ヨトウガの相変異 : VIII 発育中に食草の種類を変えられた場合の発育速度と体色に対する密度の働き

概要

論文の詳細を見る
It is well known that the larvae of the cabbage armyworm, Mamestra brassicae take mass-migrations from their original habitat to other food plants when they outbreak. It is the main purpose of this experiment to ascertain whether there are any noticeable characteristics in the adaptability of larvae which were reared under solitary and crowded conditions encountering the food change in their developmental stages. 160 larvae were reared in solitary and 240 larvae in crowd of 10 individuals per vial under the condition controlled temperature at 25℃ and darkness. Young leaves of Chenopodium centrorubrum and Brassica oleracea, natural foods for the larvae, were used for their rearing. For the solitary and crowded larvae eight experimental cultures were prepared. In each culture the larvae were given Chenopodium or Brassica leaves at different larval instar, as shown in Fig. 1. Mortality of the solitary larvae depends almost entirely on the food plant given and the mortality caused by the food changes became higher as they received it in later developmental stages. Mortality of the crowded larvae, however, was not so strongly affected by the food plant in early iarval stages, and almost all of the final instar larvae survived on Chenopodium leaves after they had been reared on Brassica leaves in their preceding instars. Developmental velocity of the solitary larvae are affected by the kind of food plant at any time of their development. On the contrary, the developmental velocity of the crowded larvae was not so strongly affected in youngr stages and also in the final instar, when they were reared on Chenopodium after feeding on Brassica in the preceding instars. In this case it was also a notable result that the larval duration was shorter in the crowded cultures than in the solitary ones. The body colour of the final instar larvae was affected by the larval density and also by the food plant. The tendency of darkening colour in the crowded culture was slightly intensified by changing the food, even if the alternation of food was done just before the final instar.
1963-12-01

ヨトウガの相変異 : VIII 発育中に食草の種類を変えられた場合の発育速度と体色に対する密度の働き

スポンサーリンク

概要

著者

関連論文

スポンサーリンク