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Microorganisms Sep 2023Cuban rice cultivars INCA LP-5 and INCA LP-7 are widely distributed in Cuba and Caribbean countries. Although there are studies about rhizospheric bacteria associated...
Cuban rice cultivars INCA LP-5 and INCA LP-7 are widely distributed in Cuba and Caribbean countries. Although there are studies about rhizospheric bacteria associated with these cultivars, there are no reports about their seed-associated bacteria. This study aimed to isolate endophytic bacteria from rice seeds and select those with the greatest plant growth-promoting traits. A total of nineteen bacterial strains from the genera , , , and were isolated from the husk and endosperm of rice seeds. The strains sp. S5-1, sp. S5-38, and sp. S7-1 were classified as the most promissory to increase rice growth as they demonstrated the presence of multiple plant growth-promoting traits such as the production of auxins, phosphate, and potassium solubilization, the production of siderophores, and the inhibition of the phytopathogen . The inoculation of strains of sp. and spp. in rice improves the height, root length, fresh weight, and dry weight of the shoot and root after 21 days post-inoculation in hydroponic assays. This study constitutes the first report on Cuban rice cultivars about the presence of endophytes in seeds and their potential to promote seedling growth. sp. S5-1, sp. S5-38, and sp. S7-1 were selected as the more promising strains for the development of bio-stimulators or bio-inoculants for Cuban rice crops.
PubMed: 37764161
DOI: 10.3390/microorganisms11092317 -
Folia Microbiologica Feb 2024Endophytic microbes are plant-associated microorganisms that reside in the interior tissue of plants without causing damage to the host plant. Endophytic microbes can... (Review)
Review
Endophytic microbes are plant-associated microorganisms that reside in the interior tissue of plants without causing damage to the host plant. Endophytic microbes can boost the availability of nutrient for plant by using a variety of mechanisms such as fixing nitrogen, solubilizing phosphorus, potassium, and zinc, and producing siderophores, ammonia, hydrogen cyanide, and phytohormones that help plant for growth and protection against various abiotic and biotic stresses. The microbial endophytes have attained the mechanism of producing various hydrolytic enzymes such as cellulase, pectinase, xylanase, amylase, gelatinase, and bioactive compounds for plant growth promotion and protection. The efficient plant growth promoting endophytic microbes could be used as an alternative of chemical fertilizers for agro-environmental sustainability. Endophytic microbes belong to different phyla including Euryarchaeota, Ascomycota, Basidiomycota, Mucoromycota, Firmicutes, Proteobacteria, and Actinobacteria. The most pre-dominant group of bacteria belongs to Proteobacteria including α-, β-, γ-, and δ-Proteobacteria. The least diversity of the endophytic microbes have been revealed from Bacteroidetes, Deinococcus-Thermus, and Acidobacteria. Among reported genera, Achromobacter, Burkholderia, Bacillus, Enterobacter, Herbaspirillum, Pseudomonas, Pantoea, Rhizobium, and Streptomyces were dominant in most host plants. The present review deals with plant endophytic diversity, mechanisms of plant growth promotion, protection, and their role for agro-environmental sustainability. In the future, application of endophytic microbes have potential role in enhancement of crop productivity and maintaining the soil health in sustainable manner.
Topics: Endophytes; Bacteria; Bacillus; Basidiomycota; Ascomycota
PubMed: 37747637
DOI: 10.1007/s12223-023-01092-6 -
BMC Plant Biology Oct 2023In nature, beneficial bacteria triggering induced systemic resistance (ISR) may protect plants from potential diseases, reducing yield losses caused by diverse...
BACKGROUND
In nature, beneficial bacteria triggering induced systemic resistance (ISR) may protect plants from potential diseases, reducing yield losses caused by diverse pathogens. However, little is known about how the host plant initially responds to different beneficial bacteria. To reveal the impact of different bacteria on barley (Hordeum vulgare), bacterial colonization patterns, gene expression, and composition of seed endophytes were explored.
RESULTS
This study used the soil-borne Ensifer meliloti, as well as Pantoea sp. and Pseudomonas sp. isolated from barley seeds, individually. The results demonstrated that those bacteria persisted in the rhizosphere but with different colonization patterns. Although root-leaf translocation was not observed, all three bacteria induced systemic resistance (ISR) against foliar fungal pathogens. Transcriptome analysis revealed that ion- and stress-related genes were regulated in plants that first encountered bacteria. Iron homeostasis and heat stress responses were involved in the response to E. meliloti and Pantoea sp., even if the iron content was not altered. Heat shock protein-encoding genes responded to inoculation with Pantoea sp. and Pseudomonas sp. Furthermore, bacterial inoculation affected the composition of seed endophytes. Investigation of the following generation indicated that the enhanced resistance was not heritable.
