Effect of sulfur-iron and sulfur-zinc nurition on micro nutrient and nitrogen concentrations in wheat

Deficiency of sulfur (S), iron (Fe) and zinc (Zn) are major problems of plant production affecting yield and quality parameters. Similar in plant production, Fe and Zn deficiencies are also significant global nutritional problems for human beings. For this reason, genetic and agronomic biofortification studies with staple food crops are continuously being intensified.In this thesis study, chlorophyll (SPAD), yield, phytosiderophore release rate and Fe, Zn, N and S concentrations were evaluated in bread (T. Aestivum cv. Adana 99) and durum (T. Durum Desf. cv. Sarıçanak 98) wheat cultivars grown in soil and solution culture with different Fe, Zn and S supply. In vegetative stage low S supply resulted in reductions of chlorophyll, N and particularly S concentrations, whereas N/S ratio was significantly enhanced and Fe and Zn values remained unaffected upon varied S supply. In generative stage, as expected, low S supply resulted in significant reductions of grain and straw yields and harvest index in both wheat cultivars. Low supply of S had no significant impact on grain Zn or N concentrations, however grain Fe values were reduced particularly in the bread wheat cultivar. In nutrient solution experiment, low S supply reduced the root phytosiderophore release rate. Thus, it was suggested that reduction in Fe concentration under low S supply is possibly a result of a restricted synthesis of S dependent phytosiderophores.