Diseases and Pests of Silkworm

The profitable silk industry faces constant pressure from disease and predation, threatened not just by viral, fungal, bacterial and protozoan infections but also by insect predators, birds and larger animals — ants, crows, kites and rats all feed on silkworms and cause real losses. The most dangerous silkworm disease is Pebrine, caused by the protozoan Nosema bombycis, which spreads both through the mother silkworm's eggs and by ingestion of contaminated food. Flacherie mainly affects mature larvae and is caused chiefly by bacteria such as Streptococcus and Staphylococcus. Grasserie, the most dominant and serious viral disease, is caused by Bombyx mori nuclear polyhedrosis virus (BmNPV), a Baculovirus belonging to sub-group …