Use of allelopathic crop water extracts for reducing isoproturon and phenoxaprop-p-ethyl dose in Wheat

Mehboob Elahi, Zahid Ata Cheema, Shahzad Maqsood Ahmed Basra, Qurban Ali

Abstract
A field study was conducted at Agronomic Research Farm, University of Agriculture Faisalabad, Pakistan to investigate the possible reduction of phenoxaprop-p-ethyl and isoproturon dose in combination with four allelopathic crop water extracts (sorghum, sunflower, rice and Brassica) for weed control in wheat. The experiment was laid out in randomized complete block design (RCBD) with four replications. Water extracts of sorghum, sunflower, rice and brassica were tank mixed each @ 12 l ha-1 with each other and also with reduced rates of phenoxaprop-p-ethyl (287 g ha-1) and isoproturon (333 g ha-1). Both herbicides at rates (862 g ha-1 and 1000 g ha-1 respectively) were used as standard treatments. Result revealed that weed dry matter production by sorgaab, sunflower and rice water extracts with one third dose of isoproturon was 92% and 93% at 40 and 70 DAS. Which was superior (61% and 62% at 40 and 70 DAS) to the lable dose of phenoxaprop-p-ethyl and increased grain yield by 23% as weel as it was economical giving higher net returns and percent marginal returns whereas an other economical treatment was isoproturon @ 1000 g ha-1 which gave 93% reduction in weed dry weight and 30% increase in grain yield.

Key words: Allelopathy, Wheat, Sorgaab, Sunflower, Rice, Brassica, Phenoxaprop-p-ethyl, Isoproturon, weeds