Abstract
The present paper deals with the effects of temperature of incubation stage and light conditions throughout the larval stages on the voltinism of the silkworms (of six races) reared on artificial diet and mulberry leaves, respectively. The results obtained were as follows; (1) The voltinism of silkworms reared on artificial diet was more sensitive to environmental conditions than that of silkworms reared on mulberry leaves. (2) The voltinism of silkworm on artificial diet was strongly affected by the temperature of incubation stage and the light conditions of larval stages. On the other hand, the voltinism of silkworm reared on mulberry leaves was mainly affected by the temperature of incubation stage, but the effect of the light conditions of larval stages seemed little, if any. (3) The effects of food, temperature of incubation stage and light conditions of larval stages on the voltinism of silkworms varied among the silkworm races. In the six races employed, the voltinism of two Chinese races (C. 140 and BC 9) was strongly affected by the food and environmental conditions.
