Effect of herbicides on soil microcosm, nodulation and yield in chickpea (Cicer arietinum L.)

Abstract

Herbicides are commonly used in kalaburagi to control weeds in chickpea. In addition to their impact on weeds, these herbicides are also affecting soil microorganisms which are responsible for numerous biological processes essential for crop production. In the present study, we assessed the impact of five commonly used herbicides three are pre emergence and two are post emergence [Pendimethalin (PRE), Chlormuron ethyl (PRE), Oxyfluorfen (PRE), Quizalofop ethyl (POE) and Phenaxoprop ethyl (POE)] on soil microbial populations in chickpea cultivation experimental plots. Our study showed that the herbicide treatments sinhibited the development of microbial populations in the soil, and the degree of inhibition closely related to the mode application as pre emergence or post emergence and varied with the types of herbicide. Weed free check recorded the highest number of microorganisms at all the different growth stages and differed in herbicides treated plots. Among the pre emergence pendimethalin recorded highest and in post emergence herbicides phenaxoprop ethyl resulted more in different stages of chickpea sampling. The study suggests that the herbicide application to soil of chickpea cultivation cause transient impacts on microbial population growth, when applied at recommended field application rate.