Frankliniella occidentalis can transmit impatiens necrotic spot tospovirus to peppermint
Studies have been carried out in Oregon, US, to demonstrate that Frankliniella occidentalis (EPPO A2 quarantine pest) is able to transmit impatiens necrotic spot tospovirus, as this transmission was simply assumed by the increasing occurrence of the disease in protected crops. The authors have shown that F. occidentalis can transmit a begonia isolate of impatiens necrotic spot tospovirus to peppermint (Mentha piperita cv. Black Mitcham), in glasshouse conditions. Adult thrips, 4, 6, 8 and 10 days after emergence were able to transmit the virus and higher rates were associated with the 8 days old adults, however adults of 2 days old were not able to transmit the virus. Detection (ELISA) of the virus in adult thrips was consistent with their ability to transmit the disease. On peppermint, symptoms of impatiens necrotic spot tospovirus include stunting, downward curling and leaf tip dieback, and occasional growing tip necrosis. Older leaves are bronze-coloured and exhibit sunken, brownish-grey lesions.
As in general, peppermint is a crop propagated under glasshouse and then planted in the field, the authors concluded that the behaviour of impatiens necrotic spot tospovirus and its transmission by thrips in the field still need to be studied.
Sources
DeAngelis, J.D., Sether, D.M. and Rossignol, P.A. (1994) Transmission of impatiens necrotic spot virus in peppermint by western flower thrips (Thysanoptera: Thripidae).
Journal of Economic Entomology, 87 (1), 197-201.