Toxicity of purified fungal toxin hirsutellin A to the citrus rust mite phyllocoptruta oleivora (Ash.)
A toxic protein, hirsutellin A, isolated from culture filtrate during liquid fermentation of the fungal mycelia of Hirsutella thompsonii, was tested using contact/residual and residual leaf bioassay methodologies at concentrations of 0, 10, 32, 56, and 100 &mgr;g/ml against adult citrus rust mite, Phyllocoptruta oleivora. P. oleivora is the natural host of the parasitic fungus, H. thompsonii. Mite mortality increased with an increase in hirsutellin A concentration, reaching virtually 100% at 100 &mgr;g/ml using both leaf assay methods. The number of eggs found on leaf disk bioassays within a 3-day period decreased significantly with an increase in hirsutellin A concentration, suggesting that fecundity was affected prior to the death of the host. Copyright 1998 Academic Press.
Institute of Food and Agricultural Sciences, University of Florida, 700 Experiment Station Road, Lake Alfred, Florida, 33850, USA.
C
Omoto
CW
McCoy