Response of foliar application of KNO 3 on yield, yield components and lint quality of cotton (Gossypium hirsutum L.)

Abstract

Effect of potassium on fiber quality characteristics and nitrogen on vegetative growth tends to be more critical when deficiency is expected in a field. Foliar applications of potassium may be used to supplement soil applications to maximize yields and improve quality of cotton. A cotton variety NIAB-111 was sown at Crop Physiology Research area, University of Agriculture, Faisalabad to check the effect of KNO3. Four different levels of KNO3 were applied with a control and water in foliar applications varying the number of applications on different stages. The crop was sown in a randomized complete block design with split plot arrangement and was replicated thrice to observe the effect of potassium on growth yield and fiber quality of cotton. Plant height, biomass, number of bolls, number of leaves per plant and all fibre quality parameters were significantly affected by increasing concentrations of foliar potassium. In most of the cases, spraying 2% foliar potassium gave significant results. As number of leaves, number of sympodial branches, number of bolls, plant biomass, Ginning out turn (GOT%), fibre micronaire, fibre uniformity, fibre length and fibre strength were significant at 2% application of foliar potassium. But in case of boll weight, 2% spray of foliar potassium was dominated by 1.5% spray of foliar potassium. In some cases, like number of leaves, number of sympodial branches per plant, fibre strength, micronaire, fibre sci, fibre uniformity and ginning out turn, both concentrations 1.5 and 2% had statistically similar effects. Key words: Potassium nitrate, foliar application, growth, yield, lint quality, cotton.