Dataset Information

Transcriptional characterization of maize roots in response to urea and nitrate

ABSTRACT: Although urea is the most used nitrogen fertilizer worldwide, little is known on the capacity of crop plants to use urea per se as a nitrogen source for development and growth. To date, the molecular and physiological bases of its transport have been investigated only in a limited number of species. In particular, up to date only one study reported the transcriptomic modulation induced by urea treatment in the model plant Arabidopsis (Mérigout et al., 2008 doi: 10.1104/pp.108.119339). In maize, one of crops using huge amount of urea, only a physiological characterization of uptake and assimilation of the N-source has been conducted. General aim of the present work was the comprehension of the molecular basis of urea uptake and assimilation in maize plants, using a transcriptomic approach. In addition, the work focused on the possible interactions between the two main N-sources, conceivably occurring concomitantly in the soil, urea and nitrate. 5 dd-old maize plants were treated for 8 hours with nutrient solution containing nitrogen in form of urea; nitrate; urea and nitrate; or not exposed to any form of nitrogen. Three different biological replicates were used for each sample repeating the experiment three times. All samples were obtained pooling roots of six plants.

ORGANISM(S): Zea mays

SUBMITTER: Anita Zamboni Zeno Varanini Roberto Pinton Laura Zanin Stefano Cesco Nicola Tomasi

PROVIDER: E-GEOD-53102 | ArrayExpress | 2015-03-07

SECONDARY ACCESSION(S): GSE53102PRJNA230837

REPOSITORIES: GEO, ArrayExpress

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Publications

Transcriptomic analysis highlights reciprocal interactions of urea and nitrate for nitrogen acquisition by maize roots.

Zanin Laura L Zamboni Anita A Monte Rossella R Tomasi Nicola N Varanini Zeno Z Cesco Stefano S Pinton Roberto R

Plant & cell physiology 20141217 3

Even though urea and nitrate are the two major nitrogen (N) forms applied as fertilizers in agriculture and occur concomitantly in soils, the reciprocal influence of these two N sources on the mechanisms of their acquisition are poorly understood. Therefore, molecular and physiological aspects of urea and nitrate uptake were investigated in maize (Zea mays), a crop plant consuming high amounts of N. In roots, urea uptake was stimulated by the presence of urea in the external solution, indicating ...[more]

PMID: 25524070

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