مشخصات پژوهش

Zn deficiency is a worldwide nutritional constraint in crop production particularly in cereals growing calcareous soils. In order to study the effect of different zinc-sulfate application methods on grain yield, agronomy traits and grain micronutrients of wheat, a pot experiment was carried out in a calcareous soil in factorial experiment at randomized complete block design (RCBD) with 30 treatments (6 Zn application methods, and 5 wheat genotypes) in four replications. Treatments were the first factor included six levels of applied Zn were (1) control (non Zn application), (2) soil application (5 mg Zn kg-1 soil), (3) seed application (3% (w/v) Zn for 1 kg seed), (4) foliar application at stem elongation and early grain filling stages (zinc sulfate was sprayed at a rate of 0.44 g Zn l-1, (5) seed spray + foliar (combination of methods 3 and 4) and (6) soil + foliar (combination of methods 2 and 4), and also the second factor was five wheat genotypes including two spring bread wheat (‘Pishtaz’ and ‘Sivand’) and three spring durum wheat (‘Diyarbakır-81’, ‘Bisu-1’ and line ‘45558’). Both soil and foliar Zinc application methods could improve yield and grain Zn concentration; however, generally bread wheat had the better agronomic traits, grain yield as well as Zn, Fe, Cu and Mn concentrations in grain compared with durum wheat. The foliar Zn application was more effective in increasing Zn, Fe, Mn and ascorbic acid concentrations in grain. Different Zn treatments methods significantly increased Zn concentration and decreased phytate content of the wheat grain, as well as decreased grain phytate/Zn molar ratios. Thus, it seems that soil and foliar Zn application would improve the quantity and quality of the wheat yield in Zndeficient soils. Therefore, fertilizer strategy (e.g., agronomic biofortification) appears as short-term solution to alleviate malnutrition problem