CONCLUSIONS
Here, using barley as a model, we highlighted different responses to three different beneficial bacteria as well as the influence of soil-borne Ensifer meliloti on the seed microbiome. In total, these results can help to understand the interaction between ISR-triggering bacteria and a crop plant, which is essential for the application of biological agents in sustainable agriculture.
Topics: Hordeum; Pseudomonas; Endophytes; Bacteria; Iron; Soil; Plant Roots
PubMed: 37789272
DOI: 10.1186/s12870-023-04484-5 -
Journal of Basic Microbiology Nov 2023Bacterial panicle blight (BPB) disease is a dreadful disease in rice-producing countries. Burkholderia glumae, a Gram-negative, rod-shaped, and flagellated bacterium was... (Review)
Review
Bacterial panicle blight (BPB) disease is a dreadful disease in rice-producing countries. Burkholderia glumae, a Gram-negative, rod-shaped, and flagellated bacterium was identified as the primary culprit for BPB disease. In 2019, the disease was reported in 18 countries, and to date, it has been spotted in 26 countries. Rice yield has been reduced by up to 75% worldwide due to this disease. Interestingly, the biocontrol strategy offers a promising alternative to manage BPB disease. This review summarizes the management status of BPB disease using biological control agents (BCA). Bacteria from the genera Bacillus, Burkholderia, Enterobacter, Pantoea, Pseudomonas, and Streptomyces have been examined as BCA under in vitro, glasshouse, and field conditions. Besides bacteria, bacteriophages have also been reported to reduce BPB pathogens under in vitro and glasshouse conditions. Here, the overview of the mechanisms of bacteria and bacteriophages in controlling BPB pathogens is addressed. The applications of BCA using various delivery methods could effectively manage BPB disease to benefit the agroecosystems and food security.
Topics: Oryza; Plant Diseases
PubMed: 37348082
DOI: 10.1002/jobm.202300182 -
BMJ Case Reports Jun 2024Enteric gram-negative bacteria-associated peritoneal dialysis (PD) peritonitis is common. These organisms are such as , and species. Pantoea dispersa belongs to the...
Enteric gram-negative bacteria-associated peritoneal dialysis (PD) peritonitis is common. These organisms are such as , and species. Pantoea dispersa belongs to the order Enterobacterales, it has known benefits and a role in agricultural and environmental biotechnology. Pantoea dispersa, although still relatively rare, is being increasingly recognised to cause human infections. We are reporting a case of PD peritonitis caused by Pantoea dispersa in a kidney failure patient on continuous ambulatory peritoneal dialysis (CAPD). His peritonitis was treated well with intraperitoneal antibiotics and the patient can resume his CAPD therapy. The increasing reports of Pantoea dispersa-related human infections warrant concerns, both in immunocompromised and immunocompetent patients.
Topics: Humans; Pantoea; Male; Peritoneal Dialysis, Continuous Ambulatory; Peritonitis; Enterobacteriaceae Infections; Catheter-Related Infections; Anti-Bacterial Agents; Kidney Failure, Chronic; Middle Aged
PubMed: 38844354
DOI: 10.1136/bcr-2024-260878 -
Microbiology and Immunology Nov 2023Two Gram-negative facultative anaerobes were isolated from a sepsis patient with pancreatic cancer (strain PAGU 2156 ) and soil at the bottom of a pond (strain PAGU 2198...
