Hypsizygus marmoreus has become one of the most popular edible mushrooms due to its high nu-tritional and economic value. Previous researchers found that Serratia odorifera could promote the growth of H. marmoreus by producing and secreting some of its inducers. However, the specific mechanism of action was still unclear. In this study, we found that exogenous addition of sterile fermentation filtrate (HZSO-1), quorum sensing (QS signaling molecules, 3-oxo-C6-HSL, cy-clo(Pro-Leu), and cyclo(Tyr-Leu) could significantly promote the growth of H. marmoreus, increase the number of clamp junctions, and the diameter of mycelium (P < 0.05). In addition, non-targeted metabolomic analysis has revealed that 706 metabolites were detected in the treated group. Of these, 307 metabolites were significantly different (P < 0.05). Compared with the control, 54 and 86 metabolites were significantly increased and decreased in the HZSO-1 group, respec-tively (P < 0.05). We speculated that the sterile fermentation filtrate of S. odorifera could mediate the carbohydrate and amino acid metabolism of H. marmoreus by influencing the pentose phosphate pathway (PPP) to increase the energy supply for the growth and development of the mycelium. The above results will further reveal the growth-promoting mechanism of S. odorifera on H. mar-moreus.

A large number of studies have indicated that plant community modulate the yield, improve growth and promote development of host plants, and among them rhizosphere growth-promoting bacteria play an important role in increasing crop yield. Bacteria benefit from the plant nutrients provided by the roots, but plants can benefit from their rhizobacteria as well. Rhizobia are considered as the most important candidate for plant growth promotion in comparison with rhizobacteria due to their endophytic nature and nitrogen fixing ability. They can also provide auxins which play a notable function in plant growth and plant-microbe interactions. Bacillus spp., the sporulating Gram-positive bacteria, have important roles in plant growth promotion and induction of systemic resistance. Pseudomonas are Gram-negative aerobic chemoheterotroph and are usually found in the environment. Streptomyces are important groups of soil bacteria from the actinomycetes family. Most of them are efficient rhizosphere and rhizoplane colonizers, and they can also be endophytes colonizing inner tissues of host plants. The present review aims to present the most up-to-date findings and results regarding the effects of plant growth promoting bacteria on yield of different crops, especially sorghum. Furthermore, the mechanisms of the actions of different bacteria briefly illustrated, aiming to present future needs to be addressed in sustainable crop production. Plant growth promoting rhizobacteria inoculation with different plants or treating plants with microbe-to-plant signal constituents can be an effectual technique to stimulate crop growth. They are also active in protecting crops from phytopathogens and environmental stress, plant pathogens and they have positive roles in nutrient cycling.

The implementation of phytoremediation strategies under arid and semi-arid climate requires the use of appropriate plant species capable of withstanding multiple abiotic stresses. In this study, we assessed the combined effects of organo-mineral amendments and microbial inoculants on chemical and biological properties of mine tailings, as well as on growth of native plant species under drought stress conditions. Plants were cultivated in pots containing 1 kg of a mixture of mine tailings and topsoil (i.e. pre-mined superficial soil) in a 60:40 ratio, 6% marble sludge and 10% sheep manure. Moreover, a consortium of four drought-resistant rhizobacteria was inoculated. Three irrigation levels were applied: well-watered, moderate water deficit, and severe water deficit, corresponding to 80%, 45%, and 30% of field capacity, respectively. The addition of topsoil and organo-mineral amendments to mine tailings significantly improved their chemical and biological properties, which were further enhanced by bacterial inoculation and plants’ establishment. Water stress negatively impacted enzymatic activities in amended tailings, resulting in a significant decrease of acid and alkaline phosphatases, urease, and dehydrogenase activities. Similar results were obtained for bacteria, fungi and actinomycetes abundance. PGPR inoculation positively influenced the availability of phosphorus, total nitrogen, and organic carbon, while increased alkaline phosphatase, urease (by about 10%) and dehydrogenase activities (by 50%). The rhizosphere of P. harmala showed the highest enzymatic activity and number of culturable microorganisms, especially in inoculated treatments. Severe water deficit has nega-tively affected plant growth, leading to a 40% reduction in shoot biomass of both Atriplex halimus and Pennisetum setaceum compared to well-watered plants. Peganum harmala showed greater tolerance to water stress, as corroborated by the lower decreases observed in root and shoot length and dry weight compared to well-watered plants. The use of bioinoculants mitigated the negative effects of drought on P. harmala shoot biomass, resulting in an increase of up to 75% in the aerial biomass in plants exposed to severe water deficit. In conclusion, the results suggest that the combination of organo-mineral amendments, PGPR inoculation and P. harmala represents a promising approach to enhance the phytoremediation of metal-polluted soils under semi-arid conditions.

