Zinc is a vital mineral for human health. It is involved in numerous aspects of cellular metabolism, plays a role in immune function, supports normal growth, et cetera. Zinc deficiency is therefore detrimental for human well-being and can lead to growth retardation, loss of appetite, and an impaired immune function. Mild to moderate zinc deficiency is common worldwide and is therefore a public health issue (WHO).
An adequate zinc status can be achieved for instance via a balanced diet, or when this is difficult to obtain, as is often the case in developing regions, it can be achieved via supplementation, or ferti-fortification of crops. The latter means fertilisation of crops with micronutrients, by which the level of the micronutrient in the crop is increased.
Ferti-fortification can largely help alleviating micronutrient deficiencies in humans, such as the aforementioned zinc deficiency. Especially by fortifying a staple crop such as wheat, a large population group of the world can be helped. Originally, wheat is fertilized with large quantities of micronutrients, leading to nutrient wastage and environmental pollution. Given this, more and more research is performed to study how this wastage and pollution can be combated, while at the same time the crop is indeed fortified with the micronutrient of interest and the yield is furthermore not affected.
In a recent study by Dapkekar et al., durum wheat was ferti-fortified with the nanofertilizer ‘zinc complexed chitosan nanoparticles’ (Zn-CNP) in field-scale experiments. The grain zinc enrichment of the durum wheat with Zn-CNP was comparable with the conventional method, despite using 10 folds less zinc. The total grain yield was not affected, neither was the protein content and spikelets per spike, among others. Their trial shows that it is possible to enrich wheat with zinc while using much less zinc, while booking the same results in the final produce. This means that less micronutrients are wasted, and the environmental pollution may decrease.
It is the need of the day to grow wheat with inherent high yielding capacity and high protein, considering the increased global food demand and the presence of ‘hidden hunger’ including zinc deficiency. Dapkekar et al. describe their work as a new paradigm in micronutrient fortification: “use nanofertilizers at the right place, right time and in the right doses”.