Santoro Maricel V, Bogino Pablo C, Nocelli Natalia, Cappellari Lorena Del Rosario, Giordano Walter F, Banchio Erika
Department of Biología Molecular, Facultad de Ciencias Exactas, Químicas y Naturales, Universidad Nacional de Río Cuarto Río Cuarto, Argentina.
Front Microbiol. 2016 Jul 19;7:1085. doi: 10.3389/fmicb.2016.01085. eCollection 2016.
Many species or strains of the genus Pseudomonas have been characterized as plant growth promoting rhizobacteria (PGPR). We used a combination of phenotypic and genotypic techniques to analyze the community of fluorescent Pseudomonas strains in the rhizosphere of commercially grown Mentha piperita (peppermint). Biochemical techniques, Amplified rDNA Restriction Analysis (ARDRA), and 16S rRNA gene sequence analysis revealed that the majority of the isolated native fluorescent strains were P. putida. Use of two Repetitive Sequence-based PCR (rep-PCR) techniques, BOX-PCR and ERIC-PCR, allowed us to evaluate diversity among the native strains and to more effectively distinguish among them. PGPR activity was tested for the native strains and reference strain P. fluorescens WCS417r. Micropropagated M. piperita plantlets were exposed to microbial volatile organic compounds (mVOCs) emitted by the bacterial strains, and plant biomass parameters and production of essential oils (EOs) were measured. mVOCs from 11 of the native strains caused an increase in shoot fresh weight. mVOCs from three native strains (SJ04, SJ25, SJ48) induced changes in M. pierita EO composition. The mVOCs caused a reduction of metabolites in the monoterpene pathway, for example menthofuran, and an increase in menthol production. Menthol production is the primary indicator of EO quality. The mVOCs produced by native strains SJ04, SJ25, SJ48, and strain WCS417r were analyzed. The obtained mVOC chromatographic profiles were unique for each of the three native strains analyzed, containing varying hydrocarbon, aromatic, and alogenic compounds. The differential effects of the strains were most likely due to the specific mixtures of mVOCs emitted by each strain, suggesting a synergistic effect occurs among the compounds present.
许多假单胞菌属的物种或菌株已被鉴定为植物促生根际细菌（PGPR）。我们使用表型和基因型技术相结合的方法，分析了商业种植的薄荷（Mentha piperita）根际荧光假单胞菌菌株群落。生化技术、扩增rDNA限制性分析（ARDRA）和16S rRNA基因序列分析表明，大多数分离出的本地荧光菌株是恶臭假单胞菌。使用两种基于重复序列的PCR（rep-PCR）技术，即BOX-PCR和ERIC-PCR，使我们能够评估本地菌株之间的多样性，并更有效地对它们进行区分。对本地菌株和参考菌株荧光假单胞菌WCS417r进行了PGPR活性测试。将微繁殖的薄荷植株暴露于细菌菌株释放的微生物挥发性有机化合物（mVOCs）中，并测量植物生物量参数和精油（EOs）产量。11种本地菌株的mVOCs导致地上部鲜重增加。3种本地菌株（SJ04、SJ25、SJ48）的mVOCs诱导了薄荷EO成分的变化。这些mVOCs导致单萜途径中的代谢产物减少，例如薄荷呋喃，同时薄荷醇产量增加。薄荷醇产量是EO质量的主要指标。对本地菌株SJ04、SJ25、SJ48和菌株WCS417r产生的mVOCs进行了分析。所获得的mVOC色谱图对于分析的三种本地菌株中的每一种都是独特的，包含不同的烃类、芳香族和外来化合物。菌株的不同影响很可能是由于每种菌株释放的mVOCs的特定混合物，这表明所存在的化合物之间发生了协同作用。
