Evaluation of biopesticides against rice black bug

Abstract

Rice black bug is the major pest of rice in Thiruvallur and Kancheepuram districts. Yield loss at 10 bugs per hill in susceptible cultivars was estimated as 23%. In this context, biopesticide like neem oil (3%), Metarhizium anisopliae (1 × 108 spores) and new molecules profenophos (1000 ml/ha.) were tested against black bug. The results revealed that black bug population was found to be significantly low in profenophos (1000 ml/ha.) sprayed plots 2.0 no./hill. Population reduction was 60.8% followed by Metarhizium anisopliae (1 × 108 spores) applied plots. In neem oil applied plots black bug population ranged from 3.0 no/hill to 3.3 no. /hill whereas control plot recorded the maximum population of 5.1 bugs / hill. © 376.