COMPARISON OF A DNA-DNA DOT-BLOT HYBRIDIZATION ASSAY WITH LIGHT-MICROSCOPY AND RADIOIMMUNOASSAY FOR THE DETECTION OF A NUCLEAR POLYHEDROSIS-VIRUS

A dot-blot hydridization assay was developed for the detection of a nuclear polyhedrosis virus (NPV) and was compared to light microscopy and radioimmunoassay (RIA). Using cloned NPV DNA labelled with 32P as a probe, a number of hybridisation assay procedures was examined. The assay was found to be more sensitive than differential staining, phase-contrast microscopy, or indirect solid-phase RIA with as few as 20 occlusion bodies (150 pg DNA) being detected. Samples do not require prior purification or DNA extraction. The assay was shown to be specific for NPV and has the potential to detect and discriminate between strains of the virus. With little modification the assay may be used to detect other insect viruses.