Comparative Protein Fraction Analysis for Commercial Hybrid Seed Purity Testing in Cotton (Gossypium Hirsutum L.)

An experiment was designed to find out the best suited seed protein fraction for identifying the genetic contaminants in seeds of two cotton hybrids viz., CSHH 198 and CSHH 238 where its morphological and genetic differences are meager. The electrophoretic comparison of albumin, globulin, and prolamin seed protein fractions revealed that both albumin and globulin fractions are able to differentiate the hybrids from its male and female parents. The analysis of seed proteins of two cotton hybrid revealed that, albumin fraction produced six different fingerprints with highest discrimination ability than globulin fraction (three). Due to this, albumin fraction showed the added advantage in assessment of genetic purity of CSHH 198 hybrid seed lot that are contaminated with its own parental (selfed female) seeds as well as CSHH 238 cotton hybrid. In contrast, globulin fraction can only be used for identification of off type contaminations due to its own parental seeds and prolamin was unable to differentiate any contaminant. Thus, water soluble albumin protein fraction can be used to differentiate the CSHH 198 and CSHH 238 cotton hybrids and their parental line for both genetic and hybrid purity testing.