Molecular Mapping Of Leaf Rust Resistance Gene In Wheat Henong 5290 At Adult Stage And Molecular Mark Assisted Selectionfor Pyramiding Leaf Rust Resistance Accessions

Wheat leaf rust caused by Puccinia triticina is one important worldwide diseases, it can result in severely reduced of global wheat. In recent years, climate conditions become more appropriate occurrence and spread of wheat leaf rust for global warming, wheat leaf rust occurrence is growing and the control of the disease has become essential. The most cost-effective method is utilization of resistant varieties. But most of the genes which have been officially named confered physiological specifically resistance to wheat leaf rust. The wheat cultivars always lost their resistance to leaf rust when virulent races emerge or increase. Only Lr9, Lr19, Lr24, Lr34, Lr38, Lr42, Lr43 and Lr46 etc provied strong resistance to races of P. triticina in China till now. However, these resistance genes are difficult to sustained control the spread of the wheat leaf rust and easy to be overcomed by the new leaf rust races. This condition requires scientists constantly discovering new resistance genes and developing new high yield disease-resistant varieties.Henong 5290 is a new variety of wheat developed by Agricultural University of Hebei. The preliminary research from our lab showed that 5290 contributed higher disease resistance level to wheat leaf rust. And genetic analysis of leaf rust resistance showed that the resistance of Henong 5290 was controlled by a dominant resistance gene which was different from the known wheat leaf rust resistance genes. In this study, resistant parent Henong 5290, susceptible parent Zhengzhou5389 and their F3 families were employed, and BSA and SSR technique were used to maping the adult leaf rust resistance gene in Henong 5290. Meanwhile, we hybridized many varieties of wheat which are high yield or disease-resistant and selected the F2 population for molecular marker assistant breeding. The results are as follows:1. Henong5290, Zhengzhou5389, and their F3 families were tested for wheat leaf rust resistance with Chinese P. triticina pathotype FHNQ in field. The results showed that the leaf rust resistance in Henong5290 was controlled by one dominant resistance gene, temporarily designated as LrH5.2. BSA and SSR technique were used to test Henong 5290 and their resistant and susceptible bulks of F3 populations for mapping the leaf rust resistance gene. The resistance gene LrH5 was linked to the four known SSR loci(wmc273, wmc557, barc10 and gwm344)on the 7B, and the LrH5 flanked by wmc557 and barc10 with genetic distance 5.2cM and 9.3cM respectively.3. The molecular-assisted selection method was employed to select the 54 F2 generation from crossing between the high-yielding varieties of wheat production and high resistance to leaf rust wheat production which containing resistance genes Lr10, Lr24, Lr34, Lr37 and Lr38. The result of selection is 47 plants contained the aimed resistance genes, that means the the polymeric material can be used to produce the nest generation for the pyramiding. Six of them contained not all the pyramided resistance genes. One plant contained no aimed resistance gene. This result makes the first step for the following breeding process.