The world’s population is increasing and so are agricultural activities to match the growing demand for food. Conventional agricultural practices generally employ artificial fertilizers to increase crop yields, but these have multiple environmental and human health effects. For decades, environmentalists and sustainability researchers have focused on alternative crop fertilization mechanisms to address these challenges, and biofertilizers have constantly been researched, recommended, and even successfully-adopted for several crops. Biofertilizers are microbial formulations made of indigenous plant growth-promoting rhizobacteria (PGPR) which can naturally improve plant growth either directly or indirectly, through the production of phytohormones, solubilization of soil nutrients, and production of iron-binding metabolites; siderophores. Biofertilizers, therefore, hold immense potential as tools for sustainable crop production especially in the wake of climate change and global warming. Despite the mounting interest in this technology, their full potential has not yet been realized. This review updates our understanding of the PGPR biofertilizers and sustainable crop production. It evaluates the history of these microbial products, assesses their present state of utilization, and also critically propounds on their future prospects for sustainable crop production. Such information is desirable to fully evaluate their potential and can ultimately pave the way for their increased adoption for crop production.

Plant growth-promoting rhizobacteria (PGPR) are members of the plant rhizomicrobiome that enhance plant growth and stress resistance by increasing nutrient availability to the plant, producing phytohormones or other secondary metabolites, stimulating plant defense responses against abiotic stresses and pathogens, or fixing nitrogen. The use of PGPR to increase crop yield with minimal environmental impact is a sustainable and readily applicable replacement for a portion of chemical fertilizer and pesticides required for the growth of high-yielding varieties. Increased plant health and productivity have long been gained by applying PGPR as commercial inoculants to crops, although with uneven results. The establishment of plant-PGPR relationships requires the exchange of chemical signals and nutrients between the partners, and polyamines (PAs) are an important class of compounds that act as physiological effectors and signal molecules in plant-microbe interactions. In this review we focus on the role of PAs in interactions between PGPR and plants. We describe the basic ecology of PGPR and production and function of PAs in them and in the plants with which they interact. We examine the metabolism and the roles of PAs in PGPR and plants individually and during their interaction with one another. Lastly, we describe some directions for future research.

Microbial-based biostimulants containing arbuscular mycorrhizal fungi (AMF), Trichoderma fungi and plant growth-promoting rhizobacteria (PGPR) have been applied in an open-field tomato cultivation. A two-years field experiment (2020-2021) was performed in Southern Italy on “Heinz 1534” processing tomato hybrid, using three commercial formulations characterized by different microbial consortia (MIC: Glomus spp., Rhizophagus spp., Bacillus spp., Streptomyces spp., Pichia spp., Trichoderma spp.; EKO: Glomus spp., Bacillus spp., Streptomyces spp., Pseudomonas spp., Arthrobotrys spp., Monacrosporium spp., Paecilomyces spp., Myrothecium spp., Trichoderma spp.; FID: Glomus spp., Bacillus spp., Trichoderma spp.) and comparing them to untreated control (CTRL). The effect of growing season and microorganism-based treatments on yield, technological traits and functional quality of tomato fruits was assessed. The year of cultivation (Y) affected yield (with lower fruit weight, higher marketable to total yield ratio and higher % of total defected fruits in 2020), and technological components (higher dry matter, total acidity, total soluble solids in 2020). During the first year of the trial, all evaluated treatments (MIC, EKO and FID) enhanced soluble solids content by 10%, on average, compared to CTRL. Sucrose and lycopene contents were influenced both by the microbial-based treatments and the growing season (greater values found in 2021 with respect to the first year). Y factor also significantly affected all evaluated metabolites contents, except for tyrosine, essential (EAA) and branched-chain (BCAAs) amino acids. Over two years of field trial, FID biostimulant enhanced the contents of proteins (+53.71%), alanine (+16.55%), aspartic acid (+31.13%), γ-aminobutyric acid (+76.51%), glutamine (+55.17%), glycine (+28.13%), monoethano-lamine (+19.57%), total amino acids (+33.55), essential amino acids (+32.56%) and branched-chain amino acids (+45.10%) compared to the untreated control. Our findings highlighted the valuable effect of FID microbial inoculant in boosting several primary metabolites (proteins and amino acids) in the fruits of processing tomato crop grown under Southern Italy environmental condi-tions, although no effect on yield and its components was appreciated.

Activation of the NLRP3 inflammasome plays a crucial role in innate immune response. During cell division, the NLRP3 inflammasome activation must be strictly controlled. Here, we discovered the anaphase promoting complex subunit 10 (Anapc10, APC10), a substrate recognition protein of the anaphase promoting complex/cyclosome (APC/C), is a critical mediator of the NLRP3 inflammasome activation. APC10 protein interacts with NLRP3, and co-localizes with NLRP3 protein in the cytoplasm. During interphase, APC10 interacts with NLRP3 to promote the NLRP3 inflammasome activation. During mitosis, APC10 disassociates from the NLRP3 inflammasome to inhibit the inflammatory responses. This study reveals a distinct mechanism by which APC10 serves as a switch of the NLRP3 inflammasome activation during cell cycle.

