Microbiome and Metagenome Analysis Reveals Huanglongbing Affects the Abundance of Citrus Rhizosphere Bacteria Associated with Resistance and Energy Metabolism

The plant rhizosphere microbiome is known to play a vital role in plant health by competing with pathogens or inducing plant resistance. This study aims to investigate rhizosphere microorganisms responsive to a devastating citrus disease caused by ‘Candidatus Liberibacter asiaticus’ (CLas) infection, by using 16S rRNA sequencing and metagenome technologies. The results show that 30 rhizosphere and 14 root bacterial genera were significantly affected by CLas infection, including 9 plant resistance-associated bacterial genera. Among these, Amycolatopsis, Sphingopyxis, Chryseobacterium, Flavobacterium, Ralstonia, Stenotrophomonas, Duganella, and Streptacidiphilus were considerably enriched in CLas-infected roots, while Rhizobium was significantly decreased. Metagenome analysis revealed that the abundance of genes involved in carbohydrate metabolism, such as glycolysis, starch and sucrose metabolism, amino sugar and nucleotide sugar metabolism, was significantly reduced in the CLas-infected citrus rhizosphere microbial community. Likewise, the abundance of genes involved in phosphoinositide signaling and phosphoinositide metabolism, which play important roles in energy metabolism (such as carbohydrate metabolism and lipid metabolism), was also decreased in the CLas-infected samples. Taken together, our results indicate that CLas infection could affect the resistance potential and energy metabolism of the citrus rhizosphere microbial community, which may help us to understand the rhizosphere responses to plant disease and thus facilitate the development and application of antagonistic microorganism products in citrus industry.

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Faculty Opinions recommendation of Dynamic root exudate chemistry and microbial substrate preferences drive patterns in rhizosphere microbial community assembly.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.732864671.793571177 ◽

2020 ◽

Author(s):

Stanislav Kopriva

Keyword(s):

Microbial Community ◽

Community Assembly ◽

Root Exudate ◽

Substrate Preferences ◽

Microbial Community Assembly ◽

Rhizosphere Microbial Community

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Biocontrol Potential of Bacillus altitudinis AMCC1040 against Root-knot Nematode Disease of Ginger and its Impact on Rhizosphere Microbial Community

Biological Control ◽

10.1016/j.biocontrol.2021.104598 ◽

2021 ◽

pp. 104598

Author(s):

Jian-Yu Wang ◽

Cheng Guo ◽

Peng Zhao ◽

Feng-Yuan Yu ◽

Yue Su ◽

...

Keyword(s):

Microbial Community ◽

Root Knot Nematode ◽

Bacillus Altitudinis ◽

Biocontrol Potential ◽

Rhizosphere Microbial Community

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Effects of elevated atmospheric CO2 on rhizosphere microbial community of Pinus densiflora (Korean red pine)

Forest Science and Technology ◽

10.1080/21580103.2020.1866089 ◽

2021 ◽

pp. 1-8

Author(s):

Hyunseok Lee ◽

Wi Young Lee ◽

Jun Won Kang

Keyword(s):

Microbial Community ◽

Pinus Densiflora ◽

Red Pine ◽

Atmospheric Co2 ◽

Elevated Atmospheric Co2 ◽

Korean Red Pine ◽

Rhizosphere Microbial Community

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Allotetraploidization in Brachypodium May Have Led to the Dominance of One Parent’s Metabolome in Germinating Seeds

Cells ◽

10.3390/cells10040828 ◽

2021 ◽

Vol 10 (4) ◽

pp. 828

Author(s):

Aleksandra Skalska ◽

Elzbieta Wolny ◽

Manfred Beckmann ◽

John H. Doonan ◽

Robert Hasterok ◽

...

Keyword(s):

Cell Wall ◽

Tricarboxylic Acid Cycle ◽

Sugar Metabolism ◽

Vital Role ◽

Nutrient Mobilization ◽

Cellular Events ◽

Complex Process ◽

Germinating Seeds ◽

Community Standard ◽

Ecological Range

Seed germination is a complex process during which a mature seed resumes metabolic activity to prepare for seedling growth. In this study, we performed a comparative metabolomic analysis of the embryo and endosperm using the community standard lines of three annual Brachypodium species, i.e., B. distachyon (Bd) and B. stacei (Bs) and their natural allotetraploid B. hybridum (BdBs) that has wider ecological range than the other two species. We explored how far the metabolomic impact of allotetraploidization would be observable as over-lapping changes at 4, 12, and 24 h after imbibition (HAI) with water when germination was initiated. Metabolic changes during germination were more prominent in Brachypodium embryos than in the endosperm. The embryo and endosperm metabolomes of Bs and BdBs were similar, and those of Bd were distinctive. The Bs and BdBs embryos showed increased levels of sugars and the tricarboxylic acid cycle compared to Bd, which could have been indicative of better nutrient mobilization from the endosperm. Bs and BdBs also showed higher oxalate levels that could aid nutrient transfer through altered cellular events. In Brachypodium endosperm, the thick cell wall, in addition to starch, has been suggested to be a source of nutrients to the embryo. Metabolites indicative of sugar metabolism in the endosperm of all three species were not prominent, suggesting that mobilization mostly occurred prior to 4 HAI. Hydroxycinnamic and monolignol changes in Bs and BdBs were consistent with cell wall remodeling that arose following the release of nutrients to the respective embryos. Amino acid changes in both the embryo and endosperm were broadly consistent across the species. Taking our data together, the formation of BdBs may have maintained much of the Bs metabolome in both the embryo and endosperm during the early stages of germination. In the embryo, this conserved Bs metabolome appeared to include an elevated sugar metabolism that played a vital role in germination. If these observations are confirmed in the future with more Brachypodium accessions, it would substantiate the dominance of the Bs metabolome in BdBs allotetraploidization and the use of metabolomics to suggest important adaptive changes.

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