Role of nitrogen nutrition in biofortification of durum wheat with iron

Official URL: http://192.168.1.20/record=b1476941 (Table of Contents)

Iron (Fe) deficiency is a global nutritional problem in human populations and associated with inadequate dietary intake, especially in developing countries. Increasing Fe concentration of food crops by using agricultural tools represents a realistic and cost-e effective strategy to contribute to dietary intake of Fe and human health. Published data indicates that nitrogen (N) nutritional status of plants has positive impacts on shoot and grain zinc concentrations. The main goal of this PhD thesis was to study the role of N nutrition in root absorption, shoot transportation and grain accumulation of Fe in durum wheat (Triticum durum) plants grown under greenhouse and growth chamber conditions. Application of various soil or foliar Fe fertilizers had either a little effect or remained ineffective on shoot and grain Fe. By contrast, at a given Fe treatment, raising N supply to plants substantially enhanced shoot and grain concentrations of Fe. Inclusion of urea in foliar Fe fertilizers had also a positive impact on grain Fe. In the experiments using the radiolabelled Fe fertilizer (e.g.,59FeEDTA), urea found to facilitate cuticular penetration of the foliarly-sprayed Fe and to improve its transportation into sink organs such as seeds. Root release of phytosiderophores (PS) is an important adaptive mechanism in acquisition of Fe by cereals. Improving plant N status had also a significant impact on release of PS release and root uptake and shoot translocation of PS-complexed. It is concluded that improving N nutritional status of plants represents an important agronomic practice for increasing grain Fe and improving human health.