Effect of Novaluron Pesticide on Phosphatase Activity in Black Clay and Red Sandy Ground Nut (Arachis hypogaea L.) Soils

Biocatalysts have a vital role in all the biological activities. They show maximum influence in all the soil ecological reactions. Agricultural soils were frequently subjected with pesticides to control the pests. To get a better yield of agriculture food, better agriculture soil should be used for cultivation. The study was designed to determine the effect of novaluron pesticide used now a day for the pest control, on phosphatase activity. Soil samples collected from groundnut cultivating fields at Anantapur District, Andhra Pradesh randomly from a depth of 12cms. Air dried and sieved soil samples were taken and a laboratory experiment was conducted to investigate the effects of pesticides at their recommended field rates and higher rates on phosphatase activity in both soil samples after 10, 20, 30 and 40 days exposure under controlled conditions. Lower stimulatory activity is noticed at 10 days interval of time and striking stimulatory activity is noticed at 2.5 kg ha?', persists for 20 days in both soils. The higher concentration of the novaluron (5.0 - 10.0 kg ha?') were toxic to the enzymatic activity. The results of the present study clearly indicate that the field application rates show no effect on enzyme activity for longer period of incubation (40 days). But higher concentration (10 kg ha?') of pesticide leads to the inhibition of the enzymatic activity.