Department of Biological Sciences and Canadian Centre for World Hunger Research (CCWHR), University of Toronto, Toronto M1C 1A4, ON, Canada; Département de Phytologie, Faculté des Sciences de l'Agriculture et de l'Alimentation (FSAA), Université Laval, Québec G1V 0A6, QC, Canada.
Department of Biological Sciences and Canadian Centre for World Hunger Research (CCWHR), University of Toronto, Toronto M1C 1A4, ON, Canada.
Trends Plant Sci. 2017 Aug;22(8):661-673. doi: 10.1016/j.tplants.2017.05.004. Epub 2017 Jun 7.
Although the global nitrogen (N) cycle is largely driven by soil microbes, plant root exudates can profoundly modify soil microbial communities and influence their N transformations. A detailed understanding is now beginning to emerge regarding the control that root exudates exert over two major soil N processes - nitrification and N fixation. We discuss recent breakthroughs in this area, including the identification of root exudates as nitrification inhibitors and as signaling compounds facilitating N-acquisition symbioses. We indicate gaps in current knowledge, including questions of how root exudates affect newly discovered microbial players and N-cycle components. A better understanding of these processes is urgent given the widespread inefficiencies in agricultural N use and their links to N pollution and climate change.
尽管全球氮 (N) 循环在很大程度上是由土壤微生物驱动的，但植物根系分泌物可以深刻地改变土壤微生物群落，并影响它们的 N 转化。现在，人们开始详细了解根系分泌物对两种主要土壤 N 过程——硝化和固氮的控制作用。我们讨论了这一领域的最新突破，包括将根系分泌物鉴定为硝化抑制剂和作为促进 N 吸收共生的信号化合物。我们指出了当前知识中的空白，包括根系分泌物如何影响新发现的微生物参与者和 N 循环成分的问题。鉴于农业 N 使用的广泛效率低下及其与 N 污染和气候变化的联系，迫切需要更好地了解这些过程。
