Effect of age of cauliflower plant on oviposition preference of Spodoptera litura

Study was conducted to determine the most preferred age of the cauliflower plant for oviposition by Spodoptera litura and their relationship. Choice test under net house condition and no-choice test under screen cage were conducted to find out the oviposition preference. Four different dates of sowing were undertaken to obtain differently aged plants to conduct the oviposition test. Age of the plants was categorised based on leaf-age and total life span of cauliflower based on rainy season crop. All the ages of cauliflower plants subjected to oviposition test were acceptable to S. litura female. S. litura mostly preferred to lay more number of eggs on maturing plants particularly 60-80 DAS. In choice test, number of egg masses varied from 0.25 to 4.75 with highest number of egg masses being recorded on 65 DAS plants. S. litura female laid significantly more number of egg masses on 65 DAS (8.46) plants and less number of egg masses on 110 DAS (4.60) plants under screen cage. S. litura gave less preference to young (< 60 DAS) and aged plants (>90 DAS) for oviposition in both choice and no-choice tests. There was no significant correlation observed between age of the plants and number of egg masses. Quadratic nonlinear relationship existed between age of the plants and oviposition preference.