Sequential herbicidal application on weed community and yield of wheat Sumitra Gugulothu1,*, Rajkumara S.1, Lamani Kumar D.2 1College of Agriculture, University of Agricultural Sciences, Dharwad, Karnataka580005, India 2AICRP on Wheat and Barley, MARS, University of Agricultural Sciences, Dharwad, Karnataka580005, India *Corresponding author email: gugulothusumitra@gmail.com
Online Published on 28 October, 2024. Abstract Effect of time, dosage of herbicide and crop residue were evaluated in Dharwad (Karnataka) on weed flora in wheat during winter (Rabi) season of 2020-21 and 2021-22. The experiment used a factorial randomized block design with twelve treatments, including a randomized complete block design to compare controls with treatment combinations. Results revealed that pre-emergence of pendimethalin reduced the number of grasses (3.0/m2), sedges (1.7/m2), broad-leaved weeds (4.5/m2) and total number of weeds (9.2/m2) at 20 DAS. At 40 and 60 DAS, sequential application of pre-emergence followed by post-emergence reduced the grasses (2.9 and 5.9/m2), sedges (1.1 and 1.5/m2), broad-leaved weeds (3.1 and 3.5/m2), total number of weeds (6.8 and 10.6/m2) and dry weight of weeds (1.9 and 3.4 g/m2). Among the dosage, 100% recommended dose of herbicide (RDH) recorded lower grasses, sedges, broad-leaved weeds and dry weight of weeds compared to 75% RDH. Weed population did not differ significantly with application of soybean residue and no residue treatment. Pre-emergence followed by post-emergence at 100% RDH with soybean residue recorded higher grain yield (4.17 t/ha), weed control efficiency (79.7, 92.1 and 84.5%) and lower weed index (4.5%) compared to rest of the treatments. Lower grain yield (2.98 t/ha) and weed control efficiency (65.9, 56.6 and 42.7%) were with pre-emergence at 75% RDH without soybean residue. The results suggested that pre-emergence followed by post-emergence with 100% RDH with soybean residue was the best broad spectrum effective herbicide in order to minimize the diverse weed flora in wheat. Top Keywords 100% RDH, Pre-emergence, Post-emergence, Sequential herbicide, Soybean residue. Top |