摘要
通过盆栽试验研究增强UV-B辐射和稻瘟病菌(Magnaporthe grisea)联合作用对水稻(Oryza sativa L.)幼苗生长和病害的影响。试验采用4个UV-B辐射强度(0、2.5kJ·m-2、5.0kJ·m-2和7.5kJ·m-2)和两个稻瘟病菌生理小种(Y98-16T和Y99-63C)对2个水稻品种(黄壳糯和合系41)进行处理,以及4个UV-B辐射强度对2个稻瘟病菌生理小种处理。测定水稻的株高、生物量和病情指数,以及稻瘟病菌菌落生长速率的变化。结果表明:(1)增强UV-B辐射7d再接种稻瘟病菌处理与只接种稻瘟病菌处理相比,导致2个水稻品种病情指数显著降低,最大降幅为2.5kJ·m-2-Y98-16T处理后的合系41,达83.5%,病害明显减轻。这可能是UV-B辐射诱导水稻形态结构和生理生化发生一定的变化,抵御病害的能力加强。(2)先接种稻瘟病菌Y98-16T再进行不同的UV-B辐射与只接种稻瘟病菌的处理相比,黄壳糯和合系41的病情指数均显著升高,最大增幅为Y98-16T-7.5kJ·m-2处理后的合系41,达53.7%,病害加剧,且利用UV-B直接辐射稻瘟病菌Y98-16T,其生长速率总体上呈显著增加。(3)接种稻瘟病菌Y99-63C后进行不同的UV-B辐射与只接种稻瘟病的处理相比,2个水稻品种的病情指数均没有显著变化,总体上,UV-B辐射对稻瘟病菌Y99-63C的生长速率没有影响。
Effects of UV-B radiation and Magnaporthe grisea on growth and blast of two rice （Oryza sativa L.） cultivars were stud- ied by pot experiments. Two rice cultivars （Huangkenuo and Hexi-41） were treated by four enhanced UV-B radiation levels （0, 2.5, 5.0 and 7.5 kJ-m-2） and two blast isolates （Y98-16T and Y99-63C）, whilst two blast isolates （Y98-16T and Y99-63C） were radiated by four enhanced UV-B radiation levels （0, 2.5, 5.0 and 7.5 kJ·m2）. Changes of plant height, biomass and disease index office, and growth rates of Magnaporthe grisea were determined. Experimental results were gotten. Comparing with inoculated two blast iso- lates, enhanced UV-B radiation 7 days and then inoculated two blast isolates could decrease disease index of two rice cultivars. Hexi-41 showed the largest decrease in disease index by 83.5% with the treatment of 2.5 kJ.m2-Y98-16T. Blast disease in Hexi-41 was reduced. UV-B radiation might change morphology and physiology of rice, increase the capacity of rice for resisting blast. Comparing with inoculatedY98-16T, inoculated Y98-16T and then enhanced UV-B radiation increased disease index of two cultivars. The largest increase in disease index was 53.7% in Hexi-41 with the treatment of Y98-16T-7.5 kJ.m-2. Blast disease in Hexi-41 was exacerbated. In general, UV-B radiation increased the growth rates of Y98-16T directly. Comparing with inoculated Y99-63C, inocu- lated Y99-63C and then enhanced UV-B radiation, disease index of two rice cultivars was not changed. UV-B radiation had no effect on the growth rates of Y99-63C.
出处
《生态环境学报》
CSCD
北大核心
2009年第3期1026-1030,共5页
Ecology and Environmental Sciences
基金
国家博士点基金项目(20060676002)
