基于代谢网络探究羽毛针禾根鞘土壤微生态通路

羽毛针禾是优良的固沙植物，其根鞘沉积丰富，可形成根—微生物—土界面连续体，能保水调节土壤微生态，促进其他植物定植荒漠。如何利用羽毛针禾防沙、固沙和改良土壤，已成关注点。.本组前期初步探究了羽毛针禾的转录组、根鞘微生物群落结构和根际土壤代谢，发现根鞘微循环良好，选择性募集了丰富的微生物，产生养分活化沙丘土壤；从根鞘分离的细菌，能促进植物在沙土中生长。然而，羽毛针禾与其根鞘微生物之间的物质代谢关联，仍待深究。.本项目预在前期基础上，以根系分泌物为枢纽，建立植物—微生物的物质转化通路；以碳同位素示踪，解析根系分泌物对微生物的驱动性；以分区胁迫根系，探究根系分泌物的应激响应动态及信号通路；以微生物基因组测序，挖掘功能基因和操纵子。最后，联系碳转化、生物量、互作促生等生物途径，建立根鞘代谢的表型网络和分子网络，揭示羽毛针禾—微生物互惠的土壤微生态通路，为应用植物—微生物协同固沙，提供新靶点和新思路。

Stipagrostis pennata is an excellent sand-fixing plant. It has rich rhizosheath deposition and can form a root-microbe-soil interface continuum which can retain moisture and regulate soil microecology. It can promote other plants to colonize in the desert. How to use Stipagrostis pennata to fix sand and improve soil has become a concern...We have preliminary explored the transcriptome, microbial community structure and rhizosphere soil metabolism of Stipagrostis pennata. We found that its rhizosheath has efficient microcirculation and selectively recruits abundant microorganisms to produce nutrient to improve the dune soil vitality. In addition, bacteria isolated from rhizosheath can promote plant growth in sandy soil. However, the pathway of material metabolism between Stipagrostis pennata and its rhizosheath microorganisms awaits further investigations...Based on the earlier work, the present project will use root exudates as the clue to establish a plant-microbe material conversion pathway. We will detect the driving force of root exudates on microorganisms by tracing carbon isotope. We will assess the response and signaling pathway of root exudates by split-root stressing. We will sequence microbial genomes to mine functional genes and operons. We will link the biological pathways, such as carbon conversion, biomass, bio-interaction and -promotion, to build the phenotype network and molecular network of the rhizosheath metabolism. We will reveal soil microecological pathway of Stipagrostis pennata-microbes reciprocity. Finally, we hope to promote the application of plant-microbe-cooperative sand-fixation.