Abstract
In Gunma Prefecture after World War II, the revival of the silk industry progressed smoothly, but the revival of the sericulture industry, which produces the cocoons used as raw materials, was delayed. This is because farmers prioritized field farming over sericulture in the context of food shortages immediately after the end of the war. It was after 1949 that the production of cocoons began to increase. However, the growth rate of production after reconstruction was slower in sericulture than in the silk industry. The slow recovery of sericulture, which is agriculture, and the gap in productivity with the silk industry, which is industry, have resulted in a chronic shortage of cocoons. In addition, one of the important factors that promoted the revival of the silkworm industry in Gunma Prefecture after the war was the popularization of communal rearing of juvenile silkworms. Since sericulture is greatly influenced by rearing of young silkworms, various rearing methods have been devised. In the 1950s, the Gunma Sericulture Experiment Station developed the "Gunma-style simple co-raising method for juvenile silkworms," which rapidly spread within the prefecture. It contributed greatly to the reduction of various expenses such as utility bills.
https://ror.org/04kp2z675 
