Progress 05/07/08 to 04/08/13
Outputs
Progress Report Objectives (from AD-416): Objective 1: Identify and utilize fertility/sterility mutants in a phenotypic recurrent selection program for insect-mediated cross- pollination to increase hybrid seed production. Objective 2: Identify phenotypes/genotypes that can be characterized and molecularly mapped that contribute to insect-pollinator attraction and reward. Approach (from AD-416): Soybean accessions in the USDA germplasm collection will be crossed with known cytoplasmic restorer lines to identify cytoplasmic male sterile cytoplasms. Sterility mutants (nuclear) obtained via gene tagging from the w4-mutable system will be characterized genetically. Both the cytoplasmic and nuclear sterility mutants will be used in a phenotypic recurrent selection system, with insect-mediated cross-pollination, to increase hybrid seed production. The plant factors that contribute to the increased attraction/reward of the insect pollinators will be identified, characterized, and molecularly mapped. Identification of soybean germplasm with cytoplasmic male-sterility (CMS) will be useful to produce hybrid soybean seed commercially. We molecularly mapped all male-sterile and female-sterile mutants in the ARS germplasm collection. The location of these sterility mutants expands our knowledge about the chromosomal distribution of sterility mutants. Surprisingly, clusters of sterility genes were identified in the genome, but the significance of clustering is not understood. Discovery and characterization of CMS and nuclear male sterility provides the genetic material to determine if hybrid production in soybean is possible and feasible. Hybrid seed should enhance agronomic performance and result in increased seed yield, and hopefully increased profits. The coordination of male and female development is necessary for seed production. Developmental delays may lead to sterility and affect seed formation. The effect of the environment on sterility is unknown. Determining what conditions lead to changes in seed production is essential for assessing their utility in soybean hybrid development. We tested the affect of day and night temperatures on the sterility. While day temperature altered seed count in the ms8ms8 mutant, night temperature altered seed count in the ms9ms9 mutant. The differential expression between male sterility and male fertility in these experiments is not sufficient to warrant large-scale production of F1 hybrid seed. However, breeding programs could use this system to produce small quantities of hybrid seed with increased efficiency. The recent release of the soybean genome sequence provides researchers additional information for plant improvement. However, integration of molecular biology with the classical genetics is not complete, as some genetic traits have not been assigned to chromosomes. Working with collaborators, we combined in situ hybridization with chromosome translocations to identify specific chromosomes. These findings are important to geneticists and breeders to identify which chromosome segments are rearranged, duplicated, or deleted. Traits of interest can be localized on a chromosome and these results will be used to characterize soybean germplasm and to identify and transfer desirable traits to breeding lines. New cultivars will be bred and improved cultivars will be available to the farmer that will offer better quality seeds, and resistance to biotic and abiotic stresses. Abiotic and biotic stresses impact plant production around the world. One of the most devastating pests is the whitefly. White flies cause damage through direct feeding and through the transmission of harmful viruses. Whiteflies have been reported on soybean in the United States and in certain areas in Mexico. Heavy soybean white fly infestations have resulted on a soybean ban in some areas. To determine the genetic basis of white fly resistance, we crossed two different resistant soybean lines with the same susceptible line. Multiple resistance QTLs were identified in the genome, suggesting resistance was conferred by several genes. White fly resistance QTL will help plant breeders breed resistance into improved cultivars.
Impacts
(N/A)
Publications
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Progress 10/01/11 to 09/30/12
Outputs
Progress Report Objectives (from AD-416): Objective 1: Identify and utilize fertility/sterility mutants in a phenotypic recurrent selection program for insect-mediated cross- pollination to increase hybrid seed production. Objective 2: Identify phenotypes/genotypes that can be characterized and molecularly mapped that contribute to insect-pollinator attraction and reward. Approach (from AD-416): Soybean accessions in the USDA germplasm collection will be crossed with known cytoplasmic restorer lines to identify cytoplasmic male sterile cytoplasms. Sterility mutants (nuclear) obtained via gene tagging from the w4-mutable system will be characterized genetically. Both the cytoplasmic and nuclear sterility mutants will be used in a phenotypic recurrent selection system, with insect-mediated cross-pollination, to increase hybrid seed production. The plant factors that contribute to the increased attraction/reward of the insect pollinators will be identified, characterized, and molecularly mapped. Cytoplasmic male sterility is a type of plant sterility that would greatly enhance hybrid breeding in soybean. In certain genetic backgrounds and environments, male sterility is not complete in soybean, therefore, additional crossing and testing are needed to identify stable sterility systems. In 2012, supposed maintainer and restorer soybean germplasm was grown in the field for seed increase to maintain the germplasm. Soybean accessions in the USDA germplasm collection were crossed with known cytoplasmic restorer lines to identify cytoplasmic male sterile germplasm. Approximately 200 cross-pollinations were made to initiate molecular mapping studies of all known male-sterile, female- fertile mutants. Evaluated approximately 2000 F2:3 progeny rows of 8 male-sterile, female-sterile mutants for molecular mapping to determine the genotype of F2 plants. These germplasms will be useful to plant breeders to develop hybrid soybean that are expected, after selection, to have superior agronomic performance.
