Miebach Moritz, Faivre Léa, Schubert Daniel, Jameson Paula, Remus-Emsermann Mitja
School of Biological Sciences University of Canterbury Christchurch New Zealand.
Biomolecular Interaction Centre University of Canterbury Christchurch New Zealand.
Plant Environ Interact. 2024 Mar 13;5(2):e10137. doi: 10.1002/pei3.10137. eCollection 2024 Apr.
Leaves are colonized by a complex mix of microbes, termed the leaf microbiota. Even though the leaf microbiota is increasingly recognized as an integral part of plant life and health, our understanding of its interactions with the plant host is still limited. Here, mature, axenically grown plants were spray inoculated with six diverse leaf-colonizing bacteria. The transcriptomic changes in leaves were tracked over time and significant changes in ethylene marker () expression were observed only 2-4 days after spray inoculation. Whole-transcriptome sequencing revealed that 4 days after inoculation, leaf transcriptional changes to colonization by nonpathogenic and pathogenic bacteria differed in strength but not in the type of response. Inoculation of plants with different densities of the nonpathogenic bacterium sp. Leaf354 showed that high bacterial titers resulted in disease phenotypes and led to severe transcriptional reprogramming with a strong focus on plant defense. An in silico epigenetic analysis of the data was congruent with the transcriptomic analysis. These findings suggest (1) that plant responses are not rapid after spray inoculation, (2) that plant responses only differ in strength, and (3) that plants respond to high titers of nonpathogenic bacteria with pathogen-like responses.
叶片被多种微生物所定殖，这些微生物统称为叶片微生物群。尽管叶片微生物群越来越被认为是植物生命和健康不可或缺的一部分，但我们对其与植物宿主相互作用的理解仍然有限。在此，用六种不同的叶片定殖细菌对无菌培养的成熟植株进行喷雾接种。随着时间的推移追踪叶片中的转录组变化，仅在喷雾接种后2 - 4天观察到乙烯标记物（）表达的显著变化。全转录组测序显示，接种后4天，非致病性和致病性细菌定殖引起的叶片转录变化在强度上有所不同，但在反应类型上没有差异。用不同密度的非致病性细菌Leaf354接种植物表明，高细菌滴度导致病害表型，并导致严重的转录重编程，且强烈聚焦于植物防御。对数据进行的计算机表观遗传分析与转录组分析结果一致。这些发现表明：（1）喷雾接种后植物反应并不迅速；（2）植物反应仅在强度上有所不同；（3）植物对高滴度非致病性细菌的反应类似于对病原体的反应。
