​Efficacy of Pre and Post-emergence Herbicides for Weed Management in Groundnut

Abstract

Background: Herbicides are used in agriculture to reduce the density of weeds and improve the crop yield. Pendimethalin 30% EC is widely used pre-emergent herbicide to control annual grasses and certain broad leaf weeds; is no longer effective against established weeds like Cyperus and Commelina benghalensis, Acalypha indica and Phyllanthus spp. that are dominant in groundnut crop. Combination of Pendimethalin 30% and Imazethapyr 2% EC is a broad-spectrum herbicide that controls most broadleaf weeds and some annual grasses. The current study aimed to improve the profitability of farmers by effectively and economically by controlling the targeted weeds. Methods: A field experiment was conducted at Zonal Agricultural and Horticultural Research Station (ZAHRS), Babbur Farm, Hiriyur, Karnataka during Kharif 2018, 2019 and 2020, to study the efficacy of pre and post-emergence herbicides for weed management in groundnut. The trial comprised of nine treatments involving two pre-emergence herbicides (Pendimethalin 38.7 CS 1.0 kg/ha PE and Pendimethalin 30 EC+Imazethapyr 2 EC 1.0 kg/ha PE (ready mix)) alone and in combinations with post-emergence herbicides (quizalofop-p-ethyl 50 g/ha at 15-20 DAS (PoE)), along with pre-emergence herbicides super imposed with hand weeding at 30 DAS and compared with two inter cultural operation at 15 and 30 DAS followed by manual weeding for intra rows and weedy check. Result: The experimental results revealed that, among the different herbicides treatments, the higher net return (Rs. 92,835/ha) and B:C ratio (2.70) were noticed in Pendimethalin 30 EC+Imazethapyr 2 EC 1.0 kg/ha PE (ready mix)+manual weeding at 30 DAS as compared to control plot (Rs. 2620/ha and 0.96, respectively) this has effectively controlled most of the weed flora present in the experimental field.