Mineral Oil Inhibition of White Apple Leafhopper (Homoptera: Cicadellidae) Oviposition

Various rates, types and residue ages of horticultural mineral oils were tested for inhibition of oviposition by white apple leafhopper, Typhlocyba pomaria McAtee, in laboratory bioassays. The numbers of nymphs produced from females exposed to treated apple leaf surfaces were used to determine the behavioral effect. No differences in effect were found among the three oils tested (Orchex 796, Orchex 692, and Orchex 892). Inhibition of oviposition was found in concentrations of Orchex 796 as low as 1% vol:vol (2-fold reduction in nymphs), with complete inhibition at 4%. The inhibitory effect of this material at 1% vol:vol persisted for at least 3 d, with no difference between the 7-d-old residues and the check.