The Effect of Sulphur, Lambda-Cyhalothrin (pyrethroid) and Pendimethalin (dinitroaniline) Pesticides on Agricultural Soil Bacteria

Effect of Pesticides on soil bacteria

Abstract

Application of synthetic pesticides is the need of modern era to attain food production and  food demands of the increasing population. Pesticides kill, destroy or repel the target organism which includes pests and unwanted growth that affects the agricultural productivity but the knowledge of their effect on non target organisms including soil bacteria is important to control environmental disturbance. To check the effect of pesticides on soil bacteria a laboratory experiment was conducted where top soil samples collected from agricultural fields of Kasur district were sprayed with pesticides (Sulphur, Lambda Cyhalothrin and Pendimethalin), at recommended reference doses (RfD), 2RfD, 4RfD and 8RfD under normal environmental conditions. Afterwards, Microbial analysis was done at the end of each subsequent week for up to four weeks. Serially diluted soil samples were plated on Nutrient Agar media and incubated at 37 ⁰C for 24 hours. Number of bacteria was calculated by standard plate count method and results were statistically analyzed. The results revealed that Sulphur pesticides enhanced the bacterial population as compared to Lambda Cyhalothrin and Pendimethalin ones that suppressed the bacterial population when applied at RfD for a given period of time. It was concluded from the current study that the usage of synthetic agricultural pesticides should be minimized, moreover, when required only RfD of certain pesticide should be applied.