摘要
根际是养分进入作物系统的门户,也是土壤-根系-微生物相互作用的微域。根际界面过程决定了氮磷养分的供应强度和有效性,最终影响了氮磷养分的利用效率和作物生产力。近年来,国内外在揭示农田土壤-根系-微生物系统中不同界面的养分转化、吸收和运输机制方面取得了一些新进展。在不同时空尺度上分析了影响土壤氮磷转化微生物组成的影响因子;研究了丛枝菌根系统形成的信号机制及其对氮磷吸收的基因调控机制;从信号网络、根系质子分泌和根构型的角度系统揭示了作物根系应对根际环境氮磷养分供应的形态和生理响应机制。未来针对根际氮磷高效利用问题,需要深入研究土壤-根系-微生物不同界面的协同机制和调控原理,在根际微域和土壤团聚体尺度开展微生物食物网及其关键功能微生物分布格局和演替规律的研究;揭示根构型对根系–微生物协同结构和功能的影响,研究养分缺乏条件下根内质子分泌和关键转运蛋白对根系生长和养分吸收的调控机制;针对粮食作物,研究根系-微生物对话中已知信号物质(如独脚金内酯和N-酰基高丝氨酸内酯)和新的信号物质(小RNA)的网络作用机制及其对多养分协同代谢的影响;最后,针对不同气候、土壤、作物类型区,提出提高氮磷利用效率的根际生物调控途径和措施。
Rhizosphere is not only the gateway for soil nutrients entering plants, but also the microzone for the interaction among plant, soil and microorganisms. Rhizosphere determines the supply strength and effectiveness of nitrogen and phosphorus, which in turn affects the nutrient use efficiency and crop productivity. The recent progress of research on the synergy transformation and transportation of nutrients in soil-root-microbe systems was reviewed. The factors driving the change of microbial community composition relative to the turnover of nitrogen and phosphorus were investigated at different spatial-temporal scales. The signal network regulating the formation of arbuscular mycorrhizal systems and the genetic control mechanisms to affect the translocation of nitrogen and phosphorus were studied. The ecophysiological response mechanisms of the roots adapting soil nutrient conditions were revealed by signal networks, root exudates regulating root growth, and the relationship between crop root architecture and nitrogen and phosphorus use efficiency. In the future, we need to deepen our knowledge of soil-root-microbial synergy mechanisms at the differently interfaces by studying： 1） the distribution pattern and succession law for microbial food web and its key function groups in rhizospheres and soil aggregates; 2） the impacts of root architecture on the functions of root-microbe coordination system, and the regulatory mechanisms for root proton secretion and nutrient transport proteins on root growth and nutrient uptake under the nutrient deficient conditions; and 3） the signaling networks and their impacts on nutrient use for known signals （such as strigalactone and N-acyl-homoserine lactones （AHLs） and new signal substances （such as microRNA）. Finally, the biological regulatory pathways and countermeasures should be proposed to increase the utilization efficiency of nitrogen and phosphorus under different climate, soil and crop regimes.
出处
《土壤》
CAS
CSCD
北大核心
2015年第2期210-219,共10页
Soils
基金
中国科学院战略性先导科技专项(XDB15030200)资助
关键词
土壤-根系-微生物系统
协同机制
氮磷养分
转化和代谢
信号网络
Soil-root-microbe system
Synergy mechanism
Nitrogen and phosphorus
Metabolism and translocation
Signal network
