Location: Crop Genetics Research
Project Number: 6066-21220-016-007-R
Project Type: Reimbursable Cooperative Agreement
Start Date: Oct 1, 2022
End Date: Sep 30, 2023
Objective:
To develop soybean cultivars with improved tolerance to mature seed damage.
Approach:
Growing early-maturing varieties (maturity groups III-IV) from the standard gene pool in the mid-south US often produces damaged seeds that are price-discounted by buyers at grain elevators. Losses can be severe enough to significantly reduce profit margins. In this project, improved experimental breeding lines with significantly lower mature seed damage in the early soybean production system will be developed, tested, and transferred by breeding material transfer agreements to soybean breeders who will use them to develop damage-tolerant cultivars for US producers. To accomplish this, improved heat tolerant soybean lines developed previously by ARS will be crossed with mold tolerant soybean accessions (plant introductions from the USDA Germplasm Collection) to develop segregating populations. Also soybean breeding lines that have been shown to have low mature seed damage in our nursery will be crossed to elite lines to develop segregating populations. Selection will be practiced on these breeding populations, where heat tolerance, mold tolerance, and high yield will be selected. Advanced homogeneous lines will be screened in replicated field trials grown under over-head sprinklers operated twice daily, with Phomopsis longicolla inoculation at R5, and delayed harvest 14 days after maturity. Certified Federal Grain Inspection Service graders will rate seed for each line for mature seed damage. The best of the experimental lines that have significantly less seed damage than cultivar checks will be transferred and/or released for cultivar development.