龟纹瓢虫选择取食行为的研究

通过室内实验初次研究了龟纹瓢虫取食5种蚜虫行为及其食蚜量;比较了取食5种蚜虫对幼虫生长发育及成虫生殖产卵的影响。结果表明:龟纹瓢虫成虫和幼虫对同种蚜虫的嗜食程度基本相同。初龄幼虫无选择适宜猎物蚜虫的能力。幼虫随龄期的增大,选择能力渐趋明显,以成虫和大龄幼虫选择力更强。该种瓢虫明显选择取食棉蚜、桃蚜和白杨毛蚜,洋槐蚜为不甚适宜的猎物,而甘蓝蚜最不适宜。因此认为,龟纹瓢虫具有一定程度的食物专化性,可作为棉蚜和桃蚜的有效天敌,应充分加以保护与利用。

STUDIES ON THE SELECTIVE FEEDING BEHAVIOUR OF THE LADYBEETLE, PROPYLEA JAPONICA ( THUNBERG)

The feeding behaviour and voracity of the larva and adult of Propylea japonica (Thunberg) for five aphid species were studied and comparisions Were made on the effects of these foods on larval development and adult fecundity of the ladybeetle in laboratory. The results showed that preference of the adult was similar to that of the larva for the same species of aphids. The first instar larva showed no selection for suitable aphids, but the preference was more apparent with the increase of instars and it became stronger in the later instars and the adult. Of the five species of aphids Aphis gossypii Glover, Myzus persicae (Sulzcr) and Chaitophorus populcii Panzer were their most favored foods. Aphis robinae Macchiati was less preferred, while Brevicorync brassicae (L.) was the least preferred. The conclusion can be, therefore, drawn that the lady-beetle, Propylea japonica, has a certain degree of specificity for prey, and can be used as an effective predator for Aphis gossypii and M yzus persicae, So it should be protected and utilized as much as possible.