Evaluation of use efficiency and response of different wheat genotypes to iron and zinc

Use of plant genotypes which are efficient in uptake and utilization of nutrients, is an approach that applied for many years but its importance is more realized. In recent years, plant genotypes that are efficient in using of nutrients attracted more attention and use of them is new approach in low external input agriculture in order to increase efficiency of fertilizers. Iron and zinc are essential macronutrient for plants that are also important in human nutrition. The purpose of this study was to identify the efficient genotypes on use efficiency of iron and zinc that can achieve biofortification of iron and zinc in wheat products.

The trial conducted as a factorial experiment in a completely randomized design with three replications in order to investigate use efficiency of iron and zinc in bread wheat genotypes. The experimental factors consisted of 12 wheat genotypes and 4 levels of fertilizer. Wheat genotypes were N87-20, Morvarid, Gonbad, Falat, Tajan, Line90-7, Line91-17, Aftab, Ghabus, Kouhdasht, Karim and Line17. Fertilizer treatments were completely nutrient solution, iron deficiency, zinc deficiency and iron and zinc deficiency. Zinc used as ZnSO4 at zero (deficiency level) and 1µM (sufficient level) and iron used as sequestrine at 1µM (deficiency level) and 100µM (sufficient level).

the results showed that shoot and iron and zinc uptake of shoot significantly reduced due to iron and zinc deficiency, but use efficiency of iron and zinc increased. Deficiency of iron and zinc together reduced more parameters rather than deficiency of each alone, but increased theirs use efficiency. Iron use efficiency of Line90-7 was the best and Line17 and Kouhdasht had the worst. The highest use efficiency of zinc has seen in line17 and lowest one was for Kouhdasht, Tajan, Karim and Ghabus. Classification of genotypes by Gill method based on dry matter weight and use efficiency of iron and zinc in shoot showed Line90-7 and N87-20 were high responsive to iron and zinc respectively and Line90-7 and Line17 were high efficient to iron and zinc respectively. Classification also showed that the Tajan and N87-20 were the best and Line17 and Kouhdasht were poor in uptake and use of iron and zinc and production of dry matter.

The results of this study showed that Tajan and N87-20 genotypes were responsive to iron and zinc fertilizers and had the highest efficiency in using iron and zinc and producing dry matter. Therefore, in order to reduce the cost and environmental effects of chemical fertilizers, we suggest these cultivars for field trials both in fertile and low output lands (iron and zinc deficiency).