Weed Menace and Post Emergence Herbicide Solution for Sustainable Maize Production in India

Abstract

Maize mostly cultivated in tropical conditions suffers from various biotic and abiotic stresses. Granted, while crop improvement has led to less disease and pest losses due to host plant resistance in maize hybrids, these factors still cause substantial yield losses of maize in India. In the event of incessant rains and unavailability of herbicides, farmers are not able to control weeds through pre-emergence herbicides and manual weeding. Such circumstances, compounded by escalating labor prices, demand effective post-emergence herbicide to manage weeds for sustainable and profitable maize production. To find effective post-emergence herbicides, field experiments were conducted at 20 locations in various agro-ecologies of India for three consecutive years (2015-2017). It was found that weeds caused 32.1 to 59.4% grain yield losses of hybrid maize in the kharif season in India. The losses from the weed in absence of weed management in hybrid maize were maximum in Central Western Zone (55.4 to 60.8%), followed by Northern Hill Zone (43.0 to 49.4%), North Western Plain Zone (44.1 to 49.1%), North Eastern Plain Zone (36.4 to 48.8%); and least in Peninsular zone (26.9 to 40.3%). These losses indicate that the rainfed ecosystem has the maximum yield reduction in kharif maize in central and northern India. The application of Atrazine (1.5kg a.i./ha) as pre-emergence followed by Tembotrione (120ml a.i./ha) at 25 DAS as post-emergence gave the best weed control and higher yield as well as net returns compared to the other pre- and post-emergence herbicide-based management practices at most of the locations. The study suggests that the Tembotrione at 120 ml a.i./ha at 25 DAS could be a better option for weed management in maize in India and similar agro-ecologies.