Location: Soybean and Nitrogen Fixation Research
Project Number: 6070-21220-069-121-A
Project Type: Cooperative Agreement
Start Date: Oct 1, 2021
End Date: Sep 30, 2022
1. Evaluate existing low oil, high protein lines, which are already under development for seed yield and stability across environments from maturity group 00-VIII. Yield trials will be conducted in MN, IL and NC in 2022. 2. Evaluate very low oil (<16%), high protein (>45%) lines from GRIN from maturity groups 00-VIII for use in developing new breeding populations. 3. Make crosses to allow identification of previously unidentified QTLs for low oil and improved nutritional value. The Danbaekkong protein allele on chromosome 20 is the most notable source for increasing seed protein in soybean. 4. Develop low oil, high protein germplasm with improved nutritional value. Nutritional value will be based primarily on amino acid and fatty acid composition, to help meet industry demands.
Five low oil (<18%), high protein (>40%), and high meal protein (>55%) lines, five high oil and low protein lines, a known heat tolerant line, and a known heat susceptible line will be tested for drought and heat tolerance and seed composition (oil, protein, and fatty acid composition)under these stresses. Two sets of plants will be grown under controlled environmental conditions- one set for drought stress experiment and the other for heat stress experiment. All plants will be grown under optimal temperature (30/20°C) and water conditions until R5 growth stage (beginning seed). Thereafter, in each set, half of the plants will be subjected to the respective stress (drought or heat) for three weeks and the other will be maintained under optimal conditions. Drought stress will be imposed following the standard procedure developed by Sinclair and Ludlow (1986) and Ray and Sinclair (1998). Heat stress (38/28°C) will be imposed using a growth chamber. Stress response of plants will be quantified based on photosynthesis, chlorophyll fluorescence, chlorophyll index, leaf temperature, and seed yield. The seeds will be harvested at maturity and used to estimate oil and protein content and fatty acid profiling. Total oil and protein contents will be measured by NIR spectrometry. After in-situ transesterification, fatty acid composition in seeds will be measured via gas chromatography (GC) with flame ionization detection (FID).