Effect of Potassium Fertilizer Application on Physiological Parameters and Yield of Cotton grown on a Potassium deficient Soil

A potassium fertilizer field trial was carried out on a coarse silty loamy soil, low in exchangeable K + in the Zhejiang Province (People's Republic of China). Potassium fertilizer applications increased the leaf area, the chlorophyll concentration, and the CO 2 assimilation of cotton grown on this K + deficient soil. Potassium increased the activity of the cytochrome oxidase and nitrate reductase, increased the stomatal conductance and decreased the transpiration. The leaf tissue of K + deficient plants was flaccid, the cuticle of leaves poorly developed and contrasted much with the leaves well supplied with K + which were characterized by a full turgor and a well developed cuticle. According to these physiological effects of K + , potassium fertilizer application increased lint yield and improved cotton and seed quality.