Effect of Gypsum and Compost on Growth and Yield of Washington Navel Orange under Saline-Sodic Soils

Document Type : Original Article


1 Faculty of Agriculture, Seberbay Campus, 31527 Tanta, Egypt.

2 Soil and Water Department, Faculty of Agriculture, Tanta University, Egypt.


INCREASING saline-sodic soils area as a result of climatic change, wrong agriculture practices and unsuitable of nutrition sources were lead to malnutrition and caused low productivity and quality of citrus. The study focused on gypsum and compost application in the proper rates for coping with such variable parameters. The trial carried out during 2017 and 2018 seasons on Washington navel orange trees (Citrus sinensis L., Osbek) grafted on sour orange (Citrus aurantium L.). Six application treatments were examined for the purpose of the study, i.e., T1: control, T2: compost at 10 tons
/ fed, T3: compost at 15 tons/ fed, T4: gypsum at 10 tons/ fed, T5: T4+T2 and T6: T4+T3. Field capacity (FC), Permanent wilting point (PWP), available water (AW), soil moisture and soil total content of NPK as indicators of soil parameter for application treatments were looked up. Growth parameters such shoot length, number of shoots/branch, number of leaves/shoot and leaf area, yield attributes such fruit set, fruit cracking, peel thickness, total tree yield (Kg), fruit juice volume, TSS, acidity, total sugars and vitamin C and leaf nutritional content of N, P, K, Ca and Mg were also determined. Results showed that T6 gave the highest results followed by T5, T4, T3 and T2 whereas T1 was the lowest ones for all parameters under investigations.  The study aimed and recommends gypsum at 10 tons/ fed + compost at 15 tons/ fed for ameliorating saline-sodic soil and improving growth, yield and quality of Washington navel orange under such conditions.