Management of Noxious Weed Johnson Grass (Sorghum halepense) in Sorghum under Semi-arid Region of Rajasthan, India
Shweta Gupta
*
Department of Agronomy, Rajasthan Agricultural Research Institute, Sri Karan Narendra Agriculture University, Rajasthan, 302018, India.
Surendra Singh
Department of Agronomy, Rajasthan Agricultural Research Institute, Sri Karan Narendra Agriculture University, Rajasthan, 302018, India.
Seema Sharma
Department of Agronomy, Rajasthan Agricultural Research Institute, Sri Karan Narendra Agriculture University, Rajasthan, 302018, India.
Ram Niwas Choudhary
Department of Agronomy, Rajasthan Agricultural Research Institute, Sri Karan Narendra Agriculture University, Rajasthan, 302018, India.
Pratibha Singh
Department of Agronomy, Rajasthan Agricultural Research Institute, Sri Karan Narendra Agriculture University, Rajasthan, 302018, India.
Bheem Pareek
Department of Agronomy, Rajasthan Agricultural Research Institute, Sri Karan Narendra Agriculture University, Rajasthan, 302018, India.
Anju Ghasil
Department of Agronomy, Rajasthan Agricultural Research Institute, Sri Karan Narendra Agriculture University, Rajasthan, 302018, India.
Kavita Bhadu
Department of Agronomy, Rajasthan Agricultural Research Institute, Sri Karan Narendra Agriculture University, Rajasthan, 302018, India.
Rahul
Department of Agronomy, Rajasthan Agricultural Research Institute, Sri Karan Narendra Agriculture University, Rajasthan, 302018, India.
*Author to whom correspondence should be addressed.
Abstract
A three-year field experiment was conducted during the kharif seasons of 2018–2020 in farmers’ fields within agro-climatic zone IIIA of Rajasthan, India, to evaluate post-emergence herbicides for managing Sorghum halepense in sorghum. Five treatments were arranged in a randomised block design with four replications: weedy check, quizalofop-ethyl at 70 g a.i. ha⁻¹, tembotrione at 100 g a.i. ha⁻¹, fluazifop-P-butyl at 200 g a.i. ha⁻¹, and a weed-free treatment. Herbicides were applied at 15–20 days after sowing, and weed density, weed-control efficiency, weed index, grain yield, stover yield, net return, and B:C ratio were assessed. Among the herbicide treatments, tembotrione at 100 g a.i. ha⁻¹ produced the lowest mean S. halepense density at 30 days after sowing and the highest mean weed-control efficiency of 71.39%. It also recorded the lowest weed index of 4.67. The weed-free treatment produced the highest grain and stover yields; however, these yields were statistically at par with those obtained using tembotrione. Tembotrione generated the highest net return of ₹31,312 ha⁻¹ and a B:C ratio of 1.44, exceeding the economic performance of the weed-free treatment. Quizalofop-ethyl and fluazifop-P-butyl caused phytotoxicity in sorghum. Under the conditions of this study, post-emergence application of tembotrione at 100 g a.i. ha⁻¹ provided the most favourable combination of Johnsongrass suppression, crop yield, and economic return among the evaluated herbicide treatments.
Keywords: Sorghum bicolor, Sorghum halepense, Johnsongrass, tembotrione, quizalofop-ethyl, fluazifop-P-butyl, post-emergence herbicide, weed-control efficiency, crop phytotoxicity