WEED CONTROL IN KENAF (Hibiscus cannabinus L.) THROUGH SEQUENTIAL APPLICATION OF PRE- AND POST- EMERGENCE HERBICIDES

Abstract

An experiment was conducted during April–September 2014 at Agronomy Field Laboratory, Bangladesh Agricultural University, Mymensingh to evaluate the effect of some pre and post emergence herbicides on weed control, kenaf growth and yield. Fourteen treatment combinations formed by three pre-emergence herbicides (Panida, Prechlor and Manage), three post emergence herbicides (Quilop, Pyzero and Whip Super), hand weeding along with weedy check and weed free check were included in the study. The treatments were: T₁ = Weedy check, T₂ = Weed free check, T₃ = Panida + hand weeding (HW), T₄ = Prechlor + HW, T₅ = Manage + HW, T₆ = Panida + Pyzero, T₇ = Prechlor + Pyzero, T₈ = Manage + Pyzero, T₉ = Panida + Quilop, T₁₀ = Prechlor + Quilop, T₁₁ = Manage + Quilop, T₁₂ = Panida + Whip Super, T₁₃ = Prechlor + Whip Super and T₁₄ = Manage + Whip Super. The experiment was laid out in a randomized complete block (RCB) design with three replications. The result revealed that the treatment T₁₃ (Prechlor + Whip Super) showed best control of weeds as reflected by lowest weed density and weed dry matter. This treatment (Prechlor @ 1.0 L ha⁻¹ in combination with Whip Super @ 650 mL ha⁻¹) gave the highest fibre and stick yields (3.55 and 7.59 t ha⁻¹, respectively) due to improvement of yield attributing characters. The study concluded that weeds in kenaf could be effectively controlled and the highest kenaf yield could be obtained by the applying a pre-emergence herbicide Prechlor @ 1.0 L ha⁻¹ at 3 days after sowing (DAS) followed by the post emergence application of Whip Super @ 650 mL ha⁻¹ at 25 days after sowing (DAS).