Habitat manipulation for managing insect pests of Brinjal

Abstract

Field experiments were conducted at Allengmora, Jorhat during 2017–18 and 2018–19 to study the impact of habitat manipulation on the incidence of major pests of brinjal and their natural enemies. There were four treatments comprised of brinjal intercropped with coriander and carrot as border crop (T1); brinjal intercropped with carrot and cowpea as border crop (T2); brinjal intercropped with cowpea and coriander as border crop (T3) and brinjal as sole crop (T4). The results revealed that brinjal intercropped with carrot and cowpea as border crop (T2) was found to be the best in reducing the incidence of shoot (10.53%) and fruit (11.59%) damage. This treatment also reduced the population of Amrasca biguttula biguttula, Henosepilachna vigintioctopunctata and Aphis gossypii to 1.28, 1.73 and 1.89/leaf, respectively. Moreover, maximum numbers of coccinellid predators (2.41/leaves) with maximum yield of 19742 kg/ha and maximum cost benefit ratio (1: 4.25) was obtained with the same module. Thus, brinjal intercropped with carrot and cowpea as border crop could be adopted for effective management of key pests of brinjal.