摘要
通过室内溶液培养试验,研究了硅酸盐对接种稻瘟病菌后水稻的病情指数、植株生物量、过氧化物酶(POD)、多酚氧化酶(PPO)和苯丙氨酸解氨酶(PAL)活性的影响。结果表明:施硅能显著降低水稻稻瘟病的发病率和病情指数,防治效果达60.59%;显著减轻稻瘟病对水稻地上部的危害,干物质量显著高于不施硅处理,但对地下部生长影响不明显;接种后水稻叶片POD活性均升高,在第5 d达到最大值,施硅处理显著低于不施硅处理,与稻瘟病抗性成负相关;水稻叶片PPO活性在接种后第5 d达到峰值,从第4 d开始施硅处理显著高于不施硅处理;接种后水稻叶片的PAL活性快速升高,在第24 h达到最大值,施硅处理显著高于不施硅处理,是其1.44倍。说明硅能提高防御性关键酶的活性,参与水稻本身防卫机制,通过一系列的生理生化作用来增强水稻的抗性。
A series of hydroponics experiments were performed in a controlled rice-Magnaporthe grisea pathosystem to study the effects of silicon （Si） on disease development, plant growth, activities of peroxidase （POD）, polyphenoloxidase （PPO） and phenylalanine ammonia-lyase （PAL）. Silicon （Si） application significantly decreased rice blast incidence and severity index, with control efficiency of 60.59%. Shoot dry weight of rice plants amended with 1.7 mmol/L Si was significantly higher than that of the non-Si-amended plants by 10 d after inoculation with M. grisea. However, No significant difference was observed in root dry weight between the Si＋ （with Si added） and Si- （without Si added） treatments. Application of silicon was beneficial for rice growth and alleviated damage resulting from infection by M. grisea. POD activity increased after inoculation and reached a maximum by 5 d. POD activity in leaves of Si＋ plants was significantly lower than that of Si- plants after inoculation. The result showed that the change
of POD activity was not directly related to rice blast resistance, but might be directly related to damage degree of rice leaves infected by M. grisea. PPO activity in Si＋ and Si- rice plants both slowly increased after inoculation and had a
peak by 5 d. PPO activity in leaves of Si＋ plants was significantly higher than in Si- plants from 4 d and onward. PAL activity in Si＋ and Si- rice plants rapidly increased after inoculation and had a peak by 24 h, thereafter began to decline. However, PAL activity in Si＋ plants was 1.44-fold higher than in Si- plants. It is hypothesized that silicon can mediate activities of key defense enzymes to induce some natural defense responses in rice and play an active and physiological role in enhancing resistance to rice blast.
出处
《植物营养与肥料学报》
CAS
CSCD
北大核心
2009年第5期1023-1028,共6页
Journal of Plant Nutrition and Fertilizers
基金
国家自然科学基金(30671210)资助
关键词
硅
水稻
酶活性
稻瘟病
silicon rice enzyme activity Magnaporthe grisea
