Silicon Plays an Effective Role in Integrated Pest Management against Rice Leaffolder Cnaphalocrocis medinalis Guenée (Lepidoptera: Pyralidae)

Abstract

Rice leaffolder, Cnaphalocrocis medinalis (Guenée), is one of the most destructive and key pests of rice in Asian countries. Effective insecticides are available to cope with this pest, but this solution is not a long-term strategy because of apprehensions about health and environmental hazards, exposure risks, residual perseverance and development of resistance. So there is a need to find out an alternate practice for the management of this pest. Pest damage may be reduced through the proper management of nutrients requirements and modifications with mineral nutrients such as Silicon (Si). In this experiment, Si amendments, at the rate of 1.25 and 2.50 g Sikg-1 soil were applied under controlled conditions to investigate the resistance impact on developmental stages and food consumption rate of C. medinalis. Results indicated that Si addition at both low and high levels to rice plant significantly extended the larval development and reduced survival rate of both larvae and pupae. Si amendments reduced larval and pupae weight as compared to control treatment. However, the consumption of green matter increased in Si treated plants by 3rd instar larvae of C. medinalis. Results also showed that enhanced Si level in rice plants reduces food quality and increases plant resistance to the C. medinalis in rice variety. This study concluded that Si fertilizers may play an effective role in C. medinalis management for rice crop protection.