The toxicity of selected commercial formulations of neem on Tetranychus urticae Koch (Acari: Tetranychidae) and two predatory mites Euseius alatus De Leon and Phytoseiulus macropilis (Banks) was studied. Topical toxicity was tested with the commercial formulations (Natuneem, Neemseto and Callneem) and extract of neem's seeds at concentration 1%, compared to the standard acaricide abamectin at concentration of 0.3 ml/L and the control treatment (distilled water). Based on the best performance against T. urticae through topical contact, the formulation Neemseto was selected to be evaluated using different concentrations against eggs, and residual and repellent effects on adults of the mites. Egg treatment consisted of dipping eggs into Neemseto dilutions and control treatment for five seconds. In addition, residual and repellent effects of Neemseto for adult mites consisted of using leaf discs dipped into the dilutions for five seconds. The toxicity of Neemseto on eggs and adults was greater for T. urticae compared to the toxicity observed for the predatory mites. Neemseto was repellent for T. urticae and E. alatus when tested at the concentrations of 0.25, 0.50 and 1.0%, and did not affect P. macropilis. Neemseto using all concentrations, while for the predatory mites significant reduction of mite fecundity was only observed at the largest concentrations reduced the fecundity of T. urticae significantly. So Neemseto, among tested neem formulations, performed better against the twospotted spider mite and exhibited relatively low impact against the predatory mites studied.

RESUMOA toxicidade de diferentes concentrações de Natuneem a Tetranychus urticae Koch e a dois ácaros predadores, Euseius alatus De Leon e Phytoseiulus macropilis (Banks), foi estudada. Foi avaliada a toxicidade sobre ovos, e o efeito residual e repelente, sobre adultos. O tratamento dos ovos consistiu na imersão em diluições de Natuneem por cinco segundos, e o efeito residual e repelente sobre adultos consistiu na imersão de discos de folhas de Canavalia ensiformes (L.) DC. também em diluições por cinco segundos. Natuneem foi repelente para T. urticae e E. alatus, quando testado nas concentrações de 0,25; 0,50 e 1,00%, e exibiu efeito neutro para P. macropilis. A toxicidade de Natuneem a ovos e adultos foi maior para T. urticae comparada à toxicidade observada para os ácaros predadores. A fecundidade de T. urticae foi reduzida significativamente por Natuneem em todas as concentrações, enquanto para os ácaros predadores a redução foi significante apenas nas maiores concentrações. Natuneem, nas concentrações testadas, apresentou melhor ação sobre o ácaro-rajado e menor impacto para os ácaros predadores.Termos para indexação: Azadiractina, controle, ácaro-rajado, fitoseídeos. ABSTRACTThe toxicity of the Natuneem at different concentrations for both Tetranychus urticae Koch and two predatory mites Euseius alatus De Leon and Phytoseiulus macropilis (Banks) were studied. The toxicity on eggs, and the residual and repellent effects on adults was evaluated. Egg treatment consisted on dipping eggs into Natuneem dilutions for five seconds; and residual and repellent effects for adults consisted on dipping leaf discs of Canavalia ensiformes (L.) DC. into the dilutions for five seconds. Natuneem was repellent for T. urticae and E. alatus at the concentrations 0.25, 0.50 and 1.0%, and exhibited neutral effect on P. macropilis. The toxicity of Natuneem on eggs and adults was greater for T. urticae compared to the toxicity on predatory mites. The fecundity of T. urticae was reduced significantly by Natuneem in all concentration. On predatory mites significant reduction on its fecundity was found at the highest concentrations evaluated. Natuneem was performed better against the twospotted spider mite and exhibited relatively low impact against the predatory mites under the conditions studied.