413 rows were planted for induction of new haploid lines for the 2009 season. Studies were also initiated for methods of doubling chromosome numbers to make double haploids (DH) without the use of colchicine. The DH technology has not been extensively explored with exotic germplasm and has great potential to enhance progress for rapid release of adapted lines derived from racial materials. Efforts are continuing to create an exotic mapping population using CUBA164 (PI 489361) as the elite exotic source identified in the GEM Project. The first selfing (S1) generation was made from the backcross (BC) families to create the BC1S1 generation of 248 families of (CUBA164 x B73) x B73, and 248 families (CUBA164 x PHB47) x PHB47. Technology Transfer Number of Web Sites managed: 1 Number of Other Technology Transfer: 2
Impacts
(N/A)
Publications
- Li, L., Jiang, H., Campbell, M., Blanco, M.H., Jane, J. 2008. Characterization of Maize Amylose-Extender (ae) Mutant Starches. Part I: Relationship Between Resistant Starch Contents and Molecular Structures. Carbohydrate Polymers. 74(3):396-404.
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Progress 10/01/07 to 09/30/08
Outputs
Progress Report Objectives (from AD-416) The long-term objectives of this project are to identify and incorporate useful maize genetic diversity to support sustainable productivity of the most important crop in the United States, as measured by acreage planted, farm gate value, product value and strategic importance. To accomplish this, we will: 1) manage and coordinate a multi-site, cooperative program of maize germplasm evaluation, genetic enhancement, inbred line development, and information sharing focused on broadening the genetic base for U. S. maize; 2) evaluate maize germplasm with a broad spectrum of non-U.S. and mixed U.S./non-U.S. pedigrees for adaptation, yield, resistance to biotic and abiotic stresses, and key value-added traits; 3) breed and release genetically-enhanced populations and inbred lines, derived from non-U.S. and/or mixed U.S./non-U.S. germplasm sources, that are commercially-competitive and/or which contain key traditional or novel traits; and 4) develop innovative means of managing and transferring evaluation and breeding information to multiple project cooperators and germplasm users. Approach (from AD-416) Extensive collaboration efforts on the part of 60 current cooperators from the private, public and international sectors are required to broaden the germplasm base in effective ways that provide germplasm of use for food, feed, fuel, and industrial applications by producers and end-users. The Coordinator serves as the liaison for collaborators and the Technical Steering Group (TSG), selects germplasm, facilitates germplasm acquisition and stakeholder interactions, arranges for in-kind- support, information sharing, and technology transfer. The Ames location will develop germplasm derived from 50% and 25% exotic breeding crosses developed by crossing tropical and temperate racial accessions with adapted, elite proprietary Corn Belt lines. Approximately 1,500 -1,600 S2 top crosses will be made and evaluated annually in yield trials, disease nurseries, and for value-added traits such as ethanol, protein, oil, and starch. Germplasm will be further evaluated by a network of cooperators with expertise, facilities, and favorable selection environments for the traits of interest. Important traits include mycotoxin resistance, abiotic stress tolerance, and insect resistance. Germplasm lines will be released to cooperators and selected lines registered and publicly released. Released lines will be maintained by the National Plant Germplasm System's maize curator. An effort will be made to develop lines derived from approximately 250 races of maize to broadly represent the allelic diversity of the maize races. Initial crosses of racial accessions with expired PVP lines or other public lines are made in winter nurseries, and one backcross to the adapted line (BC1). The resulting BC1 generation will be used for selecting lines in Midwest nurseries in order to release a unique set of (F5 generation) adapted, racial derivative lines for research and discovery applications. Technologies and methodologies can be utilized such as SNP or SSR markers for genomic profiling and association analysis that offer potential to translate genomic knowledge to germplasm enhancement and utilization applications. Genotypes will be screened in selected environments to maximize selection for priority agronomic, biotic and abiotic stress, reduced mycotoxin, and value-added traits. Significant Activities that Support Special Target Populations This is the first report of the new Project and covers the period February 5, 2008 until September 30, 2008. Six new cooperators joined the Germplasm Enhancement of Maize (GEM) Project. Four were from private U.S. companies, one public International (Chinese Academy of Agricultural Sciences), and the USDA-ARS Mycotoxin Research Unit in Peoria, IL. The new cooperators will expand our access to exotic germplasm by making new breeding crosses, and enhance our ability to evaluate and develop germplasm for reduced levels of mycotoxin. Other research collaborations in progress with the public sector included germplasm evaluation and development with five USDA-ARS research units (Crop Genetics and Breeding Research Unit, Corn Host Plant Resistance Research Unit, Corn Insects and Crop Genetics Research Unit, Plant Genetic Resources Unit, and Plant Science Research Unit) for mycotoxin, southern leaf blight, grey leafspot, corn root worm, multiple and amino acid evaluation and starch properties for ethanol potential. The 2008 planting season was a challenge due to the Midwest floods and some plots were planted late, and/or flood damaged (less than 5% overall). Approximately 5,825 nursery rows and 300 demonstration plots were planted in Ames, IA by the GEM Project, and 17, 833 yield trial plots planted with the combined effort of the GEM Project and 16 private cooperators at 57 trial locations. To maximize nursery resources 22 S1 families were planted as single seed descent (SSD) balanced bulks which resulted in reducing the number of nursery rows from 5,500 to 370. Approximately, 466 nursery rows were devoted to the Allelic Diversity (AD) project which comprised 39 races from 11 countries. A new technology applied to the AD project was making crosses with a double haploid (DH) inducer working with a cooperator at the Iowa State University Agronomy Department. Following harvest, individual ears will be examined and selected for DH kernels for future chromosome doubling. This technology has not been extensively explored with exotic germplasm and has great potential to enhance progress for rapid release of adapted lines derived from racial materials. Research is also continuing on the applicability of using shade houses to reduce photoperiod response in 19 exotic tropical germplasm sources. The first backcross (BC1) was made for 292 F1 families of CUBA164 to the two recurrent parents to create an elite exotic mapping population. Progress by the GEM Project relates to the National Program 301 Action Plan, Component 3, Genetic Improvement of Crops, Problem Statement 3C, Germplasm Enhancement/Release of Improved Genetic Resources and Varieties. Technology Transfer Number of Web Sites managed: 1 Number of Other Technology Transfer: 2
Impacts
(N/A)
Publications
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