Root System Characteristics and Control of Nitrogen Uptake

Summary

In many native ecosystems, acquisition of nitrogen (N) depends on bioavailability of this element at the root surface. However, root system characteristics and how they respond to environmental factors are critical to a better understanding of N acquisition in terrestrial plants. This chapter provides an overview of the recent literature in root system control mechanisms of N uptake. In addition to presenting some of the more recent advances in this area, I have argued that in developing a mechanistic understanding, we must first pay more attention to root characteristics, e.g., longevity, uptake kinetics, and architecture that are often overlooked in studies of N uptake. Experimental approaches and techniques must be developed to monitor these characteristics more routinely along with measurements of the common parameters of root biology, e.g., biomass allocation. Because these root traits often exhibit a considerable amount of tradeoffs relative to each other, it is imperative that they are evaluated collectively rather than singly.