Biochemical Basis and Molecular Genetics of Processing and Nutritional Quality Traits of Wheat

Wheat is unique in the sense that large numbers of end-use products such as chapati, bread, biscuits, noodles and pasta products are made from it. This is possible because of visco-elastic property imparted to the dough by its gluten proteins. Grain texture, gluten constituents and starch composition in the endosperm are major determinants of end-product quality. Each end-use product has its own specific requirements. Therefore, to expedite the breeding programme for the development of product-specific varieties, understanding the grain components at biochemical/molecular level and their relationship with quality, is needed. Impressive advances have been made in understanding the subunit composition of glutenins, gliadins and starch at biochemical and molecular levels. Molecular markers for these components have been identified, and are being used in breeding for the improvement of wheat quality. Wheat is also deficient of certain micronutrients such as Fe and Zn and lysine content. There is increasing concern globally for the improvement of the nutritional quality of wheat for micronutrient content, and protein and starch quality. Transgenic approach will be helpful in manipulating metabolic pathways for enhancing micronutrient bioavailability and increased lysine content. In this review, information on recent developments that have taken place in understanding the biochemical basis and molecular genetics of processing and nutritional quality of wheat grain and its future implications, has been provided.