Location: Plant Genetics Research
Project Number: 5070-21000-044-029-A
Project Type: Cooperative Agreement
Start Date: Oct 1, 2023
End Date: Sep 30, 2024
Objective:
Drought is the single greatest cause of soybean yield loss, and the incidence and severity of drought is expected to increase in coming decades. A more sustainable solution is to identify and deploy adapted soybean cultivars that are more tolerant of water limitation.
Breeding efforts generally focus on repeated crossing between elite lines – essentially failing to take advantage of the vast genetic diversity in the soybean USDA-GRIN germplasm collection. We have taken key steps to leverage this diversity, via multi-location and drought stress genetic experiments that identified maturity group (MG) 4 Plant Introductions (PIs) with positive drought–associated traits: lower Canopy Wilting (CW), higher Water Use Efficiency (WUE), higher Nitrogen Derived From the Atmosphere (NDFA, as a measure of nitrogen fixation), and lower Canopy Temperatures (CT). Our experiments leveraged prior investment by the USB in obtaining marker data for >19,000 accessions in the USDA germplasm collection.
These efforts have paid off, and we have already reported several hundred genetic marker associations with our drought tolerance traits. Our efforts will reach fruition during the lifetime of this grant; germplasm releases will serve to broaden the genetic base and deploy drought alleles in improved soybean genotypes that will provide valuable tools to commercial and public breeders and producers to meet the substantial challenges of increased incidence and severity of drought stress.
Approach:
Our previous research with USDA-GRIN lines with favorable drought associated traits crossed to elite public parental line resulted in creation of populations containing the best possible alleles for multiple drought-associated traits. We also intercrossed among our populations to generate Multi-parent Advanced Generation InterCross (MAGIC) genetic mapping populations specific for drought traits. We intend to identify and release soybean germplasm which will serve to broaden the genetic base and deploy drought alleles in improved soybean genotypes, as well as use our new materials for genetic mapping for traits associated with drought tolerance.
We have three main activities that will be used to meet these objectives:
1. Confirm drought-tolerance traits and seed yield for the most promising biparental selections (G1F4:5).
2. Test seed yield and tolerance using selected (G4F5:6)MAGIC lines.
3. Perform a multi-location study with a large, previously genotyped MAGIC population for four drought-associated traits.
MWA-ARS location in Missouri personnel will have primary responsibility for overall project coordination and reports, for collecting and processing all genomic/genotypic data and for coordinating winter nursery advancement of all prospective germplasm. MWA-ARS and Cooperator personnel will also be primarily responsible for overseeing data analysis. Physiological and yield data will be collected by project partners with the required physiological/breeding expertise at remote field locations (Missouri, Arkansas).
Project partners have already and will continue to substantially share data collected and germplasm generated by this project. MWA-ARS personnel and Cooperators carried out crossing efforts collaboratively and collectively in previous years of the project.
