Project description:Leaves are colonised by a complex mix of microbes, termed the leaf microbiota. Even though the leaf microbiota is increasingly recognised 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 Arabidopsis thaliana plants were spray-inoculated with different densities of the non-pathogenic bacterium Williamsia sp. Leaf354. High bacterial titers caused disease phenotypes and led to severe transcriptional reprogramming with a strong focus on plant defence.
Project description:Leaves are colonised by a complex mix of microbes, termed the leaf microbiota. Even though the leaf microbiota is increasingly recognised 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 Arabidopsis thaliana plants were spray-inoculated with diverse leaf-colonising bacteria. Whole transcriptome sequencing revealed that four days after inoculation, leaf transcriptional changes to colonisation by non-pathogenic and pathogenic bacteria differed in strength but not in the type of response. Inoculation of plants with different densities of the non-pathogenic bacterium Williamsia sp. Leaf354 showed that high bacterial titers caused disease phenotypes and led to severe transcriptional reprogramming with a strong focus on plant defence. This SuperSeries is composed of the SubSeries listed below.
Project description:Leaves are colonised by a complex mix of microbes, termed the leaf microbiota. Even though the leaf microbiota is increasingly recognised 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 Arabidopsis thaliana plants were spray-inoculated with diverse leaf-colonising bacteria. Whole transcriptome sequencing revealed that four days after inoculation, leaf transcriptional changes to colonisation by non-pathogenic and pathogenic bacteria differed in strength but not in the type of response.
2023-05-19 | GSE232251 | GEO
Project description:Appalachian stream leaf litter microbiota under salinization
Project description:The effect of sucrose feeding on gene expression in Arabidopsis thaliana leaves was investigated using affymetrix ATH1 microarrays. For this, petioles of detached leaves were put in a solution containing either sucrose or sorbitol (control). Sugars were taken up into the leaf via the respiration stream for 13 hours. After that, leaves were frozen in liquid nitrogen and RNA was extracted for analysis. Experiment Overall Design: The effect of sucrose feeding on gene expression was investigated using affymetrix ATH1 microarrays. For this, petioles of detached leaves were put in a solution containing either sucrose or sorbitol (control). Sugars were taken up into the leaf via the respiration stream for 13 hours. After that, leaves were frozen in liquid nitrogen and RNA was extracted for analysis.
Project description:We tested whether home field advantage at inter- and intra-specific levels alters microbial carbon transformations, using a multi-factorial design with microcosms of freshwater submerged leaf litter from two species (Alder and Hemlock) exposed to 'home' or 'away' communities of microbes isolated from decomposing leaf litter, as well as controls with no microbial community added. For all 'home', 'away' and control conditions for each species we also had high or low oxygen treatments. Samples were taken at day 0, 154, 257 and 354 and extracted with solid phase columns and methanol to provide extracted metabolites.
Project description:Background: The biological control agent Pseudomonas chlororaphis PA23 is effective at protecting Brassica napus (canola) from the necrotrophic fungus Sclerotinia sclerotiorum via direct antagonism. Despite the growing importance of biocontrol bacteria in plant protection from fungal pathogens, little is known about how the host plant responds to bacterial priming on the leaf surface or about changes in gene activity genome-wide in the presence and absence of S. sclerotiorum. Results: PA23 priming of mature canola plants reduced the number of lesion forming petals by 90%. Global RNA sequencing of the host pathogen interface showed a reduction in the number of genes uniquely upregulated in response to S. sclerotiorum by 16-fold when pretreated with PA23. Upstream defense-related gene patterns suggest MAMP-triggered immunity via surface receptors detecting PA23 flagellin and peptidoglycans. Although systemic acquired resistance was induced in all treatment groups, a response centered around a glycerol-3-phosphate (G3P)-mediated pathway was exclusively observed in plants treated with PA23 alone. Activation of these defense mechanisms by PA23 involved mild reactive oxygen species production as well as pronounced thylakoid membrane structures and plastoglobule formation in leaf chloroplasts. Conclusion: Further to the direct antibiosis that it exhibits towards the pathogen S. sclerotiorum, PA23 primes defense responses in the plant through the induction of unique local and systemic defense regulatory networks. This study has shed light on the potential effects of biocontrol agents applied to the plant phyllosphere. Understanding these interactions will aid in the development of biocontrol systems as a viable alternative to chemical pesticides in the protection of important crop systems. Mature canola leaf tissue treated with combinations of PA23 or S. sclerotiorum ascospores (3 treatment groups) was compared to a water treated control (all treatments done in triplicate).