Study of the Effects of Compost and Nitrogen on Concentrations of Nutrients in Citrange Seedlings

Abstract

A one-year factorial experiment using the randomized complete block design with three replications was carried out to study the effects of compost and nitrogen on the concentrations of nutrients in citrange seedlings. The treatments included various levels of the organic matter compost (zero, 2.5, 5, and 7.5%) and different levels of pure nitrogen from ammonium sulfate (zero, 20, 40, and 80 mg/kg soil). In all, 48 treatments were applied on citrange stocks. Comparison of mean squares for the effects of compost and nitrogen fertilizer on micronutrients showed that these effects were significant on potassium and manganese at the five percent probability level (and on iron, zinc, and copper at the one percent probability level), but were not significant on elements such as nitrogen, phosphorous, or magnesium, in citrange rootstocks. The maximum nitrogen and potassium concentrations in citrange leaves (2.90 and 1.83%, respectively) were achieved in the treatment of applying 7.5% compost with no nitrogen fertilizer. The highest phosphorous concentration in citrange leaves (0.80%) was observed in the treatment of applying 2.5% compost with no nitrogen fertilizer. The maximum potassium concentration in citrange leaves in the treatment of applying 7.5% compost and 40 mg/kg nitrogen was 0.74%. The highest iron and zinc concentrations in citrange leaves (201.4 mg/kg and 16.32 mg/kg, respectively) were achieved by the application of 2.5% compost and 40 mg/kg of the nitrogen fertilizer. The maximum potassium concentration in citrange leaves by applying 7.5% compost and 80 mg/kg of the nitrogen fertilizer was 32.35 mg/kg.The highest copper concentration in citrange leaves by the application of 5% compost with no nitrogen fertilizer was 15.24 mg/kg.