Development of tryptophan rich maize lines through simple sequence repeat marker aided introgression of opaque2 trait

  Maize is the main staple food of world but it nutritional deficient due to scarcity two essential amino acids viz., lysine and tryptophan. Under this study, opaque2 gene from QPM donor (CML-169) was transferred into normal maize (BAJIM-08-26) through marker aided backcross breeding method. The specific SSR (phi057) used for foreground selection in BC1F1 BC2F1 generations. heterozygous offspring were self-pollinated produce BC2F2 generation. Further plants on basis 25% opaqueness selected selfed develop BC2F3 BC2F4 progenies. background using a series markers showed 97% recovery recurrent parent genome backcrossed Tryptophan content total protein endosperm progenies  found be ranged 0.75 0.93% 7.0 9.6 %, respectively. As an outcome, three promising MAS derived lines B76-22-2, B70-5-8 B42-3-1 developed that high percentage tryptophan, grain yield genome. The  worldwide problem malnutrition could improved by adopting molecular approach development nutritionally rich over maize. Keywords: Marker assisted backcrossing, opaque2, tryptophan content, markers,