The Mutagenesis Research On Wheat Near-isogenic Lines TcLr10, TcLr21 And TcLr44

Wheat leaf rust caused by Puccinia triticina is one of the most important diseases affecting the wheat production world-widly. In this research, wheat near-isogenic lines TcLr10 was treated by ⁶⁰Coγ-ray and ethyl methane sulphonate (EMS), wheat near-isogenic lines TcLr21 was complex mutated by ⁶⁰Coγ-rays and sodium azide sis, wheat near-isogenic lines TcLr44 was conducted chemical mutagenesis by ethyl methane sulphonate (EMS) in order to obtain the optimized mutagenesis system and resistance mutations. The results were as follow:1. In this study, the germination rate was determined, and found that the germination rate of mutation TcLr10 was affected by ⁶⁰Coγ-rays and sodium azide. Compared to the chemical doses were significantly different, no distinct differences were found on the germination rate of TcLr21 complex mutagenesis and TcLr44 EMS mutagenesis.2. Complex mutagenesis on near-isogenic lines TcLr21 in wheat by ⁶⁰Coγ-ray and ethyl methane sulfonate was conducted, comparing to the control, the durative time of trefoil stage has distinct differences due to the different dose of physical mutagenesis. However, no significant differences were found in the durative time of trefoil stage of both near-isogenic lines TcLr10 mutated by complex mutagenesis and near-isogenic lines TcLr44 mutated by the ethyl methane sulphonate.3. The contrary tendency was found between the fatality rate and the germination rate in the impact of mortality study of wheat near-isogenic lines TcLr21. after complex mutagenesis. The dose and the concentration of the complex mutagenic contributed the same significant difference. The mortality rate of wheat near-isogenic lines TcLr10 was increased with ⁶⁰Coγradiation dose increasing. And the mortality rates of wheat near-isogenic lines TcLr10 were significant different at 0 Gy and 100 Gy and 150 Gy and 200 Gy.4. The trial focus on wheat resistant changes after mutation was carried out. Three mutants of wheat TcLr10 were obtained after treated by EMS at 0.4% concentration and physical mutation 150Gy. The infection type of leaf rust strain 04-5-90 on TcLr10 was changed from "4" to "2" in the mutant lines. 16 anti-affect mutants were obtained in near-isogenic lines of wheat Mutation TcLr44, and named as follow: Mm4702, Mm4605, Mm4505, Mm4509, Mm4407, Mm4206, Mm3608, Wm4205, Wm4206, Wm4410, Wm4709, Wm3006, Wm3008, Wm3111, Wm4108 and Wm4110. The infection type of leaf rust strain 04-16-1-1 on TcLr44 was from "0" to infection type "3" on Mm4702, Mm4605, Mm4505, Mm4509, Mm4407, Mm4206, Mm3608, Wm4205, Wm4206, Wm4410, Wm4709, Wm3006, Wm3008 and Wm3111, and to infection type "3,4." on Wm4108 and Wm4110. However, only the Mutation II of Wm4205 mutant was harvested of the 16 mutants.The optimized mutagenesis system and the mutants of wheat near-isogenic lines TcLr10 and TcLr44 were obtained which facilitated getting other wheat leaf rust resistance gene mutants in the future. The experiment established the foundation for the functional analysis of wheat leaf rust resistant gene.