Seasonal incidence of tobacco leaf eating caterpillar, Spodoptera litura (FAB.) infesting groundnut (Arachis hypogaea L.)

Abstract

The present study entitled, “Seasonal incidence of tobacco leaf eating caterpillar, Spodoptera litura (Fab.) infesting groundnut (Arachis hypogaea L.)” was carried out at the Experimental field of AICRP on groundnut, Cotton Improvement Project, MPKV, Rahuri, during kharif 2023-24. The study revealed that, S. litura larval population ranged from 0.23-5.23 larvae/mrl (metre row length) during the crop growth period. S. litura larval incidence was noticed in 31st Standard Meteorological Week (SMW) (0.23 larvae/mrl) and lasted upto 43rd SMW (0.31 larvae/mrl). Minimum population of S. litura was noticed in 31st SMW i.e. 1st week of August. Afterwards, population of S. litura gradually increased upto 34th SMW i.e. 4th week of August (4.34 larvae/mrl) and reached to its peak of 5.23 larvae/mrl during 36th SMW i.e. 1st week of September. Highly significant positive correlation was noticed between incidence of S. litura and evening relative humidity (r = 0.541). However, highly significant negative correlation was noticed between S. litura incidence and rainfall (r = - 0.592). The correlation coefficient showed nonsignificant positive correlation between population of S. litura and minimum temperature (r = 0.481) whereas, nonsignificant negative correlation was noticed between S. litura larval population and maximum temperature (r = - 0.191) and morning relative humidity (r = - 0.538).