Efficacy of Acetamiprid Granule against Cotton Aphid on Cucumber Plants by Various Application Methods
The various efficacy of acetamiprid granule against the cotton aphid on cucumber plants according to several different applications such as planting hole and soil-surface applications was investigated. In planting hole application, the uncontrolled-release granule showed excellent efficacy when treated at the center of hole dug in soil as well as when treated uniformly in the hole. In case of soil-surface application, the efficacy of the granule exhibited higher activity against the aphid as the distance between the treated point and the foot of the transplanted seedling became shorter within the distance of 5, 10 and 20 cm from the foot of the seedling. The relationship between the efficacy and distance of treated points was the same as in the uncontrolled-release granule. Besides, the influence of the watering volume on the activity was examined. With planting hole application, the activity with lower watering-volume plots was higher than that with higher watering one within the watering volume designed. On the other hand, with soil-surface application the activity against the aphids was inferior to that with planting hole application. Moreover, the effect of watering volume and kind of soil on the activity of the controlled-release granule with planting hole application was examined. It was indicated that a relation between the efficacy and watering volume varied by the kind of soil. |