Seasonal incidence of rice swarming caterpillar, Spodoptera mauritia boisd. Infesting paddy (Oryza sativa L.) Nursery

Abstract

Seasonal incidence of Rice swarming caterpillar, Spodoptera mauritia Boisd. Infesting paddy was recorded during June to August 2017, at Regional Agricultural Research Station, Warangal, and Telangana, India. Study revealed that the no incidence of Rice swarming caterpillar, (0.00 caterpillar/tray) was observed during 1st week of August (31st Standard Meteorological Week). The population of Rice swarming caterpillar suddenly increased and reached to its peak in the 3rd week of August (33rd SMW) with a mean of 150.5 caterpillar/tray in nursery, when the mean atmosphere temperature and relative humidity were 26.99 0C and 80.23 per cent, respectively. Thereafter, the population declined gradually and reached to a minimum level of 10.00/tray during 4th week of August (34th SMW). This result revealed that prolonged dry condition followed by heavy rainfall favoured the outbreak of S. mauritia and exhibited a significant positive correlation with relative humidity and total rainfall, however negatively non-significant with temperature.