Abstract

Activity of Amylase in Black Clay and Red Sandy Clay Soils as Influenced by Insecticide Interaction

Author(s): Madakka M, Sake Pradeep Kumar and Rangaswamy

Activity of amylase after application of insecticide combinations viz., profenofos + cypermethrin and deltamethrin + endosulfan at concentrations ranging from 0.0 to 10.0 kg ha-1 in black and red soils of groundnut were studied under laboratory conditions.Amylase activity was increased with increase in concentrations of insecticide combinations upto 5.0kg ha-1. Pronounced activity of amylase in terms of glucose formed from starch (2%) was observed at observed at 5.0 kg ha-1 of profenofos + cypermethrin and 2.5kg ha-1 of deltamethrin + endosulfan in both black and red soil. Higher levels of these were toxic to amylase activity. In soil samples receiving at 1.0 to 5.0kg ha-1 of insecticide combinations, the accumulation of glucose was significantly more at 20 days activity of enzyme decreased with increasing period of incubation. The increase was more striking when substrate was exposed to the soil sample for 72 hours of amylase enzyme activity. From obtained results it was concluded that the influence of the selected insecticide combinations on enzyme activity was dose dependent.