Novel Gene Pyramiding to Combat Rusts in Global Wheat Varieties against Prevalent Virulence: A Review

Epidemics caused by leaf, stripe and stem rust have significant threat to agro-ecosystems and worldwide food security. Semi-dwarf wheat varieties with major gene resistance could not continue for longer period due to emergence of new rust races. However, genotypes such as Inqilab-91, Bluebird, Kenya Plume and Hope developed in early part of green revolution retained their resistance for longer period due to presence of non-specific rust resistance genes. Until now, 187 rust resistance genes (80 leaf rust, 49 stripe rust, 58 stem rust) have been described from different wheat and durum cultivars and related local species using different molecular approaches. This review provides a detailed discussion of the different aspects for controlling three rust diseases caused by P. recondita Rob. exdesm f. sp. tritici , P. striiformis West. f. sp. tritici, P. graminis Pers. f. sp. tritici and the importance of race specific and non-specific rust resistance genes in in global wheat varieties. This knowledge will help as basis for plant pathologist, plant breeders and genetics to develop non-specific rust resistant wheat varieties through gene pyramiding or marker assisted breeding.