Two Gram-negative facultative anaerobes were isolated from a sepsis patient with pancreatic cancer (strain PAGU 2156 ) and soil at the bottom of a pond (strain PAGU 2198 ), respectively. These two strains formed haloes around the colonies on chrome azurol S agar plates, indicating the production of siderophores. Two isolates assigned to the genus Pantoea based on the 16S rRNA gene were differentiated from established species by using polymorphic taxonomies. Phylogenetic analysis using four housekeeping genes (gyrB, rpoB, atpD, and infB) showed that strain PAGU 2156 is closely related to Pantoea cypripedii LMG 2657 (89.9%) or Pantoea septica LMG 5345 (95.7%). Meanwhile, strain PAGU 2198 formed a single clade with Pantoea rodasii DSM 26611 (93.6%) and Pantoea rwandensis DSM 105076 (93.3%). The average nucleotide identity values obtained from the draft genome assembly showed ≤90.2% between strain PAGU 2156 and closely related species and ≤81.5% between strain PAGU 2198 and closely related species. Based on various phenotypes, biochemical properties, and whole-cell fatty acid composition compared with related species, it was concluded that each strain should be classified as a new species of the genus Pantoea. In this manuscript, Pantoea ferrattrahens sp. nov. and Pantoea ferramans sp. nov. with strain PAGU 2156 (=NBRC 115930 = CCUG 76757 ) and strain PAGU 2198 (=NBRC 114265 = CCUG 75151 ) are proposed as each type strain.
Topics: Humans; Pantoea; Sequence Analysis, DNA; Siderophores; Phylogeny; RNA, Ribosomal, 16S; Ponds; Soil; Bacterial Typing Techniques; Fatty Acids; DNA, Bacterial; Nucleic Acid Hybridization
PubMed: 37740512
DOI: 10.1111/1348-0421.13097 -
Plant Physiology and Biochemistry : PPB Aug 2023A rhizobacterium, Pantoea conspicua, was examined against sunflower seedlings' growth under arsenate stress. Sunflower upon exposure to arsenate resulted in compromised...
A rhizobacterium, Pantoea conspicua, was examined against sunflower seedlings' growth under arsenate stress. Sunflower upon exposure to arsenate resulted in compromised growth that might be due to the accumulation of higher concentrations of arsenate and reactive oxygen species (ROS) in seedlings' tissues. The deposited arsenate led to oxidative damage and electrolyte leakage, making the sunflower seedlings vulnerable to compromise its growth and development. However, inoculation of sunflower seedlings with P. conspicua alleviated arsenate stress in host by initiating a multilayered defence mechanism. In fact, P. conspicua filtered out 75.1% of the arsenate from growth medium that were available to the plant roots in the absence of the said strain. To accomplish such activity, P. conspicua secreted exopolysaccharides as well as altered lignification in host roots. The arsenate (24.9%) that made its way to plant tissues was countered by helping the host seedlings to produce higher levels of indole acetic acid, non enzymatic antioxidants (phenolics and flavonoids) and antioxidant enzymes (catalase, ascorbte peroxidase, peroxidase, superoxide dismutase). As a result, ROS accumulation and electrolyte leakage were brought back to normal levels as observed in control seedlings. Hence, the rhizobacterium associated host seedlings achieved higher net assimilation (127.7%) and relative growth rate (113.5%) under 100 ppm of arsenate stress. The work concluded that P. conspicua alleviated arsenate stress in the host plants by imposing physical barrier as well as improving host seedlings' physiology and biochemistry.
Topics: Arsenates; Helianthus; Reactive Oxygen Species; Antioxidants; Oxidative Stress; Superoxide Dismutase; Seedlings; Plant Roots
PubMed: 37331076
DOI: 10.1016/j.plaphy.2023.107826 -
Frontiers in Microbiology 2023Copper hydroxide is a broad-spectrum copper fungicide, which is often used to control crop fungal and bacterial diseases. In addition to controlling targeted pathogens,...
Copper hydroxide is a broad-spectrum copper fungicide, which is often used to control crop fungal and bacterial diseases. In addition to controlling targeted pathogens, copper hydroxide may also affect other non-targeted microorganisms in the phyllosphere ecosystem. At four time points (before spraying, and 5, 10 and 15 days after fungicide application), the response of diseased and healthy tobacco phyllosphere microorganisms to copper hydroxide stress was studied by using Illumina high-throughput sequencing technology, and Biolog tools. The results showed that the microbiome communities of the healthy group were more affected than the disease group, and the fungal community was more sensitive than the bacterial community. The most common genera in the disease group were , , , , , , and ; while in the healthy group, these were , , , , and . After spraying, the alpha diversity of the fungal community decreased at 5 days for both healthy and diseased groups, and then showed an increasing trend, with a significant increase at 15 days for the healthy group. The alpha diversity of bacterial community in healthy and diseased groups increased at 15 days, and the healthy group had a significant difference. The relative abundance of and decreased while that of , , , and increased in the fungal communities of healthy and diseased leaves. The relative abundance of decreased first and then increased, while that of , and increased first and then decreased in the bacterial communities of healthy and diseased leaves. While copper hydroxide reduced the relative abundance of pathogenic fungi and , it also resulted in the decrease of beneficial bacteria such as Actinomycetes and , and the increase of potential pathogens such as and . After treatment with copper hydroxide, the metabolic capacity of the diseased group improved, while that of the healthy group was significantly suppressed, with a gradual recovery of metabolic activity as the application time extended. The results revealed changes in microbial community composition and metabolic function of healthy and diseased tobacco under copper hydroxide stress, providing a theoretical basis for future studies on microecological protection of phyllosphere.
