Li Tongda, Mann Ross, Kaur Jatinder, Spangenberg German, Sawbridge Timothy
Agriculture Victoria, AgriBio, Centre for AgriBioscience, Bundoora, VIC 3083, Australia.
School of Applied Systems Biology, La Trobe University, Bundoora, VIC 3083, Australia.
Plants (Basel). 2021 Aug 30;10(9):1802. doi: 10.3390/plants10091802.
Plant growth-promoting bacteria can improve host plant traits including nutrient uptake and metabolism and tolerance to biotic and abiotic stresses. Understanding the molecular basis of plant-bacteria interactions using dual RNA-seq analyses provides key knowledge of both host and bacteria simultaneously, leading to future enhancements of beneficial interactions. In this study, dual RNA-seq analyses were performed to provide insights into the early-stage interactions between barley seedlings and three novel bacterial strains (two sp. strains and one strain) isolated from the perennial ryegrass seed microbiome. Differentially expressed bacterial and barley genes/transcripts involved in plant-bacteria interactions were identified, with varying species- and strain-specific responses. Overall, transcriptome profiles suggested that all three strains improved stress response, signal transduction, and nutrient uptake and metabolism of barley seedlings. Results also suggested potential improvements in seedling root growth via repressing ethylene biosynthesis in roots. Bacterial secondary metabolite gene clusters producing compounds that are potentially associated with interactions with the barley endophytic microbiome and associated with stress tolerance of plants under nutrient limiting conditions were also identified. The results of this study provided the molecular basis of plant growth-promoting activities of three novel bacterial strains in barley, laid a solid foundation for the future development of these three bacterial strains as biofertilisers, and identified key differences between bacterial strains of the same species in their responses to plants.
植物促生细菌可以改善宿主植物的性状，包括养分吸收与代谢以及对生物和非生物胁迫的耐受性。利用双RNA测序分析来理解植物与细菌相互作用的分子基础，能够同时提供宿主和细菌的关键知识，从而在未来增强有益相互作用。在本研究中，进行了双RNA测序分析，以深入了解大麦幼苗与从多年生黑麦草种子微生物组中分离出的三种新型细菌菌株（两种 sp. 菌株和一种 菌株）之间的早期相互作用。鉴定出了参与植物与细菌相互作用的差异表达细菌和大麦基因/转录本，具有不同的物种和菌株特异性反应。总体而言，转录组图谱表明，所有三种菌株均改善了大麦幼苗的应激反应、信号转导以及养分吸收与代谢。结果还表明，通过抑制根部乙烯生物合成，可能会改善幼苗根系生长。还鉴定出了细菌次生代谢物基因簇，这些基因簇产生的化合物可能与与大麦内生微生物组的相互作用有关，并且与养分限制条件下植物的胁迫耐受性有关。本研究结果提供了三种新型细菌菌株在大麦中促进植物生长活性的分子基础，为这三种细菌菌株未来作为生物肥料的开发奠定了坚实基础，并确定了同一物种的细菌菌株在对植物反应方面的关键差异。
