Soybean Composition Studies

Researchers at the University of Minnesota have been investigating the relationships between cell wall polysaccharides, protein and oil content in soybeans. The studies targeted genes that control cell wall polysaccharides. The research team reported negative correlations of protein with oil; and the sum of oil and protein with most of the monosaccharides, pectin and cell wall polysaccharides within the recombinant inbred lines evaluated. These results indicated that reducing seed cell wall polysaccharides (fructose, galactose, arabinose, pectin) might increase protein levels of soybeans. The researchers identified several loci associated with genes that control cell wall polysaccharides; these results can be helpful to soybean breeders and biotechnicians interested in improving the protein content of soybeans.

Stombaugh, S.K. 2004. Quantitative traits loci associated with cell wall polysaccharides in soybean seed. Crop Sci. 44(6): 2101-2106.

In a study to improve the digestibility of phosphorus in soybeans, research was initiated to evaluate the impact of a low phytate trait on the agronomic and seed traits of soybean lines with a reduced palmitic acid levels. Crosses were made between a low phytase germplasm and a line with reduced palmitate levels. Twenty BC1F2-derived liens with low phytate and reduced palmitate were grown in three environments in Iowa. Results indicated the low phytate lines had 22.3 % lower seedling emergence compared to the normal phytate lines. The lower seedling emergence did not significantly affect seed yields due probably to commentary plant growth. They also found the total stearic and palmitic acid levels of the low phytate lines were significantly greater than the reduced palmitate parent. The researchers concluded that development of low phytate varieties with low levels of saturated fatty acids would be difficult.

Hulke, B.S. and co-workers. 2004. Agronomic and seed characteristics of soybean with reduced phytate and palmitate. Crop Sci. 44(6): 2027-2031.