Abstract:    【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.  

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