THE SESONAL ACTIVITY OF THE MAIN INSECT PARASITOIDS ATTACKING PUPAL STAGE OF THE CABBAGE BUTTERFLY Pieris rapae L. ON DIFFERENT HOST PLANTS.

Abstract

The experiment was carried out at the experimental farm of the Plant Protection Department Sakha Agriculture Research Station, Kafr El-Sheikh, during three successive vegetable growing seasons, 2011/12and 2012/13 on cabbage (Brassica oleracea var. capitata L.), cauliflower (B. oleracea var. botrytis L.), and Canola rape (Brassica napu. oleifera L ). Cabbage plants harboured the highest average percentage of the pupal parasitoids Brachymeria femorata parasitoid during three successive seasons 2011 , 2012 and 2013 represented by 17.5and 18.3% followed by cauliflower plants 13.9 and 14.9 %.While, canola plants recorded the last category and represented by 11.6and 13.9%,respectively .Moreover, there was a highly significant differences between the percentage of B.femorata parasitoids on different cruciferous plants during the two successive seasons .The cabbage plants harboured the highest average percentage of Pteromalus puparum during the three successive seasons 2011/12 and 2012/13 represented by 30.8% and 31.5% followed by cauliflower plants 24.4and 26.6% while, canola plants recorded the last category and represented by 19.6% and 14.7%,respectively .Moreover there were a highly significant differences between the percentage of P. puparum on different cruciferous plants during the two successive seasons. Cabbage plants harboured the highest average percentage of Phryxe vulgaris during three successive seasons 2011/12 and 2012/13 and represented by 8.9% and 8.1% followed by cauliflower plants 5.8and 6.8% while, canola plants recorded the last category and represented by 3.5% and 2.9 % , respectively.Moreover, there were a highly significant differences between the percentage of P. vulgaris on different cruciferous plants during the two successive seasons.