Effect of phosphorus levels on growth and chemical composition of the karonda (Carissa carandas L.) seedling growth in sand culture Singh Subhash Chandra, Ph.D. Scholar, Misra K.K., Professor and Head, Awasthi Priya, Ph.D. Scholar Department of Horticulture, College of Agriculture, Govind Ballabh Pant University of Agriculture and Technology, Pantnagar, Uttarakhand-263 145 Online published on 5 April, 2012. Abstract Symptoms of phosphorus deficiency were induced in sand culture under polyhouse condition to study the effect of phosphorus supply on growth and uptake of other macro and micro nutrients and to find out whether the leaf phosphorus concentration required for optimum growth of plants. Maximum value of height of seedling (28.83 cm), number of leaves per seedling (26.98), length (2.57 cm), breadth (1.70 cm) of leaf, fresh weight (0.075 g) and dry weight (0.0246 g) of leaf, leaf area per seedling (2.92 cm2), stem girth of seedling (0.301 cm) and length of primary root (19.81 cm) with treatment T5 (control) were registered whereas, minimum 12.80 cm, 15.75, 2.25 cm, 1.34 cm, 0.054 g, 0.0125 g, 2.75 cm2, 0.176 cm and 12.84 cm were recoded with T1 (without phosphorus). Maximum chlorophyll ‘a’ content (0.954 mg/g fresh weight) with T9 and minimum (0.672 mg/g fresh weight) with T1 was found. Chlorophyll ‘b’ and total chlorophyll content of leaf was found maximum 0.599 mg/g fresh weight with T7 and 1.817 mg/g fresh weight with T8 and minimum 0.342 mg/g fresh weight and 0.696 mg/g fresh weight with T1, respectively. Increasing phosphorus supply increased the leaf phosphorus content (0.45 per cent) with T9, however when phosphorus was omitted from the nutrient solution, the leaf copper content (55 ppm) and iron content (140 ppm) increased significantly. Other nutrients did not influence by variable phosphorus supply. For better plant growth and maximum production, the phosphorus level must be maintained in the range of 0.30–0.31 per cent. Top |