Effect of nitrogen on uptake, remobilization and partitioning of zinc and iron throughout the development of durum wheat

Abstract

Deficiencies of zinc (Zn) and iron (Fe) are global nutritional problems and caused most often by their limited dietary intake. Increasing Zn and Fe concentrations of staple food crops such as wheat is therefore an important global challenge. This study investigated the effects of varied nitrogen (N) and Zn supply on the total uptake, remobilization and partitioning of Zn, Fe and N in durum wheat throughout its ontogenesis. Plants were grown under greenhouse conditions with high or low supply of N and Zn, and harvested at 8 different developmental stages for analysis of Zn, Fe and N in leaves, stems, husks and grains. The results obtained showed that the Zn and Fe uptake per plant was enhanced up to 4fold by high N supply while the increases in plant growth by high N supply were much less. When both the Zn and N supplies were high, approximately 50% of grain Zn and 80% of grain Fe were provided by post-anthesis shoot uptake, indicating that the contribution of remobilization to grain accumulation was higher for Zn than for Fe. At the high N and Zn application, about 60% of Zn, but only 40% of Fe initially stored in vegetative parts were retranslocated to grains, and nearly 80% of total shoot Zn and 60% of total shoot Fe were harvested with grains. All these values were significantly lower at the low N treatment. Results indicate that N nutrition is a critical factor in both the acquisition and grain allocation of Zn and Fe in wheat.

Hydrolysed wool: a novel soil amendment for zinc and iron biofortification of wheat

“…Nutritional iron deficiency is estimated to still affect 1.5Á2 billion people worldwide (Lynch 2011). Iron deficiency impairs physical growth, mental development and learning capacity in children, reduces productivity in adults and represents the most common cause of anaemia (Kutman et al 2011). Wheat grains are the most important food staple globally, but wheat is inherently too low in easily absorbable Zn and Fe to supply the recommended dietary intake of these micronutrients .…”

“…The combined application of N and Zn fertilizer has a synergistic effect on grain Zn concentration (Kutman et al 2011). Nitrogen application and N availability also positively affects wheat grain protein concentration (Dupont et al 2006).…”

Crop yield and micronutrient contents (Cu, Fe, Mn and Zn) in spring wheat grain depending on the fertilization method

“…According to Kutman et al (2011), an increase in the dose of nitrogen (from 40 to 50 mg N . kg -1 dry soil) increased the Fe content in wheat grains from 38% to 60%.…”

Agro-Biofortification of Iron and Zinc in Edible Portion of Crops for the Global South

“…9 It may be used to gain both Zn and protein density wheat in future. 19 Most of the results proved that Fe or Zn can retranslocate from source leaf to grain to some extent.…”