Herbicidal Potential of Organic Acids for the Management of Garden Land Weeds

Abstract

There is an increasing importance to eco-friendly alternatives in weed management in the current context of the shift towards sustainable forms of agriculture like organic and natural farming. The unscrupulous use of chemicals in agricultural practices has led to many adverse effects on ecology or the environment as well as the quality of food grown. Under this context, studies were conducted to evaluate herbicidal potential of organic acids as eco-friendly alternatives for weed management- acetic, lactic, and formic acids at four doses 2.5%, 5%, 10%, and 20% were used. A field experiment was conducted at the Agronomy farm, Kerala Agricultural University, Thrissur, using a factorial randomized block design with three replications. The acids were sprayed on three and six-week-old weeds, and the effect of these acids on weed, soil quality, and residual effect on cowpea seedlings was assessed. In three-week-old weeds, acetic and formic acid spray at 5%, 10%, and 20% achieved complete control without regrowth. Lactic acid at 10% and 20% also gave complete control. However, in six-weeks-old weeds, complete control of dicot weeds was achieved at 10% and 20% of formic and acetic acid and 20% of lactic acid. Monocots were comparatively more resilient; complete damage was possible only with 20% of acetic and formic acid, while lactic acid failed to provide complete control even at this concentration. Soil microbial population increased significantly upon spraying of organic acids. Cowpea raised immediately following organic acid spray showed no effect on germination and initial growth.