Utilization of wheat relatives to improve wheat breeding for rust resistance

Wheat is a major food source in a range of countries, thereby largely contributing to food security in vast areas worldwide. Stripe rust (Puccinia striiformis f. sp. tritici), stem rust (P. graminis f. sp. tritici) and leaf rust (P. triticina erikson) are three major wheat diseases which cause yield and quality loss of wheat. Wild relatives of wheat are dynamic resources for unique traits, not present in cultivated wheat. Different breeding strategies have been used for introgression of alien genes into wheat, to transfer genes contributing tolerance/resistance against biotic and abiotic stresses. The secondary and tertiary gene pools are playing a pivotal role in developing wheat-alien introgression lines. In this paper, the importance of wheat, types of rust, rust resistance types, wheat gene pools, molecular methods used for gene deployment and utilization of alien germplasm are discussed.