Efficiencies of mikronized-bentonite-sulfur and its derivatives with iron (Fe) and zinc (Zn) on organically grown greenhouse tomato

In organic tomato growing in greenhouse five different sulfur product, which applied to soil, have been investigated. The sulfur products were: 1) Micronized-bentonite-sulfur, 2) Traditional granular sulfur, 3) Micronized-bentonite-sulfur+iron (Fe), 4) Micronized-bentonite sulfur+zinc (Zn), 5) Micronized-bentonite-sulfur+iron (Fe)+zinc (Zn) and without any application control. The effects of the treatments on plant growth, yield and fruit quality properties of tomato crop, also soil pH, soil Fe and Zn concentrations and plant nutrient concentrations of the tomato plants were investigated. The following parameters; plant height, leaf number, cluster number, stem diameter, shoot fresh and dry weights, leaf area, fruit physical properties like weight, diameter, height, volume, fruit chemical properties like total soluble solids in (Brix ), titratable total acidity, vitamin C, fruit pH and macro and micro mineral concentrations in leaves, and also soil pH, EC, Fe, Zn, Mn, Cu concentrations were examined. In plant growth parameters, total yield, fruit quality characteristics, leaf nutrient concentrations, the significant differences in terms of applications have not been determined. Only in April, leaf Fe concentrations of micronized- bentonite-sulfur application were higher. While initial pH 7.80 in greenhouse soil, in all applications, such as soil pH values over a period of 5 months (February to June) 0.16 and 0.36 unit falls occurred. pH desreases were recorded even in the control plots which sulfur was not applied. In this experiment intensitive usage of solid and liquid organic fertilizers for organic nurition of tomato plants may led to pH drop in soil. There for, pH lowering efficiencies of bentonite-micronized sulfur and granular sulfur applications were masked. While soil concentrations of Zn was found high in Zn included bentonite-micronized-sulfur applications, a in-significant differences were recorded in Fe included applications. Key Words: Solanum lycopersicum, organic greenhouse, micronized-sulfur with bentonite,soil pH