Horseradish peroxidase-labelled probes and enhanced chemiluminescence to detect baculoviruses in gypsy moth and eastern spruce budworm larvae

Horseradish peroxidase-labelled whole genomic DNA probes and enhanced chemiluminescence procedures were utilized to detect baculovirus in insect macerates blotted on nylon membranes. Detection levels were similar to those found using 32P-labelled probes; 5·10 3 occlusion bodies (OBs), 2·10 3 OBs and 4·10 4 OBs of Lymantria dispar (L.) nuclear polyhedrosis virus (LdNPV), Choristoneura fumiferana (Clem.) NPV (CfNPV) and C. fumiferana granulosis virus (CfGV) respectively using 10 ng/ml LdNPV DNA probe and 20 ng/ml CfNPV and CfGV probe concentrations. Quantities of purified viral DNA detected were 0.56 ng LdNPV, 0.20 ng CfNPV and 0.10 ng CfGV at similar probe concentrations. Cross reactions were observed between LdNPV DNA probes and CfNPV. Multiple probing of membranes blotted with insect macerates was capable of diagnosing the presence of NPV and GV on membranes. This procedure appears to be useful in the diagnosis of large numbers of insects for several baculoviruses.