?url_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.aufirst=T&rft.au=Nakamura%2C+T&rft.aulast=Nakamura&rft.atitle=Varietal+differences+in+root+growth+as+related+to+nitrogen+uptake+by+sorghum+plants+in+low-nitrogen+environment&rft.title=Plant+and+Soil&rft.date=2002&rft.volume=245&rft.pages=17-24&rft.issue=1&rft.genre=article