Bombyx mori Nucleopolyhedrovirus (BmBPV):Its Impact on Silkworm Rearing and Management Strategies

The mulberry silkworm Bombyx mori (L.) (Lepidoptera: Bombycidae) is infected with a baculovirus, Bombyx mori nucleopolyhedrovirus (BmNPV) that causes grasserie disease in silkworm and major economic losses to the silk industry. In India, >50 % of silk cocoon crop losses are attributed to BmNPV infection. Presently, there are no specific preventive measures for the occurrence and spread of BmNPV infection other than sanitized rearing methods, the only commercial practice today is to discard large stocks of worms in case of infection. Although diagnostic kits for detection of BmNPV have been developed, they are not extensively used on a commercial scale and subsequently, they fail to provide the indispensable and timely advantages desired for early disease intervention. The best emerging technology is the use of antibody–based biosensors and lateral flow assays, which have high specificity, sensitivity and the option of “on– site” pathogen detection. The use of disease resistant silkworm breeds or the utilization of inherent resistance in silkworm would be the most economical and effective way to prevent the occurrence of grasserie disease. Further, there is a great need to comprehensively analyze the host genes response to BmNPV infection and its functional analysis to prevent virus replication and its horizontal transmission.