Polymorphism Analysis of Seed Storage Proteins in Foxtail Millet ( Setaria italica L. Beauv.) with A-PAGE

Abstract

The polymorphism of water-soluble protein, salt-soluble protein, acid-soluble protein and prolamin was analyzed by A-PAGE in 24 foxtail millet varieties from different ecological zones. The results revealed that the banding patterns of the water-soluble protein in different millet varieties were similar to those of the acid-soluble protein. There existed over twenty bands of the salt-soluble protein in each millet variety, and only four varieties contained polymorphic bands, showing that bands of the water-soluble protein, the salt-soluble protein and the acid-soluble protein obtained by A-PAGE are not available to use in millet varieties identification. There existed a certain degree of heterogeneity in millet prolamin bands. Seven to ten prolamin bands appeared in tested varieties, five of which were the common ones, two to five of which were polymorphic, so prolamin patterns of millet varieties can be used in variety identification and evaluation. The results showed that there was less variance for proteins in tested millet varieties from different ecological zones compared with other major cereal crops like wheat and corn, which implies that only a limited heterogeneity in the genetic background of millet varieties. Therefore, it is very important to enrich the genetic basis of millet genetic stocks to develop elite varieties.