Despite its extensive use as a nitrogen fertilizer, the role of urea as a directly accessible nitrogen source for crop plants is still poorly understood. So far, the physiological and molecular aspects of urea acquisition have been investigated only in few plant species highlighting the importance of a high-affinity transport system.
Zanin et al BMC Plant Biology 2014, 14:222 http://www.biomedcentral.com/1471-2229/14/222 RESEARCH ARTICLE Open Access Isolation and functional characterization of a high affinity urea transporter from roots of Zea mays Laura Zanin1*, Nicola Tomasi1, Corina Wirdnam2, Stefan Meier2, Nataliya Y Komarova2, Tanja Mimmo3, Stefano Cesco3, Doris Rentsch2 and Roberto Pinton1 Abstract Background: Despite its extensive use as a nitrogen fertilizer, the role of urea as a directly accessible nitrogen source for crop plants is still poorly understood So far, the physiological and molecular aspects of urea acquisition have been investigated only in few plant species highlighting the importance of a high-affinity transport system With respect to maize, a worldwide-cultivated crop requiring high amounts of nitrogen fertilizer, the mechanisms involved in the transport of urea have not yet been identified The aim of the present work was to characterize the high-affinity urea transport system in maize roots and to identify the high affinity urea transporter Results: Kinetic characterization of urea uptake (