Dataset Information

Impact of salt and exogenous AM inoculation on indigenous microbial community structure in the rhizosphere of dioecious plant, Populus cathayana.

ABSTRACT: The sex-specific physical and biochemical responses in dioecious plants to abiotic stresses could result in gender imbalance, and how to ease the current situation by microorganisms is still unclear. Using native soil where poplars were grown, growth parameters, soil physicochemical properties in the rhizosphere soil of different sexes of Populus cathayana exposed to salt stress and exogenous arbuscular mycorrhizal (AM) inoculation were tested. Besides, the sex-specific microbial community structures in the rhizosphere soil of different sexes of Populus cathayana were compared under salt stress. To identify the sex-specific microbial community characteristics related to salinity and AM symbiosis, a combined qPCR and DGGE method was used to monitor microbial community diversity. Seedlings suffered severe pressure by salt stress, reflected in limited growth, biomass, and nutrient element accumulation, especially on females. Exogenous AM inoculation treatment alleviated these negative effects, especially under salt treatment of 75 mM. Compared with salt effect, exogenous AM inoculation treatment showed a greater effect on soil physical-chemical properties of both sexes. Based on DGGE results, salt stress negatively affected fungal richness but positively affected fungal Simpson diversity index, while exogenous AM inoculation treatment showed the opposite effect. Structural equation modeling (SEM) was performed to show the causal relationships between salt and exogenous AM inoculation treatments with biomass accumulation and microbial community: salt and exogenous AM inoculation treatment showed complicated effects on elementary concentrations, soil properties, which resulted in different relationship with biomass accumulation and microbial community. Salt stress had a negative effect on soil properties and microbial community structure in the rhizosphere soil of P. cathayana, whereas exogenous AM inoculation showed positive impacts on most of the soil physical-chemical properties and microbial community status.

SUBMITTER: Wu N

PROVIDER: S-EPMC8443550 | biostudies-literature |

REPOSITORIES: biostudies-literature

ACCESS DATA

Similar Datasets

Project description:Four exogenous genes, Cry3A, Cry1Ac, mtlD, and BADH, were inserted into the p1870 vector to obtain multigenic transgenic Populus nigra L. with improved insect resistance and salt tolerance. During vector construction, different promoters were used for each gene, the AtADH 5'-UTR enhancer was added between the Cry1Ac promoter and the target gene, and the matrix attachment region (MAR, GenBank: U67919.1) structure was added at both ends of the vector. It was then successfully transferred into the genome of European black poplar by Agrobacterium-mediated leaf disk transformation, and a total of 28 transgenic lines were obtained by kanamycin screening. Five events with the highest insect resistance were selected based on preliminary tests: nos. 1, 7, 9, 12, and 17. PCR, real-time PCR, and enzyme-linked immunosorbent assays (ELISA) were used to detect the expression of exogenous genes and to analyze the Bt protein toxin levels in transgenic lines from June to October. PCR results showed that all four genes were successfully introduced into the five selected lines. Fluorescence quantitative PCR showed no significant differences in the transcript abundance of the four exogenous genes between different lines. A Bt protein toxin assay showed that the Cry3A protein toxin content was significantly higher than the Cry1Ac protein toxin content by approximately three orders of magnitude. Levels of the two toxins were negatively correlated. Over the course of the growing season, Cry1Ac content raised and varied between 0.46 and 18.41 ng·g-1. Cry3A content decreased over the same time period and varied between 2642.75 and 15775.22 ng·g-1. Indoor insect feeding assay showed that the transgenic lines had high insect resistance, with mortality rates of 1-2-year-old Hyphantria cunea larvae reaching more than 80%, and those of Plagiodera versicolora larvae and nymphs reaching 100%. No. 17 and no. 12 lines had better insect resistance to Lepidoptera and Coleoptera pests. There was no clear improvement in salt tolerance of the transgenic lines, but comprehensive evaluation of 11 salt tolerance indicators showed that lines no. 17 and no. 7 had certain degrees of salt tolerance.

