Vol. 10, Issue 12 (2021)

Author(s):
Arpitha HC, T Selvakumar, R Karthikeyan, C Bharathi and S Geethanjali

Abstract:
The field experiment was conducted during kharif 2021 at Oilseeds Farm of Agricultural College and Research Institute, Coimbatore. The experiment with 15 treatment combinations was laid out in split plot design with three replications. Main plot constitutes three irrigation methods (M₁: Surface, M₂: Drip and M₃: Rain hose) and subplot comprised of five weed management practices (S₁: Pre-emergence fb Hand weeding + Earthing up, S₂: Pre-emergence fb Post emergence fb Earthing up, S₃: Pre-emergence fb Post emergence fb Post emergence, S₄: Post emergence fb Post emergence fb Earthing up and S₅: Hand weeding fb Hand weeding + Earthing up). Groundnut variety Co 7 was used as a test crop. The results revealed that irrigation provided through drip system recorded lower weed dry matter and showed a higher weed control efficiency in combination of pre-emergence (pendimethalin @ 1.0 lit ha^-1) fb post emergence (imazethapyr @ 75 g a.i. ha^-1 + quizalofop-ethyl @ 50 g a.i. ha^-1) fb earthing up which was followed by rain hose irrigation with pre and post emergence herbicide spray over surface method of irrigation. Nutrient removal by weeds was reduced in herbicide sprayed treatments over hand weeding until critical weed period of 40 DAS. Hence, the irrigation methods and weed management practices significantly influenced on weed dry matter production, weed control efficiency and nutrient removal by weeds.