叶面喷施硅和磷对水稻及其抗白背飞虱的影响

【目的】硅可以增强植物的抗病性和对环境胁迫的耐受性，本实验检测了水稻叶面喷施硅和磷后叶片中硅和两种次生物质含量的变化以及喷硅对白背飞虱Sogatella furcifera种群的影响，旨在阐明外源元素施用是否会提高水稻的抗虫性。【方法】采用对分蘖期水稻进行硅肥、磷肥、和两者混合的喷施处理，测定比较了水稻叶片正面和反面硅含量、草酸含量和可溶性糖含量，同时检测了喷施硅肥后水稻叶片硅化细胞数量和取食处理水稻后白背飞虱种群增长的参数。【结果】20和40 mg/L 硅或硅+磷混合施用后，水稻叶片中的硅含量比对照显著增加(P<0.05)。在40 mg/L硅+ 40 mg/L磷喷施处理后，水稻叶片正反面的硅含量分别比对照增加了116%和104.4%。扫描电镜结果显示，处理后的水稻叶片上气孔周围硅化细胞明显增加。此外，硅和磷喷施后3 d和6 d，水稻叶片草酸含量显著增加(P<0.01)。40 mg/L硅处理后的水稻上饲养的白背飞虱产卵量与对照相比明显下降(P<0.05)。【结论】硅+磷喷施处理促进水稻叶片抗虫物质含量增加，硅喷施抑制了白背飞虱的产卵量。

Effects of foliar spraying of silicon and phosphorus on rice (Oryza sativa) plants and their resistance to the white-backed planthopper,Sogatella furcifera (Hemiptera: Delphacidae)

【Aim】 Silica strengthens disease resistance and improves environmental stress tolerance in plants. We examined the changes in the silicon content and some biochemical substances in rice leaves following foliar spraying of silicon and phosphorus, and the effects of spraying silicon on a population of the white-backed planthopper (WBPH), Sogatella furcifera, in order to further understand the enhancement of innate rice resistance to pests by exogenous elements. 【Methods】 After foliar spraying of silicon, phosphorus, and silicon+phosphorus at the tillering stage of rice, the contents of silicon, oxalic acid, and soluble sugar in rice leaves were measured. After foliar spraying of silicon, the silicon cells around the stomata of rice leaf were observed under transmission electron microscopy (TEM), and the population growth parameters of WBPH fed on treated rice were also examined. 【Results】 The silicon content in rice leaves in foliar spray treatment with 20 or 40 mg/L silicon or silicon+phosphorus increased significantly compared to that in the control (P<0.05). The silicon contents on both the upper and lower sides of rice leaves in foliar spray treatment with 40 mg/L silicon+40 mg/L phosphorus increased by 116% and 104.4%, respectively, compared to that in the control (P<0.01). There were more silicon cells around the stomata of treated rice leaves. The oxalic acid content in rice leaves at 3 and 6 d after foliar spray treatment with silicon+phosphorus increased significantly. The soluble sugar content in rice leaves for most silicon+phosphorus combinations increased. The number of eggs laid by per female of S. furcifera fed on rice leaves sprayed with 40 mg/L silicon decreased significantly (P<0.05). 【Conclusion】 The foliar spraying of silicon+phosphorus enhances the innate resistance of rice to pests and induces an increase of resistant substances in rice plants, and decreases the number of eggs laid by the WBPH females.