Prolamins and Glutelins as protein markers to distinguish normal lines from QPM germplasm

Abstract

Maize protein quality is poor due to high content of zein protein lacking essential amino acids: lysine and tryptophan. Opaque2 mutants were discovered having high lysine, tryptophan due to reduction zeins with pleotropic effects such as soft and chalky kernel. Quality protein maize (QPM) were developed with high protein quality and vitreous kernel texture. Present study was planned to establish protein markers to distinguish normal maize from QPM. Kernels were harvested from normal and QPM lines for estimation of protein fractions from extracted endosperm. Results revealed that prolamin and glutelin are the two major fractions affected by opaque-2 mutation. Prolamin is highest in normal (44.9%) and least in QPM (8.94%) whereas, glutelin is more in QPM (32.9%) than normal lines (17.6%). Hence out of all protein fractions, prolamin and glutelin show maximum variation, so can be used as precise and cost effective protein markers to differentiate normal lines from QPM.