Effect of silica amendment on brown planthopper infestation in susceptible and resistant rice varieties

Abstract

The brown planthopper (BPH, Nilaparvata lugens) remains a major constraint in rice production across Asia, causing yield losses of up to 60–100% under severe infestation. Excessive reliance on chemical insecticides has proven unsustainable, leading to resistance, resurgence, and ecological risks. This study evaluated the effectiveness of liquid silica as an eco-friendly alternative to suppress BPH populations across different rice varieties. A factorial randomized complete design was employed, involving four silica concentrations (0, 0.30, 0.62, and 0.94 g/L) and three varieties (Ciherang, IR64, MR337), with three replications. Results indicated that silica application significantly affected both mortality and natality of BPH. The highest mortality was observed at 0.94 g/L, particularly on MR337, while natality was drastically reduced to zero in most treatments. Ciherang under control conditions recorded the highest natality, whereas IR64 exhibited relatively better natural resistance. These findings highlight that silica not only enhances rice resistance but also serves as a potential biological control agent. Therefore, liquid silica fertilizer offers strong potential as an integral component of sustainable integrated pest management strategies, contributing to improved rice productivity and food security.