Midguts of diseased B. mori samples were dissected and genomic DNA was extracted as per standard protocol. The total RNA was isolated using Trizol reagent (Invitrogen) and first strand cDNA synthesized utilizing oligo (dT)18 primers (MWG India Pvt Ltd., Bangalore) and M-MLV Superscript III reverse transcriptase (Invitrogen) (1 μl) as per standard protocol for utilization in the PCRs. Three sets of DNV-2 specific primers viz. DNV-2, VD1 and VD2 as well as one set of NPV specific primers viz. GP41 were designed utilizing the online software program, primer3http://frodo.wi.mit.edu/cgi-bin/primer3/. Two sets of primers were utilized for detection of nsd-2 gene for resistance and susceptibility to DNV-2, respectively (Ito, 2008). B. mori βactin primers were used as internal standard for qPCR studies.