幼虫の年令分布が個体群の増殖におよぼす影響 : コナマダラメイガの増殖能力におよぼす棲息密度の影響(V)

抄録

Using the almond moth, Ephestia cautella W., it was examined under the experimentally controlled condition of temperature (30℃) and relative humidity (70 per cent), how the initial egg density influences the number of moths emerged and the average head width of them when the number of eggs and the times of their introduction to the rice bran are changed. The mountain shaped relation between the egg density and the number of moths emerged was seen in the case of simultaneous introduction of eggs. But, when the eggs were put into the food in two or three times half by half or t third by a third respectively at given intervals, the relation was changed in its shape to the saturation type in consequence of the increase of number of moths in the higher densities and their decrease in the intermediate densities. In these latter cases the average head width of moths increased in the higher egg densities. The curvilinear relation between the initial egg density and the total number of eggs deposited in the next generation, which are expected to be deposited by the female moths emerged was obtained as shown in Fig. 5. This relation changes from a mountain shape to the saturation type by these experimental procedures in both cases of the representation (the reproduction curve) when the relation is calculated by their number and their average head width.