冈优725对四个稻瘟病菌生理小种毒素的响应

Response of Gangyou725 to the toxin of four rice blast fungus Magnaporthe oryzae physiological races

为了明确稻瘟病菌对杂交水稻的毒害机制,采用稻瘟病菌粗毒素浇灌水稻植株,探讨4个稻瘟病菌生理小种的粗毒素对冈优725各器官物质积累、转运及产量的影响规律。结果显示:4个稻瘟病菌生理小种毒素均不同程度地抑制了冈优725干物质积累并引起大幅减产,根部干物质积累量、地上部干物质积累量、有效输出率、有效转化率平均下降34.57%、21.48%、31.34%、40.90%;穗粒数、结实率、千粒重和产量平均降低17.24%、12.84%、5.65%和10.83%;生理小种间毒力差异显著,其中ZA10毒素的毒性最强;孕穗期是冈优725对稻瘟病菌毒素最敏感的时期。

To understand the toxic mechanism of Magnaporthe oryzae on rice, the effects of four physio- logical races of M. oryzae were conducted on the matter accumulation, translocation, and yield properties relating to hybrid rice. The results showed that the toxin of four physiological races of M. oryzae reduced dry matter accumulation and yield significantly. Dry matter accumulation of roots and aerial parts de- creased by 34.57% and 21.48%, respectively. So did the effective output by 31.34%, the effective conversion by 40.90%, grains per spike by 17.24%, seed setting rates by 12.84%, 1000-grain weight and yield by 5.65% and 10.83%, respectively. There were significant differences among four physiolog- ical races, of which the toxin ZA10 possessed higher toxic effect than the rest three ones. The booting stage was the more sensitive period to toxins for Gangyou725 than the other stages.