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.
