QTL Mapping For Sitodiplosis Mosellana Resistance In Wheat Cultivar Jimai24

The Sitodiplosis mosellana Gehin is a destructive vermin of wheat, which makes wheat yield lose and quality low throughout the world. Breeding and popularizing resistance cultivars has been proved the most effective, economical and environmental safe method to suppress the midge broad-spectrum Sitodiplosis mosellana resistance. Therefore the exploitation of insect-resistant genes, including its marking, location and molecular-marker aided selection, would benefit for the breeding effective of Sitodiplosis mosellana resistant cultivars. In this study, using SSR technic, The QTLs for the resistant of Sitodiplosis mosellana of wheat varity jimai24 were detected through interval mapping. The results are showed just as follows:1. QTL analysis with the losing ratio and the result of the screening 328 pairs of wheat microsatellite primers located on the 7B to the insect-resistant gene of Sitodiplosis mosellana which round Wms400, and identificated five markers, including Xgwm537, Wms400, Xgwm46, Xbarc176 and Xgwm3022. Five markers located on the 7B chromosome to the jimai24 insect-resistant gene of Sitodiplosis mosellana, which indicated the dominating gene distributed on 7B chromosome. The gene was denominated Sm2 transitorily.3. Based on interval mapping, identified one insect-resistant gene of Sitodiplosis mosellana QTLs of jimai24-Sm2 whose dominance effect was -19.93, additive effect was 17.01, and likelihood ratio stastic was 83.6 explain 24% of the Sitodiplosis moseUana Resistance. Two markers Wms400 and Xgwm46 linked to this gene with the genetic distance of 5.2 cM and 20.2 cM was found. Wms400 was regarded as an assistant selecting marker for the gene.