Document Type

Thesis - University Access Only

Award Date


Degree Name

Master of Science (MS)

Department / School



Improving soybean protein concentration without lowering oil and seed yield is difficult. Relative levels of protein, oil, and yield in the parents may influence the frequency of progenies with acceptable levels of all three traits. This study was conducted to evaluate the dynamics of five soybean populations with various parental combinations of protein, seed yield, and oil. Replicated hill plots of F3:4 and F 4:s populations from five crosses were planted in a group balanced block design, with parental lines as checks in 1999 and 2000. Protein and oil analyses were conducted by NIRS. Mean protein concentrations for crosses of medium yield-high protein x low yield-high protein and low yield-high protein x low yield-high protein were similar, and greater than crosses of high yield-normal protein x low yield-high protein. Protein concentrations among all crosses ranged from 501 to 376 g kg·1. Correlations between protein and seed yield ranged from 0.02 to 0.24 in FJ:4, and -0.06 to -0.33 in F 4:5 lines; and were mostly nonsignificant. All correlations between protein and oil were negative and highly significant ranging from -0.45 to -0.96. Broad sense heritability estimates for protein concentration on an entry mean basis ranged from 0.30 ± 0.38 to 0.88 ± 0.03. Medium yield-high protein x low yield-high protein, and low yield-high protein x low yield-high protein crosses showed transgressive segregation for protein concentrations greater than the high protein parent in both F3:4 and F 4:5 generations. This parent may be useful for protein improvement in the future. Even among these five populations of two-parent crosses, It was possible to select high protein lines

Library of Congress Subject Headings

Soybean -- Varieties
Soy proteins
Soybean -- Seeds
Soy oil



Number of Pages



South Dakota State University