Improved detection of potato leafroll virus in plant material and in aphids.

To improve detection of potato leafroll virus (PLRV) in plant material and viruliferous aphids, the enzyme-linked immunosorbent assay (ELISA) was modified by simultaneous incubation of sample and conjugate (cocktail ELISA) and by amplification of the enzyme reaction. Using this technique, 50-100 pg of PLRV could be detected per sample, and the virus could be detected in highly diluted leaf sap and in single Myzus persicae nymphs after a 12-hr acquisition access period on PLRV-infected Physalis floridana plants. In addition, when coated plates were used, the total assay time for PLRV detection in plant material could be reduced to 20 min