Global warming shifts the composition of the abundant bacterial phyllosphere microbiota as indicated by a cultivation-dependent and -independent study of the grassland phyllosphere of a long-term warming field experiment

Abstract

The leaf-colonizing bacterial microbiota was studied in a long-term warming experiment on a permanent grassland, which had been continuously exposed to increased surface temperature (+2°C) for more than six years. Two abundant plant species, Arrhenatherum elatius and Galium album, were studied. Surface warming reduced stomata opening and changed leaf metabolite profiles. Leaf surface colonization and the concentration of leaf-associated bacterial cells were not affected. However, bacterial 16S ribosomal RNA (rRNA) gene amplicon Illumina sequencing showed significant temperature effects on the plant species-specific phyllosphere microbiota. Warming partially affected the concentrations of cultured bacteria and had a significant effect on the composition of most abundant cultured plant species-specific bacteria. The abundance of Sphingomonas was significantly reduced. Sphingomonas isolates from warmed plots represented different phylotypes, had different physiological traits and were better adapted to higher temperatures. Among Methylobacterium isolates, a novel phylotype with a specific mxaFtype was cultured from plants of warmed plots while the most abundant phylotype cultured from control plots was strongly reduced. This study clearly showed a correlation of long-term surface warming with changes in the plant physiology and the development of a physiologically and genetically adapted phyllosphere microbiota.

Phyllosphere microbiota: Community dynamics and its interaction with plant hosts

“…Environmental factors Ecological factors such as soil type, geographic location, and sampling site, and abiotic factors such as fertilizer application, temperature, moisture, CO 2 level, light, soil property, and nutrient availability, strongly affect the phyllosphere community in different plant species (e.g., Arabidopsis, rice, and maize) (Balint-Kurti et al, 2010;Ren et al, 2015;Agler et al, 2016;Venkatachalam et al, 2016;Wagner et al, 2016;Alsanius et al, 2017;Aydogan et al, 2020). For instance, geographic location and sampling season (i.e., fall versus.…”

“…The leaf bacterial community structure is affected by elevated CO 2 and higher soil temperature in rice (Ren et al, 2015). When exposed to a long‐term elevated temperature, the forb Galium album and the grass Arrhenatherum elatius show altered bacterial phyllosphere microbiotas compared with that of plants kept at control temperature (Aydogan et al, 2020). Studies also established that light (e.g., ultraviolet or full light spectra) can directly or indirectly influence the interaction between the phyllosphere microbiota and plant hosts in maize and sunflower (Balint‐Kurti et al, 2010; Alsanius et al, 2017).…”

Novel bacterial chloromethane degraders of a living tree fern evidenced by 13C-chloromethane incubations

“…Xanthobacteraceae were enriched in a CH Cl-incubated forest soil in a previous study [25], but also detected in the phyllosphere of grassland plants [97], tomatoes [102], and hay [103].…”

“…In contrast, representatives of Propionibacteriaceae and Solirubrobacteraceae capable of CH3Cl degradation have not been described so far. Propionibacteriaceae closely related Friedmaniella members have been found in the phyllosphere of magnolia trees [95], hemlock plants [96], in grasses such as Arrhenatherum elatius [97], in Baccharis dracunculifolia [98] and in hardwood forest trees such as maple, oak and lime [99]. Bacteria of the family Solirubrobacteraceae are strictly aerobic and chemoorganotrophic [100], and have been identified in the phyllosphere of Baccharis dracunculifolia [98], in grasses such as Arrhenatherum elatius [97], and in olive trees [101].…”

“…Arrhenatherum elatius [97], in Baccharis dracunculifolia [98] and in hardwood forest trees such as maple, oak and lime [99]. Bacteria of the family Solirubrobacteraceae are strictly aerobic and chemoorganotrophic [100], and have been identified in the phyllosphere of Baccharis dracunculifolia [98], in grasses such as Arrhenatherum elatius [97], and in olive trees [101].…”