Physalis angulata as a Local Lesion Host for Postharvest Indexing of Potato Virus A. R. P. Singh, Research Scientist, Agriculture Canada, Research Station, P.O. Box 20280, Fredericton, New Brunswick, Canada E3B 4Z7. Plant Dis. 66:1051-1052. Accepted for publication 23 February 1982. Copyright 1982 Department of Agriculture, Government of Canada. DOI: 10.1094/PD-66-1051.

Physalis angulata was the best local lesion host for potato virus A (PVA) of three Physalis species tested. It grows rapidly, has long, smooth leaves, produces few branches, and remains susceptible to PVA up to flowering and beyond. Local lesions developed in 7–10 days on intact leaves and in 4–5 days on detached leaves. Potato viruses X, Y, and M did not cause local necrotic lesions in P. angulata. However, potato virus X caused systemic mottling, and potato virus Y caused mild to severe mosaic and leaf drop. The local lesions produced by inoculation with PVA singly and in combination with each of the other viruses (M, X, Y) were very distinct and unaffected by the presence of the other viruses. Local lesions were produced at a temperature range of 15 to 25 C and at a light intensity range of 4 to 10 klux. Crude extract in glycine-phosphate buffer from various parts of the PVA-infected tubers caused lesions in P. angulata. PVA was detected in field-grown tubers either freshly harvested or stored for 1–3 mo at 10 or 25 C. The use of P. angulata as a local lesion host was as effective as enzyme-linked immunosorbent assay in detecting PVA in mixed infections.

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