VIEW ARTICLE

Vector Relations

Effect of Beetle Regurgitant on Plant Virus Transmission Using the Gross Wounding Technique. J. Monis, Department of Plant Pathology, University of Arkansas, Fayetteville 72701; H. A. Scott(2), and R. C. Gergerich(3). (2)(3)Department of Plant Pathology, University of Arkansas, Fayetteville 72701. Phytopathology 76:808-811. Accepted for publication 27 February 1986. Copyright 1986 The American Phytopathological Society. DOI: 10.1094/Phyto-76-808.

Regurgitant from Mexican bean beetles and bean leaf beetles inhibited the transmission of zucchini yellow mosaic virus (ZYMV) not transmissible by beetles and common tobacco mosaic virus and had little or no effect on beetle-transmissible squash mosaic virus when mixed with purified virus preparations and inoculated to systemic hosts using the gross wounding technique. Transmission of the beetle-transmissible cowpea severe mosaic virus (CSMV) was unaffected by regurgitant when cowpea was used as the test plant. No transmission occurred, however, when bean was inoculated with a mixture of regurgitant and CSMV using the gross wounding technique. Two members of the bromovirus group, which are inefficiently transmitted by beetles, behaved differently when mixed with regurgitant and inoculated using the gross wounding technique. Brome mosaic virus was not inhibited, whereas cowpea chlorotic mottle virus (CCMV) showed the same pattern of inhibition as a virus not transmissible by beetles. Recovery of CCMV and ZYMV from virus:regurgitant mixtures by fractionation in CsCl gradients resulted in virus preparations that were infectious when inoculated to plants using the gross wounding technique. This demonstrates that viruses not transmissible by beetles and the inefficiently transmitted CCMV are not inactivated by beetle regurgitant.