Soybean meal has value due to its protein and amino acid levels. Short-chained carbohydrates, raffinose and stachyose are poorly used in some species and are considered to have a negative effect in the nutritional value of soybean meal in livestock rations. Research has been conducted to determine the relationship between protein, oligosaccharides and sulfur in soybean populations that vary widely in protein content. Soybean lines varying in protein levels 42.3 to 46.8% were grown in three environments. Seed yield, protein, oil, oligosaccharides and sulfur levels were determined for each variety in each environment. These results demonstrated that the soybean varieties and environments varied significantly for each of the traits measured. Negative correlations between protein and oil (b= -1.5601), total carbohydrate (b= -0.171) and sucrose (b= -0.151) were observed. The sulfur to nitrogen ration was constant across protein levels. These results indicate that soybean breeders can improve the nutritional value of soybeans by increasing protein levels and by reducing the carbohydrate levels in soybean germplasm lines. The constant ratio of sulfur to nitrogen levels indicates that the sulfur containing amino acids are increased as protein levels are improved.
Wilcox, J.R. and R.M. Shibles; 2001. Interrelationships among seed quality attributes in soybean; Crop Sci. 41(1):11-14.