关键词: 甜瓜, 白粉病, 硅化物, 硅分布, 过氧化物酶

Abstract: The seedlings of Melon Yujinxiang were used to study the effect and inhibitory mechanism of silicon compounds on mildew powder. The results showed that the severity of mildew powder of melon seedling decreased significantly by treatments with two silicon compounds. Sodium silicate was more effect on mildew powder than nanosized silicon. Sodium silicate increased. the activity of resistant-enzyme. Peroxidase (POD) activity was increased significantly by sodium silicate treatment after silicon treated and pathogen-inoculation. -1,3-glocosidase (GLU) activity increased significantly after 120 h of treatment by sodium silicate and 120 h after pathogen-inoculation. Silicon of sodium silicate treatment deposited obviously at stomata and epidermis. Nanosized silicon did not induce POD activity. And silicon deposition of nanosized silicon treatment was as the same as sodium silicate treatment.

Key words: Cucumis melon L., Sphaerotheca cucurbitae, Silicon compounds, Silicon distribution, POD, GLU