chapter  12
20 Pages

Molecular markers for wheat Improvement: Tool for precision rust resistance breeding

WithSubodh Kumar, Subhash C. Bhardwaj, Om P. Gangwar, Pramod Prasad, Hanif Khan, Siddanna Savadi

342Wheat rusts are among the major biotic impediments in our efforts to consolidate the genetic gains. The management of wheat rusts through host resistance is the safest and environmental friendly approach. Incorporation of new and diverse sources of rust resistance is a continuous pursuit. So efforts are always going on to incorporate of both major and minor genes to develop durable rust resistant wheat varieties. It is necessary to have tools to determine the resistant genotypes of crop varieties and their confirmation into the target genotype. The molecular marker techniques are sound tools, which enhance efficiency and effectiveness of the genetic analysis of resistance, and the selection of combinations of resistance genes in a crop improvement program. DNA-based molecular markers have acted as versatile tools and found their way into various fields like taxonomy, plant breeding, and genetic engineering. Robust and tightly linked markers can be used to select indirectly for the desirable allele and this represents the simplest form of marker-assisted selection (MAS). MAS not only helps in compressing the population but is also a precise tool to have desirable genotypes through foreground and background selections. Markers can also be used for dissecting polygenic traits into their Mendelian components or quantitative trait loci (QTL). Several types of molecular markers, both Non-polymerase chain reaction (PCR) (restriction fragment length polymorphism) and PCR based (randomly amplified polymorphic DNA marker, amplified fragment length polymorphism, microsatellites etc.) have been utilized in wheat improvement during the recent years and efforts are on to have better and fine type of markers taking the advantage of available genome sequence of wheat.