Population Dynamics of Aphid and Pod Borer on Lentil and their Natural Enemies during rabi Season 2017 at Pusa, Samastipur

Abstract

In order to determine the seasonal incidence and to explore the possibilities of management of aphid and pod borer on lentil through various tactics, a series of field experiments were conducted at Research Farm of Tirhut College of Agriculture, Dholi, Muzaffarpur, The incidence of aphid (Aphis craccivora),  started from 4th meteorological standard week (MSW) (23.80 aphid/10 cm apical twigs). The aphid population gradually increased and reached to its peak (35.4 aphid/10cm apical twigs) on 7th MSW (22nd February) and thereafter its population gradually decreased from 8th MSW 4th  week of February (31.30 aphid/10 cm apical twigs) to 12th MSW(4th  week of March) (9.0 aphid/10cm apical twigs). The incidence of pod borer (Etiella zinckenella)  was observed from 7th MSW(3rd week of February) (4.00%) and the per cent pod damage gradually increased and reached to its peak (14.30 %) on 9th MSW (1st week of march). Its infestation gradually decrease 10th MSW (12.10 %) onwards. Initially Coccinella. septempunctata   population was very low in 4th MSW of January, 2018 (0.90/plant) and after that the population gradually increased. The maximum population of C. septempunctata (4.50/plant) was recorded in 8th MSW of February, 2018. Spider population was very low (1.10 spider/plant) in 4th MSW of January, 2018 and the maximum population (2.00 spider/plant)of spider was recorded in 6th SMW of February.