Agronomic Biofortification to Fight Human Zn Deficiency in Arid Regions

Zinc (Zn) deficiency is now recognized as a major problem of human nutrition worldwide. It is particularly severe where populations depend on cereals as staple food and have insufficient dietary intake of Zn from legumes and animal products. This situation is widespread in arid regions of developing countries such as Iran. 

Biofortification of food plants is a promising strategy to fight mineral malnutrition in these countries. Complementary to breeding for crop varieties with enhanced Zn-efficiency, also the adaptation of farming practices such as cropping system, fertilization and other soil amendments has potential to improve the Zn density of
consumed parts of food plant.
The overall objective of this project is to identify (proof of principle) and investigate management practices potentially suited to biofortify cereal grains in order to alleviate human Zn deficiency in semi-arid to arid regions such as in central Iran where soils are low in available Zn and human populations largely depend on cereals for Zn nutrition. We propose to focus on the possibility to increase the density and nutritional availability of Zn in wheat grains by improving soil fertility in these regions. 

The proposed project has an agricultural and a nutritional arm. In the agronomic arm (Subproject A), we will investigate the potential of various methods to increase soil Zn bioavailability, including the application of organic ligands, composite organic matter amendments, changes in cropping sequence, and mycorrhizal root colonization to
biofortify wheat grains. 
The nutritional arm of the project (Subproject B) aims to evaluate the impact and usefulness of Zn bioforti-fied wheat on Zn status in populations of low socioeconomic status in rural areas. We will evaluate the cur-rent Zn intake, bioavailability and status of rural Iranian populations and evaluate the contribution of biofortified Zn to
maintaining Zn balance and improving Zn retention. This will include dietary surveys, sta-ble isotope studies to monitor Zn absorption, Zn excretion and Zn balance in human subjects consuming varying levels of additional Zn, and a 9-month feeding study to demonstrate the efficacy of wheat foods containing biofortified Zn in
improving Zn status. Biofortified wheat flour will be compared to wheat flour fortified
in the traditional way.
The goal is to obtain information that can be easily translated into recommendation for low-income farmers and public health specialists but at the same time we also aim to improve the under¬standing of limiting mechanisms and processes involved in this type of biofortification in order to enhance the trans¬ferability of the knowledge gained
to other site conditions and management schemes.
The results of the project will be given to agricultural and health authorities, international and national agri-cultural and health research organizations, to extension organizations, farmers, doctors, nutritionists and other stakeholders
involved. The most successful treatments will be tested in a follow-up project of IUT on the field scale on experimental farms.