Analyses of acid-PAGE gliadin pattern of Indian wheats (Triticum aestivum L.) representing different environments and periods

Acid-PAGE analysis of gliadins from 159 Indian wheat (Triticum aestivum L.) cultivars developed during the last five decades was accomplished to identify gliadin band patterns as well as the extent of genetic diversity. Extensive polymorphism [genetic diversity index (H) = 0.875] in gliadin pattern was observed in the cultivars studied. A total of 147 band patterns were identified, of which 45 different mobility bands were in the region of omega gliadins, 42 in the region of gamma gliadins, 30 in the region of beta, and 29 in the region of alpha gliadins. Zone-wise genetic diversity index was highest in North Western Plains Zone (H = 0.904) followed by North Eastern Plains Zone (H = 0.878), Central Zone (H = 0.864), Peninsular Zone (H = 0.844), and Northern Hills Zone (H = 0.836). The alpha gliadin pattern 1, 8, 11, and 20; beta gliadin pattern 21; gamma gliadin pattern 15 and 20; and omega gliadin pattern 4, 18, and 38 were specific to cultivars of Northern Zones and alpha gliadin 20 and beta gliadin 22 to Central and Peninsular Zones. Period-wise highest mean genetic diversity (H = 0.915) was observed in cultivars identified during 1971 through 1980 and lowest (H = 0.868) in cultivars developed after 1990. The reduction in genetic diversity during 1990 onward might be because of enhanced use of 1BL.1RS translocation. This information can be used in breeding programs to maintain genetic diversity within Indian wheat germplasm.