Limited field establishment of a weed biocontrol agent, Floracarus perrepae (Acariformes: Eriophyidae), against Old World climbing fern in Florida--a possible role of mite resistant plant genotypes.
The leaflet galling mite Floracarus perrepae Knihinicki & Boczek was released on Lygodium microphyllum (Cav.) in 63 plots in Florida from 2008 to 2009. Mites transferred onto field plants in 34 plots, but failed to establish populations in the majority of plots. Leaflet galls were  observed in only six plots, and in only two plots did mite populations persist for >12 mo. Rates of mite transfer onto field plants were similar for methods using direct transfer of galls versus approaches using passive transfer of mites from infested plants. Often leaflets on some L. microphyllum  plants were heavily galled by F. perrepae, whereas leaflets on intertwined stems of other L. microphyllum plants were ungalled but exhibited a characteristic browning and scorching of the leaflet tips. Living mites were consistently present on the undersurface of scorched leaflet tips on ungalled  plants, suggesting that this damage might be caused by mite feeding on L. microphyllum genotypes that did not support induction of leaflet galls. Plant nutritional status did not account for differences in galling response, because there were no differences in leaflet nitrogen between galled  and ungalled stems. We review those factors known to affect the colonization of biological control agents, and discuss how they may have contributed to the lower than expected rate of F. perrepae establishment.
USDA-Agricultural Research Service, Invasive Plant Research Laboratory, 3225 College Avenue, Fort Lauderdale, FL 33314, USA. anthony.boughton@ars.usda.gov
Anthony J
AJ
Boughton
Robert W
RW
Pemberton
D000818:Animals; D061046:Biological Control Agents; D005247:Feeding Behavior; D005260:Female; D029624:Ferns / Q000235:genetics* / Q000502:physiology; D005431:Florida; D005838:Genotype; D058865:Introduced Species; D008925:Mites / Q000502:physiology*; D010058:Oviposition; D010572:Pest Control, Biological; D018515:Plant Leaves / Q000235:genetics / Q000502:physiology; D010941:Plant Tumors; D012621:Seasons
D061046:Biological Control Agents