Population dynamics of diamond back moth (Plutella xylostella Linn.) on winter cabbage

First incidence of Diamond back Moth was started in second week of February. Infestation of the pest increased gradually and reached peak in first week of March and thereafter declined subsequently in coming Meteorological weeks. Minimum temperature , Morning relative humidity and Rainfall showed significantly positive correlation where as Maximum temperature and Bright Sunshine hours showed non significantly negative correlation with the population of Diamond back Moth.