施硅增强水稻对纹枯病的抗性

采用水培的方法，从细胞学和生理生化方面研究了硅增强水稻对纹枯病的抗性作用。结果表明：加硅处理的水稻叶片硅化细胞和叶片表面的硅元素含量均显著高于缺硅处理（对照）：接种纹枯病菌后，加硅处理的MDA含量总体上低于缺硅处理，峰值尤为显著；加硅处理的SOD活性始终高于缺硅处理，接种后第4天加硅处理SOD活性较低时，其POD活性较高，而缺硅处理的POD活性较低，表明硅增强了SOD和POD之间的协调性；接种后硅对CAT和PAL活性没有产生明显影响，但降低了PP0活性；加硅能显著降低水稻植株的纹枯病病情指数。

Silicon Application Enhances Resistance to Sheath Blight (Rhizoctonia solani) in Rice

The enhancing resistance and decreas-ing incidence to sheath blight(Rhizoctonia solani)by silicon were studied from cytological and physi-ological aspects by using rice plants solution-cul-tured with si1icon supplementation or with si1icon-deficience.By an environmental scanning electron coupled with X-ray microanalysis,as well as gravi-metric quantification,the number of siliceous cell and Si content of the Si+ rice leaf were much more than those of Si-rice leaf(Figs.1,2;Table 1).After being inoculated with R.solani MDA content in Si+ rice plants was almost higher than that in Si-rice plants,SOD activity in Si+ rice plants was al-ways higher than that in Si-rice plants,SOD activ-ity in Si+ rice plants reached a minimum on 4 d,and POD activity was at the maximum,but POD activity in Si-rice plants was lower.These results suggested that silicon could enhance the harmonyof SOD and POD.And silicon had no effect on CAT and PAL activity,but weaken PPO activity(Fig.3).After being inoculated with R.solani,the Si+ rice plants had significantly lower disease in-dex with relative control effect of 1/4 compared to the Si-rice plants(Table 2).