Optimizing nitrogen use efficiency in forest plantations: mechanistic insights from Arabidopsis, crops, and natural forestry ecosystems.

Abstract

Forest plantations, such as poplar and eucalyptus, exhibit high nitrogen requirements that are vital for growth, biomass accumulation, and the production of high-quality timber. However, the investigation of nitrogen use efficiency (NUE) mechanisms in forest plantations lags far behind that in crops. In contrast, natural forest ecosystems, without chemical fertilizer inputs, demonstrate remarkable capacities for biological nitrogen fixation and internal nitrogen cycling. Drawing on nitrogen utilization strategies elucidated in Arabidopsis, crop species, and natural forest ecosystems, this review provides a comprehensive synthesis and proposes strategies to enhance NUE in forest plantations. Key approaches include optimizing root system architecture, increasing intrinsic nitrogen uptake capacity, and harnessing beneficial microorganisms to improve nitrogen utilization. Furthermore, the review highlights the promising opportunities for employing key regulatory genes and synthetic biology approaches to achieve targeted enhancement of NUE in forest plantations.