Formulations with 1% soybean oil ? 108 conidia mL-1 (F = 12.77; df = 4.3; P = 0.0001 for nymphs; F = 17.73; df = 4.3; P = 0.0001 for adults), 10% soybean oil ? 107 conidia mL-1 (F = 11.34; df = 4.3; P = 0.0001 for nymphs; F = 15.6; df = 4.3; P = 0.0001 for adults) and 108 conidia mL-1 (F = 4.2; df = 4.3; P = 0.511 for nymphs; F = 14.31; df = 4.3; P = 0.0001 for adults) provided similar performance for both insect stages.