Impacts
(N/A)
Publications
- Findley, S.D., Pappas, A.L., Cui, Y., Birchler, J.A., Palmer, R.G., Stacey, G. 2011. Fluorescence in situ hybridization-based karyotyping of soybean translocation lines. Genes, Genomes, Genetics. 1:117-129.
- Perez-Sackett, P.T., Palmer, R.G. 2012. Effect of day and night temperature on the expression of male sterility of nuclear male-sterile (ms8ms8) soybean. Euphytica. 186(3):847-853.
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Progress 10/01/10 to 09/30/11
Outputs
Progress Report Objectives (from AD-416) Objective 1: Identify and utilize fertility/sterility mutants in a phenotypic recurrent selection program for insect-mediated cross- pollination to increase hybrid seed production. Objective 2: Identify phenotypes/genotypes that can be characterized and molecularly mapped that contribute to insect-pollinator attraction and reward. Approach (from AD-416) Soybean accessions in the USDA germplasm collection will be crossed with known cytoplasmic restorer lines to identify cytoplasmic male sterile cytoplasms. Sterility mutants (nuclear) obtained via gene tagging from the w4-mutable system will be characterized genetically. Both the cytoplasmic and nuclear sterility mutants will be used in a phenotypic recurrent selection system, with insect-mediated cross-pollination, to increase hybrid seed production. The plant factors that contribute to the increased attraction/reward of the insect pollinators will be identified, characterized, and molecularly mapped. Progress was made on all objectives and their sub-objectives. More germplasm was used in cross-pollinations. Progress was made on cytoplasmic male sterility (a type of plant sterility that will greatly enhance hybrid breeding in soybean) in the USDA-ARS soybean germplasm. Unfortunately, in certain genetic backgrounds and environments, male sterility is not complete. This is a common occurrence in cytoplasmic male-sterile systems. In 2011, the search for maintainer and restorer soybean germplasm was initiated to preserve our supposed cytoplasmic male- sterile germplasm. Additional fertility/sterility mutants were molecularly mapped. Plant structure (floral display and floral design) and chemical traits associated with soybean insect-pollinator attraction and reward were identified and characterized. We used the proboscis extension response (PER) technique to train honeybees to differentiate among soybean genotypes selected on the basis of out-crossed seed-set. Soybean accessions in the USDA germplasm collection were crossed with known cytoplasmic restorer lines to identify cytoplasmic male sterile germplasm. Sterility mutants will be characterized genetically. Cytoplasmic (or extra-nuclear) and nuclear sterility mutants will be used in a plant breeding system using generational selections that will take advantage of insect-mediated cross-pollination, to increase hybrid seed production. Accomplishments 01 Identification of soybean germplasm with supposed cytoplasmic male- sterility (CMS). Additional germplasm was screened in an attempt to identify CMS because all restorers did not give complete restoration. Identification of soybean germplasm with cytoplasmic male-sterility will be useful to produce commercial hybrid soybean seed, enhancing soybean performance for producers. ARS researchers in Ames, Iowa, molecularly mapped all male-sterile, female-sterile mutants in the ARS germplasm collection. The location (clusters on certain chromosomes) of these sterility mutants expands our knowledge about the chromosomal distributi of sterility mutants. The discovery and characterization of CMS and nuclear male sterility provides the genetic material to determine heterosis, higher seed use yield. If successful, this is one step closer to commercial hybrid soybean. There was a very high positive correlation between bee response (PER) and high and low seed-set lines.
Impacts
(N/A)
Publications
- Palmer, R.G., Gai, J., Dalvi, V.A., Suso, M.J. 2011. Male sterility and hybrid seed production. In: Pratap A., Kumar J., editors. Biology and Breeding of Food Legumer. Wallingford, United Kingdom:CAB International. p. 193-2007.
