Zhang Guo-Liang, Dai Qi-Gen, Zhang Hong-Cheng
Key Lab for Crop Genetics and Physiology of Jiangsu Province, Yangzhou University, Yangzhou 225009, China.
Zhi Wu Sheng Li Yu Fen Zi Sheng Wu Xue Xue Bao. 2006 Oct;32(5):600-6.
The enhancing resistance and decreasing incidence to sheath blight (Rhizoctonia solani) by silicon were studied from cytological and physiological aspects by using rice plants solution-cultured with silicon supplementation or with silicon-deficiency. By an environmental scanning electron coupled with X-ray microanalysis, as well as gravimetric 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 always higher than that in Si(-) rice plants, SOD activity 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 harmony of 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 index with relative control effect of 1/4 compared to the Si(-) rice plants (Table 2).
通过使用添加硅或缺乏硅的溶液培养水稻植株，从细胞学和生理学方面研究了硅对水稻纹枯病（立枯丝核菌）抗性增强和发病率降低的影响。通过环境扫描电子显微镜结合X射线微分析以及重量法测定，施硅水稻叶片的硅质细胞数量和硅含量远高于缺硅水稻叶片（图1、2；表1）。接种立枯丝核菌后，施硅水稻植株的丙二醛（MDA）含量几乎始终高于缺硅水稻植株，施硅水稻植株的超氧化物歧化酶（SOD）活性始终高于缺硅水稻植株，施硅水稻植株的SOD活性在第4天达到最低，而过氧化物酶（POD）活性达到最高，但缺硅水稻植株的POD活性较低。这些结果表明硅可以增强SOD和POD的协调性。硅对过氧化氢酶（CAT）和苯丙氨酸解氨酶（PAL）活性没有影响，但会削弱多酚氧化酶（PPO）活性（图3）。接种立枯丝核菌后，施硅水稻植株的病情指数显著低于缺硅水稻植株，相对防效为缺硅水稻植株的1/4（表2）。
