Use of Gypsum and Sulphur for Improving Rock P Efficiency and Their Effect on Wheat Productivity and Soil Properties

ABSTRACT: Two field experiments were conducted in the Experimental Farm of Sids, Agricultural Research Station, ARC, Beni-Suef Governorate, Egypt on wheat (Triticum aestivum L.) to evaluate the effect of gypsum (0.0, 2.5 and 5.0 ton/fed) and sulphur (0.0, 200 and 300 kg/fed) on the efficiency of natural rock P at rate of (0.0 and 400 kg/fed), under the slightly alkaline soil and their effect on wheat productivity and some soil properties and fertility after wheat harvest. The results show that added 400kg rock P increased wheat growth (plant height and dry weight/plant), yield components (number of spikes/m2, number of grains/spike and 1000-grain weight), yields (grain and straw), nutrients uptake (N, P and K uptake in grains and/or straw) and soil available P after harvest. Increasing gypsum levels improved all studied growth parameters, yields and yield components, nutrients uptake as well as improved soil reaction , salinity and soil available P after harvest . Sulphur application increased plant height, dry weight/plant, number of spikes/m2, nutrient uptake, soil reaction and soil available P. Mixed gypsum or sulphur with natural rock P enhanced its effect on increasing wheat productivity and some soil properties and phosphorus availability after wheat harvest. The treatment of 400 kg rock P + 5.0 t/fed gypsum seems to be the favorable treatment for maximizing the wheat productivity and enhancing soil properties.