IMPACT OF FOLIAR APPLICATION OF POTASSIUM SULPHATE ON WEED DYNAMICS AND SOME PHYSIOLOGICAL ATTRIBUTES OF RAINFED BREAD WHEAT

Abstract

An experiment to find out the wheat growth as affected by foliar application of potassium Sulphate (K₂SO₄) on different growth stages under rainfed conditions was conducted at the Agricultural Research Institute, Dera Ismail Khan, Pakistan. Potassium doses viz. 0, 12, 18, 24, 30 and 60 kg ha^-1 were applied in foliar form at tillering, booting and heading stages of wheat. The course of study revealed that foliar application of K₂O in booting stage produced maximum leaf area index (LAI), leaf area duration (LAD), crop growth rate (CGR), net photosynthesis rate (NPR) and grain yield, while its application at heading stage produced maximum net assimilation rate (NAR). Among different doses, the application of potassium at the rate of 60 kg ha^-1 potassium at the rate of 60 kg  ha^-1 produced maximum growth and yield and its components during two consecutive cropping seasons of wheat crop while weed density (m^-2), relative weed density (%), fresh weed biomass (g m^-2) and dry weed biomass (g m^-2) influenced non-significantly for both the years. These findings suggest that foliar application of potassium sulphate @ 60 kg ha^-1 along with recommended dose of nitrogen (120 kg ha^-1) and phosphorus (90 kg ha^-1) is the most suitable for successful wheat production under rainfed conditions.