BADAL BHATTACHARYA, UTPAL BHUYAN, P. BORAH AND DWIBAN PUJARI

The seasonal incidence of cutworm, Agrotis ispilon (Hfn) in potato crop raised from TPS was investigated at Assam Agricultural University (A.A.U.), Jorhat during 2005-06 and 2006-07. The study revealed that the TPS nursery beds were completely free from cutworm infestation during the period of experimentation. Incidence of larvae of cutworm initiated from last week of November to 2nd week of December and reached its peak (2.2 and 2.6 larvae per/pit during 2005-06 and 2006-07, respectively) in between 2nd week of December to 2nd week of January. The larval activity continued for more than seventy-five days. The pupal stages were recorded from mid January till the second week of March with a peak population (1.2 pupae per pit) in the second week of February. The first appearance of moths was observed in November and the activity of the moths continued up to December reaching its peak population (11 and 13 nos. of moths/ catches during 2005-06 and 2006-07 respectively) in the last week of November. The reemergence of the moths was observed from the 2nd week 2005 and 3rd week of February 2006 and continued their activity till the end of 2nd week of March.