HOST PLANT PREFERENCE OF THE CABBAGE BUTTERFLY Pieris rapae L ON DIFFERENT CRUCIFEROUS VEGETABLES , IN KAFR EL-SHEIKH REGION.

Abstract

The experiment was carried out at the experimental farm of the Plant Protection Dep. Sakha Agric. Res. Station, Kafr El-Sheikh, during two successive vegetable growing seasons, 2011/ 12 on Cabbage , Cauliflower and Canola plants. Cabbage plants harboured the highest average number of eggs during the two successive seasons 2011/12 and represented by59.2±3.8 and 56.6±3.5eggs/50 plants followed by cauliflower plants 56.9±4.6 and 43.8±2.0 eggs /50 plants while, canola plants recorded the last category and represented by 24.5±2.8 and 35.8±3.1 eggs /50 plants , respectively .Moreover , there was a highly significant difference between the number of egg-laying on different cruciferous plants during the two successive seasons.Cabbage plants recorded the highest average number of larvae during the two successive seasons 2011 /12 and represented by 46.8±5.7 and 45.9±5.3larvae/50 plants followed by cauliflower plants 39.9±5.4 and 36.9±2.9 larvae/50 plants while, canola plants recorded the last category and represented by 17.9±2.5 and 20±2.9 larvae/50 plants ,respectively .Moreover, there were a highly significant differences between the number of larvae on different cruciferous plants during the two successive seasons. Cabbage plants recorded the highest average number of pupa during the two successive seasons 2011/12 and represented by 36.3±6.2 and 37.2±4.5 pupa/50 plants followed by cauliflower plants 32.9±5 and 31.2±4.8 pupa/50 plants while, canola plants recorded the last category and represented by 17.3±2.6and16.3±2.5pupa/50 plants respectively. Moreover, there was a highly significant difference between the number of pupa on different cruciferous plants during the two successive seasons..