Zinc Fertilization in Soil with the Application of Citric Acid and Extract of Some Plants on Growth and Biochemical Constituents of Tomato (Solanum lycopersicum L.)

Abstract

To study the effect of zinc fertilization with the applications of some plant extracts (Cannabis, Vernonia, and Parthenium spp.) and citric acid a field experiment was conducted. Growth (length, dry weight), some biochemical constituents (pigments and protein contents; and activity of catalase and peroxidase). The parameters of reproductive yield (size, number, and weight of fruit) were evaluated in test plants tomato (Solanum lycopersicum L.). Maximum promotory effects with respect to dry weight, pigments, and protein contents were observed at the ZnSO₄ application with citric acid in the soil, followed by the Parthenium extract (20%). Other plants (Vernonia and Cannabis) extracts (20%) and a single application of ZnSO₄ showed less promotory effects on the above parameters. Among the above plant extracts maximum positive effects, Parthenium extract (20%) was observed on dry weight (+45%), length (+ 39%), and protein content (+ 595%) in tomatoes.