A new quinazolinone alkaloid, named peniquinazolinone A (1), as well as eleven known compounds, 2-(2-hydroxy-3-phenylpropionamido)-N-methylbenzamide (2), viridicatin (3), viridicatol (4), (±)-cyclopeptin (5a/5b), dehydrocyclopeptin (6), cyclopenin (7), cyclopenol (8), methyl-indole-3-carboxylate (9), 2,5-dihydroxyphenyl acetate (10), methyl m-hydroxyphenylacetate (11), conidiogenone B (12), was isolated from the endophytic Penicillium sp. HJT-A-6 derived from the stem of Rhodiola tibetica. The chemical structures of all compounds were elucidated by comprehensive spectroscopic analysis, including 1D, 2D NMR and HRESIMS. The absolute configuration at C-13 of peniquinazolinone A (1) was established by applying the modified Mosher’s method. Compounds 2, 3, and 7 exhibited an optimal promoting effect on the seed germination of Rhodiola tibetica at a concentration of 0.01 mg/mL, while the optimal concentration for compounds 4 and 9 to promote Rhodiola tibetica seed germination is 0.001 mg/mL. Compound 12 showed optimal seed-germination-promoting activity at a concentration of 0.01 mg/mL. Compared with the positive drug 6-benzyladenine (6-BA), compounds 2, 3, 4, 7, 9, and 12 could extend the seed-germination period of Rhodiola tibetica up to the 11th day.

Strawberry root rot caused by Neopestalotiopsis clavispora is one of the main diseases of strawberry and significantly impacts the yield and quality of strawberry fruit. There are now no effective control techniques available except for fungicide sprays, which may directly impact consumers. Biological control is becoming an alternative method for the control of plant diseases to replace or decrease the application of traditional synthetic chemical fungicides. Trichoderma is widely used as a biological agent for controlling strawberry root rot. In order to provide resources for screening the highly effective biocontrol fungus for controlling strawberry root rot caused by Neopestalotiopsis clavispora, the biocontrol mechanism,the control effects of Trichoderma asperellum CMT10 against strawberry root rot and growth-promoting effects on strawberry seedlings were investigated by plate culture, microscopy observation and root drenching methods.The results showed that CMT10 had obvious competitive, antibiotic and hyperparasitism effects on Neopestalotiopsis clavispora CMGF3. The CMT10 could quickly occupy nutritional space, and the inhibition rates of CMT10 against CMGF3 in confrontation culture on 7 d was 65.49%. The inhibition rates of volatile metabolite and fermentation metabolite produced by CMT10 against CMGF3 were 79.67% and 69.84%, respectively. The mycelium of strain CMT10 can act as hyperparasites by making contacting, winding and penetrating hyphae of CMGF3. Pot experiment showed that the biocontrol efficacy of CMT10 on strawberry root rot caused by Neopestalotiopsis clavispora was 63.00%. CMT10 had obvious promotion effect on strawberry growth, the plant height, root length, total fresh weight, root fresh weight, stem fresh weight and root dry weight, with the promotion rates were 20.09%, 22.39%, 87.11%, 101.58%, 79.82% and 72.33%, respectively. Overall, this study showed the ability of Trichoderma asperellum CMT10 to control strawberry root rot and their potential to develop as novel biocontrol agents to replace chemical fungicides for eco-friendly, sustainable agriculture.

Salinity is one of the major factors responsible for the deterioration of soils, making them unsuitable for agriculture. The application of halotolerant and halophilic plant growth promoting bacteria (PGPR: Plant Growth Promoting Rhizobacteria) with biological control activities as an inoculant of cultivated plants offers a biological alternative to the use of agrochemicals, particularly when subjected to salt stress. In this perspective, 70 bacterial strains were isolated from saline soils (sebkha) in arid and semi-arid areas of eastern Algeria. Three isolates were selected based on their ability to produce bioactive molecules allowing them to promote plant growth, such as hydrolytic enzymes, indole acetic acid, HCN, NH3, etc. Two of these isolates belong to the genus Serratia and the third is a halophilic Halomonas bacteria. These bacteria were identified based on the 16S rDNA sequence. Antagonism tests against phytopathogenic fungi were carried out. The identification of the antifungal molecules produced by these bacteria was done by high performance liquid chromatography. These bacteria are capable of inhibiting mycelial development against phytopathogenic fungi with rates reaching 80.67% against Botrytis cinerea, 76.22% against Aspergillus niger and 66.67% against Fusarium culmorum for Serratia sp. The strain Halomonas sp. inhibited mycelial growth by production of volatile substances of Aspergillus niger at 71.29%, Aspergillus flavus at 75.49% and Penicillium glabrum at a rate of 72.22%. The identification by HPLC of the antifungal molecules produced by these three bacteria reveals that they are polyphenols, which makes these strains the first rhizobacteria capable of producing phenolic compounds. Finally, pot tests to determine the effectiveness of these strains in promoting wheat growth under salinity stress (125 mM, 150 mM and 200 mM) were carried out. The results revealed that a consortium of two isolates (Serratia sp. and Halomonas sp.) performed best at 125 mM. But, at higher concentrations it was the halophilic bacteria Halomonas sp which gave the best result. In all cases, there was a significant improvement in the growth of wheat seedlings inoculated with the bacteria, compared to non-inoculated controls.