- Palmer, R.G., Shoemaker, R.C., Severin, A.J. 2011. Soybean Genetics. In: J. Miladinovic, M. Mrustic, M. Vidic., editors. Soybean. Becej, Serbia: Sojaprotein. p. 72-136.
- Yang, N., Moon, J., Lee, Y., Lee, S., Kim, H., Hwang, C., Back, K., Palmer, R.G., Jeong, S. 2010. Genetic and sequence analysis of genes controlling natural variation of seed-coat and flower colors in soybean. Journal of Heredity. 101(6):757-768.
- Frasch, R.M., Weigand, C., Perez, P., Palmer, R.G., Sandhu, D. 2011. Molecular mapping of two environmentally sensitive male-sterile mutants in soybean. Journal of Heredity. 102:11-16.
- Perez, P., Cianzio, S., Kara, P.C., Aviles, M., Palmer, R.G. 2011. QTL mapping of whitefly resistance in soybean. Journal of Crop Improvement. 25:134-150.
- Slattery, R.A., Pritzl, S., Krause, K., Trautschold, B., Palmer, R.G., Sandhu, D. 2011. Mapping eight male-sterile, female-sterile soybean mutants. Crop Science. 51:231-236.
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Progress 10/01/09 to 09/30/10
Outputs
Progress Report Objectives (from AD-416) Objective 1: Identify and utilize fertility/sterility mutants in a phenotypic recurrent selection program for insect-mediated cross- pollination to increase hybrid seed production. Objective 2: Identify phenotypes/genotypes that can be characterized and molecularly mapped that contribute to insect-pollinator attraction and reward. Approach (from AD-416) Soybean accessions in the USDA germplasm collection will be crossed with known cytoplasmic restorer lines to identify cytoplasmic male sterile cytoplasms. Sterility mutants (nuclear) obtained via gene tagging from the w4-mutable system will be characterized genetically. Both the cytoplasmic and nuclear sterility mutants will be used in a phenotypic recurrent selection system, with insect-mediated cross-pollination, to increase hybrid seed production. The plant factors that contribute to the increased attraction/reward of the insect pollinators will be identified, characterized, and molecularly mapped. Progress was made on all objectives and their sub-objectives. Progress was made on cytoplasmic male sterility (a type of plant sterility that would greatly enhance hybrid breeding in soybean) in the USDA-ARS soybean germplasm. In 2010, the search for maintainer and restorer soybean germplasm was initiated to preserve our supposed cytoplasmic male-sterile germplasm. Additional fertility/sterility mutants will be molecularly mapped. Plant structural and chemical traits associated with soybean insect-pollinator attraction and reward were identified and characterized at our Nebraska location. For the CRADA, they will identify and characterize traits that contribute to insect-mediated out-crossing, a postdoctoral candidate was identified and will begin work August 2010. Soybean accessions in the USDA germplasm collection were crossed with known cytoplasmic restorer lines to identify cytoplasmic male sterile germplasm. Sterility mutants will be characterized genetically. Cytoplasmic (or extra-nuclear) and nuclear sterility mutants will be used in a plant breeding system using generational selections that will take advantage of insect-mediated cross-pollination, to increase hybrid seed production. Accomplishments 01 Identification of soybean germplasm with supposed cytoplasmic male- sterility (CMS). Identification of soybean germplasm with cytoplasmic ma sterility will be useful to produce hybrid soybean seed commercially. No cytoplasmic male-sterility system has been documented within the USDA-AR soybean germplasm based upon our cross-pollinations. Eight sterility mutants were mapped molecularly in soybean. The location of these sterility mutants expands our knowledge about the chromosomal distributi of sterility mutants. There are clusters of sterility mutants in certain chromosome regions. At present, the significance of this clustering is n known. The discovery and characterization of cytoplasmic male sterility and nuclear male sterility provides the genetic material to evaluate the possibility of commercializing hybrid soybean. Hybrid seed should enhanc agronomic performance and result in increased seed yield, and hopefully increased profits.
Impacts
(N/A)
Publications
- Palmer, R.G., Doyle, J.J. 2009. Anthony H.D. Brown: Conservation Geneticist. Plant Breeding Reviews. 31:1-20.
- Palmer, R.G., Perez, P.T., Ortiz-Perez, E., Maalouf, F., Suso, M.J. 2009. The Role of Crop-Pollinator Relationships in Breeding for Pollinator- Friendly Legumes:From a Breeding Perspective. Euphytica. 170:35-52.
