The Complete Guide to Silkworm Breeds: Get to Know Common Silkworm Varieties

Silkworm breeds are broadly divided into three categories:

1. Univoltine silkworm breeds

Depending on the breed, the silkworm (Bombyx mori) produces only one generation within a year and then lays diapause eggs; these are called univoltine silkworm breeds. Such breeds develop slowly, take many days to complete their life cycle, consume a large amount of mulberry leaves during the larval stage, and have larger bodies and cocoons with the highest silk yield, but they are physically weak and not suited to hot, humid climatic conditions, making them suitable for rearing in temperate regions.

2. Bivoltine silkworm breeds

Those that produce two generations within a year, that is, the first generation lays non-diapause eggs and the second generation lays diapause eggs, are called bivoltine silkworm breeds. The larval stage of such breeds is shorter than that of univoltine breeds, and they are robust and develop uniformly, with only a slightly lower cocoon shell weight than univoltine breeds. Most current varieties are bivoltine breeds that have been improved by introducing the excellent cocoon and silk quality traits of univoltine breeds, and they are suitable for rearing in warm zones and during the summer-autumn silkworm rearing season.

3. Multivoltine silkworm breeds

Those that produce three or more generations within a year are generally called multivoltine silkworm breeds, and the last generation may lay either diapause eggs or non-diapause eggs; the former are called multivoltine silkworm breeds with a diapause stage, and the latter are called multivoltine silkworm breeds without a diapause stage. Such breeds develop quickly, with an extremely short larval stage. They are extremely robust, with small cocoons and a low silk yield; the silk filaments are fine in size, with few separated fine fibers, and the silk quality is slightly inferior.