Uptake, transport and seed deposition of zinc in wheat and maize under varied zinc and nitrogen supply

Official URL: https://risc01.sabanciuniv.edu/record=b2351216 _(Table of contents)

Chronic zinc (Zn) deficiency is a major health issue affecting over two billion people, caused by heavy reliance on staple crops (i.e. wheat, rice and maize) which are inherently low in Zn. This project was devoted to reveal the individual and combined effects of genetic and agronomic Zn biofortification in wheat and maize. The first part focused on understanding the mechanisms involved in differences in uptake and translocation of foliar-applied Zn among wheat and maize species. It was shown that wheat has a greater capacity of leaf uptake and translocation of foliar-applied Zn compared to maize. The second part investigated the effect of nitrogen (N) supply on uptake and accumulation of Zn in maize and wheat. Improving N supply significantly enhanced the shoot accumulation as well as leaf uptake of Zn from foliar Zn sprays in wheat and maize. The third part studied the effectiveness of Zn fertilizers in the form of soil, foliar and soil + foliar for improving growth, grain yield and nutrients uptake by genetically biofortified HarvestPlus wheat genotypes. It was demonstrated that the genetically biofortified genotypes have higher capacity to uptake, utilize and translocate Zn from soil and/or foliar applications as compared to conventional cultivars. These results conclude that the most sustainable way of tackling human Zn deficiency would be to improve grain Zn concentration of cereal crops by unifying genetic and agronomic biofortification strategies.Chronic zinc (Zn) deficiency is a major health issue affecting over two billion people, caused by heavy reliance on staple crops (i.e. wheat, rice and maize) which are inherently low in Zn. This project was devoted to reveal the individual and combined effects of genetic and agronomic Zn biofortification in wheat and maize. The first part focused on understanding the mechanisms involved in differences in uptake and translocation of foliar-applied Zn among wheat and maize species. It was shown that wheat has a greater capacity of leaf uptake and translocation of foliar-applied Zn compared to maize. The second part investigated the effect of nitrogen (N) supply on uptake and accumulation of Zn in maize and wheat. Improving N supply significantly enhanced the shoot accumulation as well as leaf uptake of Zn from foliar Zn sprays in wheat and maize. The third part studied the effectiveness of Zn fertilizers in the form of soil, foliar and soil + foliar for improving growth, grain yield and nutrients uptake by genetically biofortified HarvestPlus wheat genotypes. It was demonstrated that the genetically biofortified genotypes have higher capacity to uptake, utilize and translocate Zn from soil and/or foliar applications as compared to conventional cultivars. These results conclude that the most sustainable way of tackling human Zn deficiency would be to improve grain Zn concentration of cereal crops by unifying genetic and agronomic biofortification strategies