Family-Based Linkage Mapping of Preharvest Sprouting Resistance QTL In Spring Wheat.

Conventional QTL mapping approaches are based on analysis of different types of bi-parental populations. Different limitations associated with this methodology are; time required to developed specific mapping populations, markers linked to QTL of interest are not immediately available for use in breeding program, and rarely develop new cultivars. Plant breeders had suggested use of breeding population for simultaneous QTL mapping, marker validation and cultivar release. Family-pedigree based QTL mapping technique has been used successfully in human and animals. Preharvest sprouting (PHS) defined as condition of in-spike germination of physiologically mature seeds, has resulted yield loss as well as degradation of grain quality. This will lead to economic losses to farmers and processing industry. Developments of PHS-resistant cultivars are the most effective way of addressing the problem. The objective of this study is to use family- based QTL mapping technique to determine PHS QTL in spring wheat. Mapping populations are developed through three way or four way crosses among a number of spring wheat genotypes. Both, variance component and pedigree-wide regression approach will be applied to map PHS QTL. This study will also validate applicability of the approach in quality traits such as PHS.