The chemical Control of Two-spotted Spider Mite in Soybean Fields
Paper ID : 1171-IPCA4
Maryam Rezaie *1, Laleh Ebrahimi2, Mohammad Mobasheri3
1Zoology department
2Iranian Research Institute of Plant Protection
3Agricultural and Natural Resources Research Center
The two-spotted spider mite, Tetranychus urticae Koch is one of the most important pests of soybean fields. This study was conducted in soybean fields of Golestan and Ardabil provinces (Moghan). Treatments were, including clorfenapyr (Payton®) 36% SC 0.5 and 0.4 ml/L, propargite (Omite®) 57% EC 1 ml/L, bromopropylate (Neuron®) 25% EC 1 ml/L, hexythiazox (Nissorun®) 10% EC 0.75 ml/L and a control treatment by spraying water. Mean number of mites per leaf was counted one day before and 3, 7, 14, 21 and 28 days after spraying in three floors of plant (bottom, middle and top of plant). The percentage of efficiency was calculated by the Henderson-Tilton method. Statistical analyses were done using SAS softwares with randomized complete block design in multiple spaces. Clorfenapyr (Payton®) was effective after 3 days. The percent mortality of mites when were treated with clorfenapyr (0.5 ml/L) in the upper, lower and middle floors was 83-86% in Ardabil province, although has been reported 72-84% for Payton (0.4 ml/L). While in Golestan province, it has been 100%. The efficacy of the compound was 68-72% (0.4 ml/L) and 78-94% (0.5 ml/L) in Ardabil province (Moghan) and was 100% in Golestan province after 7 days. The efficacy of the compound was up to 99% (Ardabil province) and 96% Golestan province after 28 days that indicated the persistence of these acaricides. The number mites in lower floors of soybean were more than the upper and middle floors, but after the application of this pesticide was not significantly different. It is recommended to use chlorfenapyr due to high short-term effect (three days after spraying) and duration of action up to 28 days after spraying to control two-spotted spider mite in soybean fields. In most cases, the application of the two concentrations of the clorfenapyr was not significantly different, but the percent mortality was more when it treated with 0.4 ml/L. Based on these results, we recommend the 0.4 ml/L dose of clorfenapyr (Payton®) for the control of two-spotted spider mite in soybean fields.
: Acaricides, soybean, floor, two-spotted spider mite and efficacy.
Status : Abstract Accepted (Oral Presentation)