Influence of climatic factors on populations of the brown plant hopper in Kuttanad, Kerala

Abstract

Studies carried out at the Rice Research Station, Moncompu, Kerala, during 1974-76 showed that in the Kuttanad rice tract, brown plant hopper Nilaparvata /ugens (Stal.) is present in the field throughout the year with a major population peak during January to March for themain crop (winter crop) and a minor peak during August to September for the second crop {autumn crop). Correlation studies revealed that the hopper population was significantly influenced by climatic factors. Rainfall in association with relative humidity and and maximum temperature played a decisive role in regulating the population of the insect.