Brito Hilda M, Gondim Manoel G C, de Oliveira José V, da Câmara Cláudio A G
Depto. Agronomia, Univ. Federal Rural de Pernambuco, Rua Dom Manoel de Medeiros s/n, Recife, PE.
Neotrop Entomol. 2006 Jul-Aug;35(4):500-5. doi: 10.1590/s1519-566x2006000400012.
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.
研究了印楝几种选定商业配方对二斑叶螨科赫(蜱螨亚纲:叶螨科)以及两种捕食性螨类——翼钝绥螨德莱昂和大草蛉螨(班克斯)的毒性。用商业配方(印楝素、Neemseto和Callneem)以及浓度为1%的印楝种子提取物测试局部毒性,与浓度为0.3毫升/升的标准杀螨剂阿维菌素和对照处理(蒸馏水)进行比较。基于通过局部接触对二斑叶螨的最佳防治效果,选择Neemseto配方使用不同浓度来评估对卵的作用以及对螨类成虫的残留和驱避效果。卵处理是将卵浸入Neemseto稀释液和对照处理液中5秒钟。此外,Neemseto对成年螨的残留和驱避效果包括将叶盘浸入稀释液中5秒钟。与捕食性螨类相比,Neemseto对二斑叶螨的卵和成虫的毒性更大。当以0.25%、0.50%和1.0%的浓度进行测试时,Neemseto对二斑叶螨和翼钝绥螨具有驱避作用,而对大草蛉螨没有影响。Neemseto在所有浓度下都显著降低了二斑叶螨的繁殖力,而对于捕食性螨类,仅在最大浓度下才观察到螨类繁殖力的显著降低。因此,在测试的印楝配方中,Neemseto对二斑叶螨的防治效果更好,对所研究的捕食性螨类的影响相对较小。