ABUNDANCE, LEAF FEEDING AND CONTROL OF EPILACHNA BEETLE IN BRINJAL AT PSTU CAMPUS

ABSTRACT: The production of the brinjal is hampered due to severe infestation by epilachna beetle. The experiment was conducted to investigate the abundance of epilachna beetle on brinjal at Patuakhali Science and Technology University (PSTU) campus during January to May 2022 and to determine the effectiveness of different insecticides on mortality and leaf consumption. Three treatments viz., T1 = Caught 10 EC @ 1 mlL-1 of water, T2 = Bioclean (D-Limonin 5% M L) @ 1 mlL-1 of water, T3 = Fyfanon 57 EC @ 1 mlL-1 of water and an untreated control. Results revealed that the highest number of grub (31.5) and adult (2.06) per plant was recorded in May while the lowest in January. The highest leaf area (35%) consumed by the grub was observed at 72 hours after release (HAR) followed by 48 HAR (28%) but the lowest (23%) in 24 HAR. Similar trend was also observed in leaf area consumed by adult beetle at 72, 48 and 24 HAR. The mortality of grub and adults were recorded 100% from the leaf treated by T1 (Caught 10 EC @ 1 ml L-1 of water), T2 (Bioclean (D-Limonin 5% M L) @ 1 mlL-1 of water) and T3 (Fyfanon 57 EC @ 1 mlL-1 of water) while no mortality was observed in the untreated control. No leaf consumption by epilachna beetle was observed after 24 hours of release when treated by T1 (Caught 10 EC @ 1 mlL-1 of water), T2 (Bioclean (D-Limonin 5% M L) @ 1 mlL-1 of water) and T3 (Fyfanon 57 EC @ 1 mlL-1 of water) while 24% and 17% leaf consumption by grub and adult, respectively in the untreated control. Though all these treatments were effective for controlling epilachna beetle but Bioclean could be the best option for ecofriendly management. 

Keywords: Epilachna beetle, Incidence, leaf consumption, insecticidal efficacy.