Abstract:
To optimize the application of plant growth-promoting rhizobacteria (PGPR) in field trials, tracking methods are needed to assess their shelf life and to determine the elements affecting their effectiveness and their interactions with plants and native soil microbiota. This work developed a real-time PCR (qtPCR) method which traces and quantifies bacteria when added as microbial consortia, including five PGPR species: Burkholderia ambifaria, Bacillus amyloliquefaciens, Azotobacter chroococcum, Pseudomonas fluorescens, and Rahnella aquatilis. Through a literature search and in silico sequence analyses, a set of primer pairs which selectively tag three bacterial species (B. ambifaria, B. amyloliquefaciens and R. aquatilis) was retrieved. The primers were used to trace these microbial species in a field trial in which the consortium was tested as a biostimulant on two wheat varieties, in combination with biochar and the mycorrhizal fungus Rhizophagus intraradices. The qtPCR assay demonstrated that the targeted bacteria had colonized and grown into the soil, reaching a maximum of growth between 15 and 20 days after inoculum. The results also showed biochar had a positive effect on PGPR growth. In conclusion, qtPCR was once more an effective method to trace the fate of supplied bacterial species in the consortium when used as a cargo system for their delivery.
摘要:
为优化植物根瘤菌(PGPR)在田间试验中的应用,需要跟踪方法来评估其保质期,并确定影响其有效性的因素以及它们与植物和本地土壤微生物群的相互作用。这项工作开发了一种实时PCR(qtPCR)方法,当作为微生物聚生体添加时,可以追踪和定量细菌,包括五个PGPR物种:伯克霍尔德氏菌,解淀粉芽孢杆菌,铜绿固氮菌,荧光假单胞菌,还有Rahnellaaquatilis.通过文献检索和计算机序列分析,一组选择性标记三种细菌物种的引物对(B.ambifaria,解淀粉芽孢杆菌和水草芽孢杆菌)被回收。引物用于在田间试验中追踪这些微生物物种,在该试验中,该财团作为生物刺激剂在两个小麦品种上进行了测试,与生物炭和菌根真菌Rhizophagusintrarades结合使用。qtPCR分析表明,目标细菌已经定植并生长到土壤中,接种后15至20天之间达到最大生长。结果还表明,生物炭对PGPR的生长具有积极作用。总之,qtPCR再一次是一种有效的方法,用于追踪联盟中提供的细菌物种的命运,当用作运输系统时。