Growth Stimulation, Metabolic Activities and Fruit Yield of Tomato as Influenced by Fulvic Acid

A pot experiment was conducted at Land Resources Research Institute, National Agricultural Research Centre (NARC), Islamabad during spring 2012 to study the effect of foliar applied fulvic acid (FA) on tomato grown under greenhouse conditions. Six kg sandy loam soil (Nabipur series mixed hyperthermic Udic Ustochrept) filled in plastic pot and grown with tomato plants (Riogrande). Basal dose of N, P, K, along with Zn, Fe, and B were applied @ 200, 150, 200, 10, 2 and 1 mg/kg soil FA was applied as foliar @ 0, 150, 300, 450 and 600 mg/l respectively. Results showed a significant increase in fruit yield, harvest index and other agronomic parameters with FA application. Besides macronutrients plant micronutrient concentration also increased with FA application which could be ascribed to stimulating effect of FA on enhanced biomass. Protein and chlorophyll contents of leaves also significantly changed with applied FA. Based on the results of the study it could be concluded that FA spray at 150 and 300 mg/ l were appropriate dose for maximum nutrient uptake by plant for optimum growth and maximize yield.