Project description:Hordeum vulgare is an important source of feed and forage for livestock, and of food and drink for humans, but its utilization rate is lower than that of other cereal crops, thus it is crucial to improve barley agronomic traits and production. Epichloë bromicola is an endophyte that was isolated from wild barley (Hordeum brevisubulatum). Previous studies have found that Epichloë can indirectly influence the growth of host plants by affecting soil chemical characteristics, the microbial community, and by producing a range of secondary metabolites. However, underlying effects of Epichloë on the abundance and diversity of soil and root microbes have not been well-studied. In addition, there is a question regarding the relationship between endophyte-produced alkaloids and effects on the root and rhizosphere microbial communities. The objective of this study was to investigate changes in agronomic traits, nutritional properties, peramine, soil chemical and microbial community in the fourth generation of new barley symbionts EI (E. bromicola-infection) and EF (E. bromicola-free) in LQ+4 and LZ+4. We understand the plant height and biomass of EI in LZ+4 were significantly higher than those of EF. The HPLC analysis showed that the peramine content of EI in LQ+4 and LZ+4 was 0.085 and 0.1 mg/g, respectively. We compared the bacterial and fungal communities by analyzing the 16s rRNA (for bacteria) and ITS rDNA regions (for fungi). Our data revealed that the composition of fungal communities in rhizosphere soil of LZ+4 EI are higher than EF. In addition, the diversity and richness of fungal communities in root and rhizosphere soil of LQ+4 EI and LZ+4 EI are significantly higher than EF. Rhizosphere soil microbial community composition was higher than that in roots in LQ+4 and LZ+4. Peramine was significantly and positively correlated with the richness of the soil fungal community. Moreover, the principal component analysis (PCoA) results indicated that E. bromicola significantly influenced the community composition of root and rhizosphere soil microbes in both LQ+4 and LZ+4. Our results illustrate that E. bromicola can influence barley growth, peramine production and microbial communities associated with barley.

Project description:BACKGROUND:Plants have evolved intimate interactions with soil microbes for a range of beneficial functions including nutrient acquisition, pathogen resistance and stress tolerance. Further understanding of this system is a promising way to advance sustainable agriculture by exploiting the versatile benefits offered by the plant microbiome. The rhizosphere is the interface between plant and soil, and functions as the first step of plant defense and root microbiome recruitment. It features a specialized microbial community, intensive microbe-plant and microbe-microbe interactions, and complex signal communication. To decipher the rhizosphere microbiome assembly of soybean (Glycine max), we comprehensively characterized the soybean rhizosphere microbial community using 16S rRNA gene sequencing and evaluated the structuring influence from both host genotype and soil source. RESULTS:Comparison of the soybean rhizosphere to bulk soil revealed significantly different microbiome composition, microbe-microbe interactions and metabolic capacity. Soil type and soybean genotype cooperatively modulated microbiome assembly with soil type predominantly shaping rhizosphere microbiome assembly while host genotype slightly tuned this recruitment process. The undomesticated progenitor species, Glycine soja, had higher rhizosphere diversity in both soil types tested in comparison to the domesticated soybean genotypes. Rhizobium, Novosphingobium, Phenylobacterium, Streptomyces, Nocardioides, etc. were robustly enriched in soybean rhizosphere irrespective of the soil tested. Co-occurrence network analysis revealed dominant soil type effects and genotype specific preferences for key microbe-microbe interactions. Functional prediction results demonstrated converged metabolic capacity in the soybean rhizosphere between soil types and among genotypes, with pathways related to xenobiotic degradation, plant-microbe interactions and nutrient transport being greatly enriched in the rhizosphere. CONCLUSION:This comprehensive comparison of the soybean microbiome between soil types and genotypes expands our understanding of rhizosphere microbe assembly in general and provides foundational information for soybean as a legume crop for this assembly process. The cooperative modulating role of the soil type and host genotype emphasizes the importance of integrated consideration of soil condition and plant genetic variability for future development and application of synthetic microbiomes. Additionally, the detection of the tuning role by soybean genotype in rhizosphere microbiome assembly provides a promising way for future breeding programs to integrate host traits participating in beneficial microbiota assembly.

Dataset Information

Impact of salt and exogenous AM inoculation on indigenous microbial community structure in the rhizosphere of dioecious plant, Populus cathayana.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets