Effect of Different Host Plants on the Biology of Diamond-Back Moth, Plutella Xylostella Under Laboratory Conditions in Northern Punjab, Pakistan

Plutella xylostella is an oligophagous pest of several host plants belonging to the family Cruciferae (cauliflower, cabbage, canola). This is widely distributed in all those areas where its hosts exist and cause severe crop losses. The current study was conducted to check the effect of host plants such as cabbage, cauliflower and canola on the biology of P. xylostella. The effect on incubation period, growth, development time, fecundity, oviposition, % survival and % egg viability was studied on canola, cabbage and cauliflower. The developmental time from 1st instar to adult emergence was longest (18 days) on canola while shortest on cauliflower (15 days). Fecundity was recorded maximum (259 eggs) on cauliflower and minimum (159 eggs) on canola. Percentage survival of each stage was recorded maximum on cauliflower (84%) followed by cabbage (73%) and canola (69%). A significant difference was observed intheintrinsic rate of increase, rm with host plants. The intrinsic rate of increase(0.290) and finite rate of increase values (1.35) were obtained on cauliflower while 0.283, 1.30 and 0.239, 1.23 on cabbage and canola, respectively. Cauliflower was found to be the most preferable host for P. xylostella due to higher percentage of survival, higher fecundity, higher % egg viability and shorter developmental period. The study provides knowledge about the host plants that prove helpful in enhancing the P. xylostella population.