AUTHOR=Von Wirén Nicolaus TITLE=Grand Challenges in Plant Nutrition JOURNAL=Frontiers in Plant Science VOLUME=2 YEAR=2011 URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2011.00004 DOI=10.3389/fpls.2011.00004 ISSN=1664-462X