ARS | Publication request: Genetic analysis of populations derived from matings of southern and northern soybean cultivars

Submitted to: Crop Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: June 22, 2011
Publication Date: November 1, 2011
Citation: Feng, L., Burton, J.W., Carter Jr, T.E., Miranda, L.M., St. Martin, S., Brownie, C. 2011. Genetic analysis of populations derived from matings of southern and northern soybean cultivars. Crop Science. 51:2479-2488.

Interpretive Summary: Breeding progress can only be achieved by maintaining genetic diversity in breeding populations. However, using exotic germplasm that is un-adapted to the U.S. growing conditions is often challenging and requires several generation of backcrossing and selection. One approach to circumvent this problem in the south is the use of northern germplasm. Recent studies have shown that southern and northern U.S. soybean cultivars belong to two very distinct gene pools based on pedigree and molecular marker analysis. The purpose of this research was to evaluate the usefulness of matings between southern and northern cultivars for applied soybean breeding. Nine populations were derived from matings of two southern soybean cultivars, Johnston and Stonewall, with three ancestral A.K. (Harrow), Lincoln, Mandarin and three improved Flyer, Sibley, Zane northern cultivars. Two hundred lines from these populations were evaluated in field trials. Significant genetic variation was observed for all the traits evaluated including yield, maturity, height, seed quality, seed weight, protein, oil, and fatty acid composition. Some of the breeding lines that were developed had yield comparable to modern southern cultivars. Results suggested that improved northern cultivars would be useful parents for practical breeding programs in the south.

Technical Abstract: Genetic diversity is one of the important considerations in selecting parents for applied cultivar development in soybean [Glycine max (L.) Merr.]. Recent studies have shown that southern and northern U.S. soybean cultivars belong to two very distinct gene pools based on pedigree and molecular marker analysis. A study was conducted to evaluate the potential of matings between southern and northern cultivars for applied soybean breeding. Nine populations were derived from matings of two southern soybean cultivars, Johnston and Stonewall, with three ancestral A.K. (Harrow), Lincoln, Mandarin and three improved Flyer, Sibley, Zane northern cultivars. Field trials showed statistically significant differences among and within crosses for mean yield, maturity, height, seed quality, seed weight, protein, oil, and fatty acid composition. There were significant differences in means and genetic variances among populations derived from male (northern) cultivars for mean yield, and all other traits recorded. Results suggested that improved northern cultivars would be useful parents for practical breeding programs in the south. Populations derived from Flyer produced the highest mean yields. A significant correlation (r = -0.82) between coefficient of parentage (CP) value and genetic variance estimate for cross yield may indicate that CP is a useful measurement in predicting genetic variation among matings of inbred soybean cultivars.