Journal Article

Nitrogen acquisition by roots: physiological and developmental mechanisms ensuring plant adaptation to a fluctuating resource

Nacry, Philippe, Gojon, Alain, Bouguyon, Eléonore

2013

Overview

Nitrogen (N) is one of the key mineral nutrients for plants and its availability has a major impact on their growth and development. Most often N resources are limiting and plants have evolved various strategies to modulate their root uptake capacity to compensate for both spatial and temporal changes in N availability in soil. The main N sources for terrestrial plants in soils of temperate regions are in decreasing order of abundance, nitrate, ammonium and amino acids. N uptake systems combine, for these different N forms, high- and low-affinity transporters belonging to multige families. Expression and activity of most uptake systems are regulated locally by the concentration of their substrate, and by a systemic feedback control exerted by whole-plant signals of N status, giving rise to a complex combinatory network. Besides modulation of the capacity of transport systems, plants are also able to modulate their growth and development to maintain N homeostasis. In particular, root system architecture is highly plastic and its changes can greatly impact N acquisition from soil. In this review, we aim at detailing recent advances in the identification of molecular mechanisms responsible for physiological and developmental responses of root N acquisition to changes in N availability. These mechanisms are now unravelled at an increasing rate, especially in the model plant Arabidopsis thaliana L.. Within the past decade, most root membrane transport proteins that determine N acquisition have been identified. More recently, molecular regulators in nitrate or ammonium sensing and signalling have been isolated, revealing common regulatory genes for transport system and root development, as well as a strong connection between N and hormone signalling pathways. Deciphering the complexity of the regulatory networks that control N uptake, metabolism and plant development will help understanding adaptation of plants to sub-optimal N availability and fluctuating environments. It will also provide solutions for addressing the major issues of pollution and economical costs related to N fertilizer use that threaten agricultural and ecological sustainability.

• Publisher: Springer Verlag,CCSD,Springer,Springer Netherlands,Springer Nature B.V
• Subject: Acid soils / Adaptation / Agronomy. Soil science and plant productions / Amino acids / Ammonium / ammonium nitrate / Animal, plant and microbial ecology / Arabidopsis thaliana / Biological and medical sciences / Biological transport, Active / Biomedical and Life Sciences / Ecology / Environmental aspects / environmental sustainability / Fundamental and applied biological sciences. Psychology / Gene expression regulation / General agronomy. Plant production / growth and development / Life Sciences / MARSCHNER REVIEW / metabolism / Nitrates / Nitrogen / Nitrogen content / nitrogen fertilizers / nutrients / Physiology / plant adaptation / Plant cells / plant development / Plant growth / Plant Physiology / Plant roots / Plant Sciences / Plants / plants (botany) / Quaternary ammonium compounds / regulator genes / Root development / Root growth / root systems / roots / Roots (Botany) / Soil Science & Conservation / Soil-plant relationships. Soil fertility / Soil-plant relationships. Soil fertility. Fertilization. Amendments / Soils / temperate soils / temperate zones / temporal variation / transporters / Vegetal Biology
• ISBN: 0003232535000