The effect of different levels of urea was investigated on the extent of damage of rice
caseworm, Nymphula depunctalis (Gn.). Data were collected on infested hill, tiller,
leaf, number of cases/m2 and position of case in leaf at different ages of the plant viz.
20, 27, 34, 41 and 48 days after transplanting (DAT). Grain yield (t ha-1) was
recorded after harvesting. The infestation of N. depunctalis was significantly different
in all the parameters measured except in the position of case in leaf when different
levels of urea were applied. The highest infestation was observed from the plot
treated with 190 kg urea ha-1 and the minimum from 130 kg. The infestation was
maximum at 27 DAT which declined thereafter. The lowest yield was obtained from
the plot treated with high level of urea. The implication of urea on the level of
infestation of N. depunctalis is discussed.