Integrated management of litchi fruit and shoot borer (Conopomorpha sinensis) using insect growth regulators under subtropics of Bihar

Abstract

A field trial was conducted consecutively for two years at ICAR-National Research Centre on Litchi to develop Insect Growth Regulators based (IGRs) approaches for managing the litchi fruit and shoot borer (Conopomorpha sinensis; Lepidoptera: Gracillariidae) a major pests of litchi causing economical loss. Studies revealed that T4 - novaluron 10 EC 0.015% recorded least infestation (9.62% and 4.70%) during early and mid stage which is closely followed by T2- diflubenzuron 25 WP 0.03% (9.87% and 5.73%). However, at harvest stage, T2 recorded the lowest borer infestation (12.39%) followed by T4 (13.67%) against highest borer infestation (59.35%) in control. Further, highest reduction of borer infestation over control was noticed in T4 (53.25% and 73.56%) followed by T2 (52.04% and 73.99%) during early stage and mid stage, respectively. At harvest stage, most of the treatments showed more than 75% efficacy on reduction in borer infestation over control. The highest reduction in borer infestation was found in T2 (80.65%) followed by T4 (77.50%). The least infested fruit (2.11 kg/tree) and highest healthy fruit (16.38 kg/ tree) was recorded with T2 followed by T1 (14.99 kg/tree), T5 (14.46 kg/tree) and T4 (13.99 kg/tree) against lowest (4.14 kg/tree) in control. Similarly, reduction in fruit infestation over control calculated on weight basis was also highest in T2 (78.77%) followed by T1 (75.79%), T5 (73.85%) and T4 (73.33%).