The author(s) declare financial support was received for the research, authorship, and/or publication of this article. This research was included in a project for research and development of rice biofortification in Madagascar. The “Rice biofortification in Madagascar” project was supported by HarvestPlus, part of the CGIAR Research Program Agriculture for Nutrition and Health (A4NH), Grant No. 2021H6468.CIR., the CGIAR Research Program on Rice Agri-Food Systems (RICE) and by the Science and Technology Research Partnership for Sustainable Development (SATREPS), Japan Science and Technology Agency (JST)/Japan International Cooperation Agency (JICA)—Grant No. JPMJSA1608. The grain Zn analysis was supported by HarvestPlus funding to JS. MW has been partly funded by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) under Germany’s Excellence Strategy – EXC 2070 – 390732324.