Meha Sharma2017-02-132017-02-132014http://krishikosh.egranth.ac.in/handle/1/5810000674Powdery mildew, caused by Blumeria graminis f.sp. tritici is a major foliar disease of wheat worldwide.Present investigation was undertaken for generation of linkage map in Synthetic43 X WH542 RIL population and mapping of powdery mildew resistance gene using this linkage map. A synthetic wheat, Synthetic 43, derived from CIMMYT is found to be resistant to rust and powdery mildew(PM) pathogens, besides having several agronomically important characters. A RIL population was generated by crossing Synthetic 43 with cultivated wheat variety WH542 through single seed descent method. Inheritance studies in RIL population revealed monogenic inheritance of powdery mildew resistance both at seedling and adult plant stage. This gene was temporarily designated as PmT. For generating linkage map maximum of 80 polymorphic SSR markers have been selected from D genome while 34 were selected from A and B genome corresponding to low polymorphic regions of D genome.These 114 SSR subjected to linkage analysis using MAPDISTO (1.7.6.5) software at LOD 2.5 and only 52 markers were mapped generating a linkage map of length 693.5cM with 13 linkage groups. These linkage groups were aligned with already known consensus map of wheat and 7 homeologous groups were generated. The size of these seven homeologous groups varied from 54.4cM (homeologous group 2) to 153.9cM (homeologous group 5). The marker order was generally collinear with the already published bread wheat consensus map with only 12 marker showing discrepancies in order and five SSRs mapped onto a different homeologous group. Out of 52 mapped SSRs 11 showed segregation distortion from expected ratio of 1:1.Using this linkage map, PmT gene was mapped on homeologous group 7 at a distance of 11.6cM distal to SSR Xwmc150. Xwmc150 has been mapped on the long arm on of chromosome 7D according to wheat consensus mapensowing, intercropping, wheats, tillage equipment, seed drilling, crops, mustard, fertilizers, land resources, chickpeasThesis