Effect of Different Application Rates of Pesticides on Groundnut (Arachis hypogaea L.): A Study on Indian Soils

Chemical pesticides can cause a potential adverse effect on plants and other non-target organisms when environmental exposure conditions are vulnerable. This study was undertaken to determine the effect of pesticides, on amylase activity in two groundnuts (Arachis hypogaea L.) soils. The effect of pesticides was assessed throughout10, 20, 30 and 40 days for Amylase activity. Bifenthrin, Buprofezin, Dimethomorph and pyraclostrobin were selected because of their abundant usage in Indian agriculture to combat various insect pests of groundnut. Soil samples (red sandy loam and black clay soils) collected from groundnut (Arachis hypogaea L.) cultivated fields of Ananatapuramu District of Andhra Pradesh, India were treated with pesticides at different concentrations i.e. 10, 25, 50, 75 and 100 ppm, which are equivalent to field application rates (1.0, 2.5, 5.0, 7.5 and 10.0 kg ha-1) in the laboratory. Data were analysed using one-way ANOVA and the differences were contrasted using Duncan’s multiple range test (DMRT). The activity of Amylase was significantly more treated with pesticides at levels of 2.5 kg ha-1 in black and red soils respectively at 24 and 72hrs. But at higher concentrations of 7.5 and 10.0 kg ha-1 respectively, pesticides were toxic to amylase activity. The activity of amylase was drastically decreased with increasing periods of incubation up to 40 days. The results of the study indicate that pesticides profoundly enhanced the activity of amylase at 2.5 kg ha-1.