Abstract:We used close linkage molecular markers of resistance genes Lr46/Yr29/Pm39,Sr2/Yr30 and Lr68 to analysis the genetic characteristics of the resistance genes in the BC1F1 and F2 descendant populations.The BC1F1 and F2 descendant populations both came from ‘RL6077’ and ‘Xinong 979’.Combined with the main agronomic traits,we could deeply comprehend the gene heredity rule of wheat disease resistance genes as well as the correlation with agronomic traits.We also evaluated the background response rates of 92 plants in the BC1F1 population who have three kinds of resistance genes at the same time.The result showed that:(1)In the F2 population the transfer rate of gene Lr68 (65.41%) is lower than theory,but the transfer rate of Lr46/Yr29/Pm39 (75.83%) and Sr2/Yr30 (74.53%) is consistent with the theoretical,respectively.In the BC1F1 population,the transfer rate of gene Lr68 (44.27%) transferred lower than theory,while the transfer rate of Lr46/ Yr29/Pm39 (56.64%) and Sr2/Yr30 (55.11%) gene delivered higher than theory,respectively.(2)All these three kinds of resistance genes have extremely significant positive correlation with the plant height,spike length,spike-stalk and spike-internode.The Lr68 gene and Sr2/Yr30 gene have significant or extremely significant positive correlation with the spike grain number.The Lr46/Yr29/Pm39 gene has significantly negative correlation with the thousand kernel weight and significantly positive correlation with the ear number per plant.(3)In the evaluate of the background response rates of plants in the BC1F1 population which have Lr46/Yr29/Pm39,Sr2/Yr30 and Lr68 genes.Meanwhile,we can find that the biggest response rate of recurrent parent ‘Xinong 979’ was up to 91.67%.There were three plants whose response rates exceed 90% and they take 0.46% of the BC1F1 population.This study provided an important theoretical reference to using the excellent genetic resources of ‘RL6077’.It also has important significance to create a variety of new disease-resistant wheat germplasm.
