Is it the need of the day?  

If researchers would focus more on zn-fe rich sources and getting them understood, how to integrated them into agriculture, food systems and diets we would have no need to make questions like this.  Too much cereal is the problem that is harming our soil/environment, economy, people/society.  Focusing more on cereal is not the solution.  The seeds don't need to change, the people and our systems do.  

This is surely the need of day. A large population of the world is facing micronutrients malnutrition specially of Zn, Fe and Se. Unfortunately, our cereals (to be used as staple foods) are deficient in Zn and Fe contents and without proper biofortifying cereals with these nutrients. Simultaneous Biofortification approaches seems more attractive because in regions of the world (like south Asia) where both Zn and Fe are deficient in about 1/3rd population, biofortification of single nutrient may not serve the purpose. When you are planning any study of such type, the most important factor is interactions of these nutrients in soil plant system.

Anyways Dear Nordin, if you don't like the question, you do not need to answer.

Best wishes,

This is truly the call of the time that we have ahead  to have a crop , either annual or perennial in nature . Developing nutrient dense crops is the most challenging job ahead of all of us.  And , unfortunately in a natural system , especially under low pH soils,  both nutrients  interact candidly , much  less to the benefit the crop , resultantly you cant have a crop well supplied with Fe and Zn . Interestingly , the concentration of these two nutrients in all edible parts is so low that sometimes its difficult to analyse even by ICP. Our  current studies on germplasm diversity  is unduly tilted towards finding ways and means to address pests and diseases in addition to other yield and quality traits , leaving distinctively the most important aspect , how such plant biodiversity can really look at addressing such chronically rampant multiple micronutrient deficiencies in soils of varied nature .

I am also looking for literature on ZnXFe in crop plants - we have one in J. Cereal Sci.

Fe and Zn are highly correlated in most crops, and breeding for one of them simultaneously increases the other - we have observed this for common bean as well as pearl millet (see e.g. Pfeiffer & McClafferty 2007). However, in rice and wheat for example, the natural variability for Fe is too low to reach levels that could have a significant positive health impact. HarvestPlus (www.harvestplus.org) is breeding for high Zn rice, high Zn wheat and high Fe pearl millet (focus countries are India, Bangladesh and Pakistan). Other target crops for Asia are lentil, sorghum, and cowpea.

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