Persistence of phorate in different soil types and effect on brown plant hopper, Nilaparvata lugens (Stal)

Greenhouse studies were undertaken to evaluate the persistence of phorate 10 G in different types of soil viz., red sandy loam, black sandy loam, clay and alkaline sandy clay loam in relation to control of brown plant hopper (BPH). Mortality of Nilaparvata lugens was moderate to low in red sandy loam and clay soils with no perceptible mortality in black sandy loam and alkaline soils. Residues were maximum at 10 days after treatments (DT) & thereafter declined. Maximum persistence was observed in plants grown in, alkaline soil while persistence was maximum in water from black sandy loam. In soils, phorate sulfone was higher than phorate from 1 DT in red sandy loam and 10 DT in other three soil types.