effect of treated mswc leachate with different salts on growth parameters, chemical composition of barley plant and soil properties

natural organic wastes contain considerable amounts of nutritional elements. the availability and uptake of nutrient elements in soil) especially in alkali and calcareous soils) increase due to high content of organic matter, and reduce the micro-elements deficiencies. organic wastes have pathogenic contaminations that come from waste type and transmitted by microorganisms such as bacteria, fungi, etc. this research was conducted to study the effect of mswc leachate treated with three salts, 1) cupper sulphate, 2) iron chloride and 3) sodium benzoate each with two levels of 40 and 80 mg.l-1 on growth parameters of barley and soil properties in a completely randomized design (factorial) with three replications under laboratory and pot conditions in college of agriculture, ferdowsi university of mashhad during 2009-2010 cropping season. results showed that plant total dry weight in three different salts were not significant. maximum n and k concentrations in plant were observed in cupper sulphate treated mswc leachate and plant p concentration in cupper sulphate and iron chloride treated mswc leachate treatments. the effect of sodium benzoate, due to its positive impact and benzoic acid produced, as plant metabolite was superior to iron chloride. increasing amount of salt from 40 to 80 mg.l-1, increased soil ece, reduced plant height and total dry weight, n and p concentrations. plant height, total dry weight, plant p and k concentrations were maximum and n concentration ranked second in 40 mg.l-1 cupper sulphate salt. maximum reduction in plant height and total dry weight was noted in iron chloride with increasing salt amount, and minimum n concentration was noted in this treatment. soil ece in cupper sulphate ranked third and soil total n in sodium benzoate 80 and cupper sulphate 40 mg.l-1 treatments ranked first and soil available k in cupper sulphate 40 mg.l-1 ranked second. our results showed that cupper sulphate 40 mg.l-1 treatment is suitable salt and amount for treating mswc leachate to obtain maximizing plant growth and total dry weight.