Field study on the efficacies of some safer pesticides to control Eotetranychus orientalis (Acari: Tetranychiidae) in urban green landscape of Ahvaz

The oriental spider mite, Eutetranychus orientalis Klein (Acari: Tetranychidae), is an important pest of Indian siris and some other trees in Ahvaz’s green landscape. By feeding on the Indian siris leaves, this pest causes leaf fall, reducing the aesthetic and green surface and its resistance to other potential pests and diseases. One of the important strategies to control the pest is application of acaricides. The choosing the efficient and safer acaricides plays critical role considering the daily contact of a large number of citizens with the urban green space. In this research, the short-term and long-term effectiveness of four pesticides abamectin, Palizin®, etoxazole, and Nimazal® which are all low-risk pesticides for humans and mammals, at concentrations 0.5, 2, 0.5, and 1 (L/1000 L), were evaluated to control the pest mite population in a field study, respectively. For this purpose, the population of nymphs and adults of this mite was recorded on the treated trees 1 day before, 2, 7, 14, and 21 days after treatment and statistically compared with the control treatment where the trees were treated only with water. This study showed that abamectin and etoxazole had very favorable short-term and long-term effects on E. orientalis population. Although Palizin® led to the control of the pest in the short term, it did not have a favorable long-term protective effect, and as a result, the treatment of trees has to be repeated in order to properly control the pest. Nimazal® also showed its effect with two to three weeks lag time and this effect was relatively lower than abamectin and etoxazole.