PubMed: 37840714
DOI: 10.3389/fmicb.2023.1229294 -
Polymers Oct 2023A specific microorganism, uam8, was isolated from the ionic liquid (IL) Choline NTF and identified by molecular biology. A biodegradation study was performed at...
A specific microorganism, uam8, was isolated from the ionic liquid (IL) Choline NTF and identified by molecular biology. A biodegradation study was performed at osmolarity conditions (0.2, 0.6, 1.0 M). These had an important influence on the growth of the strain, exopolysaccharide (EPS) production, and biodegradation (1303 mg/L max production and 80% biodegradation at 0.6 M). These conditions also had an important influence on the morphology of the strain and its EPSs, but not in the chemical composition. The EPS (glucose, mannose and galactose (6:0.5:2)) produced at 0.6 M was further characterized using different techniques. The obtained EPSs presented important differences in the behavior of the emulsifying activity for vegetable oils (olive (86%), sunflower (56%) and coconut (90%)) and hydrocarbons (diesel (62%), hexane (60%)), and were compared with commercial emulsifiers. The EPS produced at 0.6 M had the highest emulsifying activity overall. This EPS did not show cytotoxicity against the tested cell line (<20%) and presented great advantages as an antioxidant (1,1-diphenyl-2-picryl-hydrazyl radical (DPPH) (85%), hydroxyl radical (OH) (99%), superoxide anion (O) (94%), chelator (54%), and antimicrobial product (15 mm). The osmolarity conditions directly affected the capacity of the strain to biodegrade IL and the subsequently produced EPS. Furthermore, the EPS produced at 0.6 M has potential for environmental applications, such as the removal of hazardous materials by emulsification, whilst resulting in positive health effects such as antioxidant activity and non-toxicity.
PubMed: 37836024
DOI: 10.3390/polym15193974 -
Microorganisms Jul 2023It is evident that legume root nodules can accommodate rhizobial and non-rhizobial bacterial endophytes. Our recent nodule microbiome study in peanuts described that...
It is evident that legume root nodules can accommodate rhizobial and non-rhizobial bacterial endophytes. Our recent nodule microbiome study in peanuts described that small nodules can harbor diverse bacterial endophytes. To understand their functional role, we isolated 87 indigenous endophytes from small nodules of field-grown peanut roots and characterized them at molecular, biochemical, and physiological levels. The amplified 16S rRNA genes and phylogenetic analysis of these isolates revealed a wide variety of microorganisms related to the genera , , , , , , , and . It was observed that 37% (100% identity) and 56% (>99% identity) of the isolates matched with the amplified sequence variants (ASVs) from our previous microbiome study. All of these isolates were tested for stress tolerance (high temperature, salinity, acidic pH) and phosphate (P) solubilization along with ammonia (NH), indole-3-acetic acid (IAA), 1-aminocyclopropane-1-carboxylate deaminase (ACCD), and siderophore production. The majority (78%) of the isolates were found to be halotolerant, thermotolerant, and acidophilic, and a few of them showed a significant positive response to the production of IAA, NH, siderophore, ACCD, and P-solubilization. To evaluate the plant growth promotion (PGP) activity, plant and nodulation assays were performed in the growth chamber conditions for the selected isolates from both the non-rhizobial and rhizobial groups. However, these isolates appeared to be non-nodulating in the tested conditions. Nonetheless, the isolates 2 (), 17 (), 21 (), 33o (), and 77 ( sp.) showed significant PGP activity in terms of biomass production. Our findings indicate that these isolates have potential for future biotechnological applications through the development of biologicals for sustainable crop improvement.
PubMed: 37630501
DOI: 10.3390/microorganisms11081941