Major results of the 3rd phase of the HarvestZinc project are summarized below: 

The results obtained clearly revealed the great potential benefit of combining genetic and agronomic biofortification efforts. Some of recently developed HarvestPlus-biofortified wheat cultivars with high zinc responded very positively to foliar application of micronutrients and showed further increases in  grain concentrations of Zn. These cultivars had also similar (even more yield) compared to the local wheat cultivars. Although very high improvement in grain Zn seems to have been achieved by genetic biofortification (breeding) through HarvestPlus activities, it is seen that it is difficult, if not impossible, to improve grain micronutrient concentrations to desired targeted levels (such as extra 20-25 ppm Zn in grain) without the contribution of agronomic biofortification. Synergism between breeding and fertilizer strategies needs to be used more extensively in future.

Phase 3 has continued to study the effects of various micronutrient-containing foliar fertilizers on grain concentrations of selected micronutrients (Zn, Fe, Se and iodine) in rice and wheat. A total of 16 and 27 experiments were conducted on rice and wheat in 7 countries, respectively. There were substantial increases in grain iodine after foliar spray of iodine containing solutions, indicating that fertilizer strategy could be also an effective solution to the well-documented iodine deficiency problem in human populations globally. A further important finding is the great effectiveness of foliar cocktail solutions (Zn, Fe, Se and iodine) on improving more than one micronutrient concentration at the same time. 

In the studies comparing maize with wheat in terms of foliar uptake and soot translocation of Zn it was very clear that wheat absorbs and transports Zn much better than maize. This finding is in good agreement with the results showing less response of maize than wheat in terms of increasing grain Zn after foliar spray.