Consumers looking for healthy foods may someday be buying vegetable soybeans at their local produce departments. Harvested at the immature seed stage, vegetable soybeans could be eaten as a vegetable much like green peas or lima beans. Harvested dry, they could be used for soyfood products.
Vegetable soybeans contain isoflavones that are desirable for their biological and biochemical activity. Researchers at Virginia State University and South Dakota State University have been studying the heritability and variety-environment interactions for isoflavone concentrations.
To date, the research indicates that varieties respond differently from one growing season to another. So multiyear testing is required to make unbiased variety selection. The researchers have found significant maturity group effects. Varieties from an early maturity group exhibited higher values than those from later maturity groups.
Similar work in Brazil at the National Soybean Research Center of Embrapa has shown there is significant genetic variability for isoflavone concentration among Brazilian varieties.
Environmental effects on isoflavone concentrations have also been observed. Brazilian scientists plan to test the possibility of choosing location to manipulate the concentration of these compounds in soybean varieties.
(Tadesse Mebrahtu and Ali Mohamed, Virginia State University; C.Y. Wang, South Dakota State University; M.C. Carrao-Panizzi, et al, Brazil's National Soybean Research Center)