Field Evaluation of Newer Insecticides against Spotted Pod Borer [Maruca vitrata (Geyer)], on Blackgram (Vigna mungo L.) in North Coastal Andhra Pradesh

Abstract

Aims: To evaluate the efficacy of novel insecticides against the spotted pod borer on rice fallow blackgram. Study Design: Randomised Block Design (RBD) was used in this study. Place and Duration of Work: The present study was carried out at College farm Agricultural College, Naira during Rabi 2017-2018 season. Methodology: The spotted pod borer, Maruca vitrata (Geyer) is a serious pest of blackgram through out the growth period especially in flowering and pod development stages in North Coastal Andhra Pradesh. Management of this pest becomes difficult due to its concealed nature of feeding inside flowers and pods. Different newer insecticides were evaluated for the management of M. vitrata on blackgram cultivar LBG-752 under rice fallow situations with ten treatments replicated thrice. Results: The current study indicated that among all the insecticidal treatments chlorantraniliprole 9.3% + λ cyhalothrin 4.6% @ 0.5 ml l-1 was found to be very effective by recording 75.91 per cent overall mean reduction in M. vitrata larval population with lowest pod damage (7.04%) over control (60.58%) and also recorded highest grain yield (8.31 q ha-1) followed by chlorantraniliprole 18.5 SC @ 0.0037% and flubendiamide @ 39.35 SC 0.00787% with 72.04 and 67.30 per cent overall reduction in mean larval population of M. vitrata over untreated control. The cost - benefit (C:B) ratio for all the treatments revealed that chlorantraniliprole 18.5 SC @ 0.0037% was highly economical with a C : B of 1: 17.14 followed by spinosad 45 SC with cost - benefit (C:B) ratio 1: 15.28. Conclusion: Usage of newer insecticides with novel modes of action are highly effective against spotted pod borer with an additional increase in yield of blackgram.