3个空间诱变水稻品系的稻瘟病抗性评价及抗性遗传分析

摘要

The rice blast resistance (R) could be evaluated entirely by investigating the resistance spectrum at seedling stage and neck blast resistance at adult stage. In this study, three space-induced rice mutant lines, which had been screened primarily, were performed with resistance spectra with 36 blast i-solates from Guangdong Province and neck blast resistance in a natural blast nursery, Lutian, Conghua. The results indicated that the mutant lines conferred broad resistance spectra and high level of resistance to neck blast, while the on-ground control was highly susceptible. Genetic analysis showed that a single major dominant R gene conditioned H4's and Hll's resistance to isolates GD0193 and GD866, and there were two independent dominant R genes in H4 and Hll corresponding to isoaltes GD08T4 and GD08T13, respectively. The inherited pattern of resistance in D69 to isolates GD0193 was complicated, while a single dominant major R gene controlled its resistance to isolate GD08T4 and GD866.%综合考察水稻苗期叶瘟抗谱和成株期穗颈瘟抗性可以全面地评价水稻种质的稻瘟病抗性.本研究采用来自广东不同稻作区的36个稻瘟病菌株,对经过抗性初筛的3个空间诱变水稻品系进行苗期叶瘟抗谱测定;同时种植于代表性自然诱发病圃——广东省从化市吕田镇,考察其穗颈瘟抗性.结果显示,入选的3个诱变品系具有广谱的苗期叶瘟抗谱、且高抗穗颈瘟,抗性明显优于非诱变原种.遗传分析结果表明,H4和H11对菌株GD0193和GD866的抗性均由主效单基因控制,H4对菌株GD08T4、H11对菌株GD08T13的抗性均由2个独立遗传的显性基因控制,D69对菌株GD0193的抗性遗传模式复杂,D69对菌株GD08T4和GD866的抗性为主效单基因模式.