ARS | Publication request: IRIDOVIRUS INFECTION AND TOPICAL APPLICATION IN WHITEFLY.

Submitted to: Proceedings of Florida State Horticultural Society
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: July 11, 2001
Publication Date: January 2, 2001
Citation: Mckenzie, C.L., Hunter, W.B., Lapointe, S.L., Dang, P.M. Iridovirus infection and topical application in whitefly.. Proceedings of Florida State Horticultural Society. 2001. v. 114. p. 64-67.

Interpretive Summary: Crop damage caused by Bemisia exceeded $500 million in 1991 and resulted in almost 10,000 lost jobs in the U.S. Damage to Florida crops alone caused by direct feeding and more importantly as vectors of geminiviruses resulted in economic losses of $141 million. Few microbial bio-control agents and no known viral agents are available for use on whiteflies. A newly described entomopathogenic virus was recently discovered in south Florida whitefly populations. The virus was determined to be an iridovirus by DNA analysis. These viruses are known to be pathogenic to insects including whiteflies. Demonstrated modes of transmission for iridovirus in other insect systems have been shown to be through oral ingestion, cuticular wounding (abrasions), and occasionally sexual transmission. We confirmed whitefly infection with IIV-6 through oral ingestion via sucrose parafilm feeding chamber experiments and PCR analysis. Traditionally many biological agents are applied by foliar spray application; therefore, we also wanted to determine if this would be a feasible method of application of iridovirus to control whiteflies on tomatoes. Spray applications were inconclusive. Results and the potential use of entomopathogenic viruses as biological control agents are discussed.

Technical Abstract: Few microbial bio-control agents and no known viral agents are commercially available for use on whiteflies. A newly described entomopathogenic virus was recently discovered in south Florida whitefly populations and was determined to be an iridovirus by DNA analysis. Invertebrate iridescent virus 6 (IIV-6) is known to be pathogenic to insects including whiteflies. Demonstrated modes of transmission for iridovirus in other insect systems have been shown to be through oral ingestion, cuticular wounding (abrasions) and occasionally sexually transmitted. We confirmed adult whitefly infection with IIV-6 through oral ingestion via sucrose parafilm feeding chamber experiments and PCR analysis. Traditionally, many biological agents are applied by foliar spray application; therefore, we attempted to determine if this would be a feasible method of application of iridovirus to control whiteflies on tomatoes. Spray applications were inconclusive. Results and the potentia use of entomopathogenic viruses as biological control agents are discussed.