Location: Crop Production and Pest Control Research
Project Number: 5020-21220-009-000-D
Project Type: In-House Appropriated
Start Date: May 9, 2023
End Date: May 8, 2028
Objective:
Objective 1: Conduct research to identify genetic loci involved in soybean seed protein and oil accumulation, characterize resource partitioning of the new soybean genotypes, and work with breeders to develop new germplasm incorporating genes for improved protein and oil traits.
Goal 1.A: Map genetic loci involved in soybean seed protein and oil accumulation.
Goal 1.B: Work with breeders to evaluate and incorporate new meal and oil traits.
Objective 2: Conduct research to elucidate pathogen biology, fungicide resistance, and virulence of Frogeye Leaf Spot disease, and identify novel host resistance to this threat to soybean production in the North Central region.
Hypothesis 2.A: Frogeye leaf spot in the northcentral states is caused by distinct clonal lineages consisting of both mating types and wide-spread-QoI resistance.
Hypothesis 2.B: C. sojina populations have high virulence diversity.
Hypothesis 2.C: Low-level sexual recombination occurs in C. sojina.
Objective 3: Conduct field and greenhouse research evaluations and statistical analyses to collect breeding-related data, and report results on testing of public sector soybean breeding lines evaluated in the Uniform Soybean Tests – Northern Region.
Goal 3: Evaluate advanced public breeding lines for agronomic performance, disease resistance and quality traits throughout the northcentral U.S. and Canada.
Approach:
Objective 1:
Genes involved in soybean seed protein and oil accumulation will be isolated through phenotypic screening of seed composition traits. Mapping populations will be developed to isolate and characterize genes conferring improved composition phenotypes. Environmental and developmental characteristics will be examined in protein:oil mutants to further understand the control of resource partitioning in the seed. New and existing genes will be combined and evaluated for their utility to provide soybean breeders with new composition traits for current and future needs.
Objective 2:
Cercospora sojina isolates will be collected from soybean fields in Indiana and other states. The isolates will be examined for resistance to QoI fungicides by amplifying and sequencing their mitochondrial cytochrome b gene. Their mating types will be determined by amplifying Mat1-1 and Mat1-2 genes using gene-specific primers. The pathogen population will be genotyped using a panel of single nucleotide polymorphism markers. Isolates representing different genotypes will be used to inoculate a set of 14 soybean differentials to determine their virulence. Isolates with different mating type genes will be used to co-inoculate soybean. Pathogen will be re-isolated from plant tissue and genotyped to determine whether sexual recombination occurred.
Objective 3:
Public soybean breeders submit their soybean breeding lines for evaluation of agronomic performance, disease resistance and quality traits. Entries are separated by maturity group and assigned to either the ‘Preliminary Tests’ or the ‘Uniform Tests’. Seeds of each entry, along with those of the standard reference varieties, are packaged and distributed to collaborators throughout the U.S. and Canada for evaluation. In addition, entries will be evaluated at multiple locations in Indiana. Harvested seeds will also be tested for quality traits. Collaborators submit performance data from their locations to ARS after harvest. This data is compiled and analyzed by this research group following established protocols. The results will be published in an annual report book and online.
