Behavior of some Micronutrients and Water Productivity in Rice Soil Under Irrigation Intervals and Organic and Inorganic Fertilizes

Abstract

A field experiment was carried out to investigate the effect of organic and inorganic fertilizers and their combinations under different irrigation intervals on yield and its attributes of the Giza178 rice cultivar, as well as, the availability of some micronutrients in the soil. Irrigation treatments were continuous flooding (CF), continuous saturation (CS), irrigation every 6 days (E6D), every 9 days (E9D) and every 12 days (E12D), while the fertilizer treatments were control (without fertilizer), 5t cattle manure ha-1 (CM), 5t compost ha-1 (C), 5t cattle manure +110 kg N ha-1 (CM+110N), 5t compost +110 kg N ha-1 (C+110N) and the recommended N rate of 165 kg N ha-1 (165N). Prolonged irrigation intervals of more than 6 days substantially decreased the yield and its attributes, Fe and Mn concentration in the soil in both seasons. The opposite was true for Zn concentration. Fertilizer sources containing chemical N (165N) alone or 110N with C or CM significantly surpassed each of the two organic sources alone in yield and yield attributes in the two seasons. The application of C+110N fertilizer with irrigation E6D was statistically at par with the recommended interaction (CF irrigation X 165N fertilizer) in yield and its attributes. The total amount of irrigation water applied was decreased by prolonging the irrigation interval. The inverse was true for water saved and water productivity in kg grains m-3. Application of C+110N fertilizer with irrigation E6D recorded the highest water productivity and saved water > 3000 m3 in the two seasons.