- Cervantes-Martinez, I., Xu, M., Ortiz-Perez, E., Kato, K.K., Horner, H.T., Palmer, R.G. 2009. The Male Sterility Locus ms3 is Present in a Fertility Controlling Gene Cluster in Soybean. Journal of Heredity. 10:565-570.
- Xu, M., Battacharyya, M.K., Palmer, R.G. 2010. Excision of an Active CACTA- Like Transposable Element from DFR2 Causes Variegated Flowers in Soybean [Glycine max (L.) Merr.]. Genetics. 184:53-63.
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Progress 10/01/08 to 09/30/09
Outputs
Progress Report Objectives (from AD-416) Objective 1: Identify and utilize fertility/sterility mutants in a phenotypic recurrent selection program for insect-mediated cross- pollination to increase hybrid seed production. Objective 2: Identify phenotypes/genotypes that can be characterized and molecularly mapped that contribute to insect-pollinator attraction and reward. Approach (from AD-416) Soybean accessions in the USDA germplasm collection will be crossed with known cytoplasmic restorer lines to identify cytoplasmic male sterile cytoplasms. Sterility mutants (nuclear) obtained via gene tagging from the w4-mutable system will be characterized genetically. Both the cytoplasmic and nuclear sterility mutants will be used in a phenotypic recurrent selection system, with insect-mediated cross-pollination, to increase hybrid seed production. The plant factors that contribute to the increased attraction/reward of the insect pollinators will be identified, characterized, and molecularly mapped. Significant Activities that Support Special Target Populations The search for cytoplsmic male sterility in the USDA soybean germplasm was initiated in summer 2008. Hail destroyed approximately 90% of the hybrid pods. These crosses were repeated in summer 2009, plus 200 additional cross-pollinations with plant introductions were made. Advanced populations of fertility/sterility mutants were evaluated by molecular mapping. Fertility/sterility mutants previously identified were added to the allelism tests. The second population for studying insect-pollinator attraction and reward was planted at Texas and Nebraska. A CRADA is being finalized on the identification, characterization, and molecular mapping of insect-pollinator attraction traits in soybean.
Impacts
(N/A)
Publications
- Healy, R.A., Palmer, R.G., Horner, H.T. 2009. Multicellular Secretory Trichome Development on Soybean and Related Glycine Gynoecia. International Journal of Plant Science. 170(4):444-456.
- Perez, P.T., Cianzio, S.R., Palmer, R.G. 2009. Evaluation of Soybean [Glycine max (L.) Merr.] F1 Hybrids. Journal of Crop Improvement. 23:1-18.
- Perez, P.T., Cianzio, S.R., Palmer, R.G. 2009. Heterotic Patterns of Soybean Lines from 3-Way, 4-Way and 5-way Crosses, and Backcross Populations. Journal of Crop Production. 23:95-118.
- Palmer, R.G., Min, X. 2008. Positioning Three Qualitative Trait Loci on Soybean Molecular Linkage Group E. Journal of Heredity. 99:674-678.
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Progress 10/01/07 to 09/30/08
Outputs
Progress Report Objectives (from AD-416) Objective 1: Identify and utilize fertility/sterility mutants in a phenotypic recurrent selection program for insect-mediated cross- pollination to increase hybrid seed production. Objective 2: Identify phenotypes/genotypes that can be characterized and molecularly mapped that contribute to insect-pollinator attraction and reward. Approach (from AD-416) Soybean accessions in the USDA germplasm collection will be crossed with known cytoplasmic restorer lines to identify cytoplasmic male sterile cytoplasms. Sterility mutants (nuclear) obtained via gene tagging from the w4-mutable system will be characterized genetically. Both the cytoplasmic and nuclear sterility mutants will be used in a phenotypic recurrent selection system, with insect-mediated cross-pollination, to increase hybrid seed production. The plant factors that contribute to the increased attraction/reward of the insect pollinators will be identified, characterized, and molecularly mapped. Significant Activities that Support Special Target Populations The search for cytoplasmic male sterility in the USDA soybean germplasm was initiated and manual cross-pollinations were made. Newly identified male-sterile mutants were cross-pollinated to test for allelism with mutants in the Genetic Type Collection. Plant-progeny rows were evaluated and selection will be made for Population 2 to molecularly map the insect-pollinator attraction and reward traits. Plant samples for nectary starch have been analyzed and data processed for publication. This project 3625-21000-054-00D, Identification of Plant Genetic Mechanisms that Influence Insect-Pollinator Preference fits within NP301 Plant Genetic Resources, Genomics, and Genetics Improvement, Component 3 because germplasm with increased pollinator attraction are being developed.
Impacts
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Publications
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