Streptococcus thermophilus is widely used as a starter culture in the dairy industry and has garnered attention as a beneficial bacterium owing to its health-promoting functionalities in humans. In this study, the probiotic potential of S. thermophilus MCC0200, isolated from a dairy product, was investigated through a combinatorial approach of in-vitro and in-silico studies. MCC0200 demonstrated the ability to survive harsh gastro-intestinal transit (GIT), adhere to intestinal mucosa and exert health-promoting traits in in-vitro studies. These findings were corroborated with in-silico evidence, wherein MCC0200 genome harboured genes associated with tolerance to GIT conditions, intestinal adhesion and colonization. Genome mapping also highlighted the ability of MCC0200 to produce compounds advantageous for host (folate, bacteriocins), to release enzymes that can reinforce the host ability (antioxidative enzymes), to metabolize food components that can be harmful to sensitive people (lactose). MCC0200 also demonstrated a positive effect on reducing cholesterol levels, proving to be a potential candidate for food and pharmaceutical applications. Absence of transmissible antibiotic resistance genes and virulence genes underscored the GRAS nature of MCC0200. This study explored the potential of Streptococcus thermophilus for its probable applications as a probiotic beyond the dairy industry.

The development of multiple drug resistant (MDR) cancer all too often signals the need for alternative toxic therapy or palliative care. Our recent in vivo and in vitro studies using canine MDR lymphoma cancer cells demonstrated that the Anaphase Promoting Complex (APC) is impaired in MDR cells compared to normal canine control and drug sensitive cancer cells. Here, we sought to establish whether this phenomena is a generalizable mechanism independent of species, malignancy type or chemotherapy regime. To test the association of blunted APC activity with MDR cancer behavior, we used matched parental and MDR MCF7 human breast cancer cells, and a patient derived xenograft (PDX) model of human breast cancer. We show that APC activating mechanisms, such as APC subunit 1 (APC1) phosphorylation and CDC27/CDC20 protein associations, are reduced in MCF7 MDR cells when compared to chemosensitive matched cell lines. Consistent with impaired APC function in MDR cells, APC substrate proteins failed to be effectively degraded. Similar to our previous observations in canine MDR lymphoma cells, chemical activation of the APC using Mad2 Inhibitor-1 (M2I-1) in MCF7 MDR cells enhanced APC substrate degradation and resensitized MDR cells in vitro to the cytotoxic effects of the alkylating chemotherapeutic agent, Doxorubicin (DOX). Using cell cycle arrest/release experiments we show that chemo-sensitive and -resistant MCF7 cells progress through the cell cycle at similar rates, but mitosis is delayed in MDR cells with elevated substrate levels. When treated with M2I-1, MDR cells progress through mitosis at a faster rate that coincides with reduced levels of APC substrates. In our PDX model, mice growing a clinically-MDR human breast cancer tumor show significantly reduced tumor growth when treated with M2I-1, with evidence of increased DNA damage and apoptosis. Thus, our results strongly support the hypothesis that APC impairment is a driver of aggressive tumor development and that targeting the APC for activation has the potential for meaningful clinical benefits in treating recurrent cases of MDR malignancy.

Cercospora beticola Sacc. is an ascomycete pathogen that causes Cercospora leaf spot in sugar beets (Beta vulgaris L.) and other related crops. The disease symptoms are characterized by circular lesions with an ash-gray centre and dark brown to purple margins on the leaves. It can lead to significant yield losses if not effectively managed. This study aims to characterize and assess the impact of bacterial biological control agents against C. beticola. Following a dual-culture screening, 18 bacteria exhibiting over 50% inhibition were selected, with six of them demonstrating more than 80% control. Identification of the bacteria was carried out through sequencing of the16S rDNA, revealing potentially 12 species belonging to six genera including Bacillus which was represented by four species. Additionally, the bacteria underwent in-depth characterization of biochemical and molecular properties, as well as plant-growth promotion. PCR detection of genes responsible for producing antifungal metabolites revealed that 83%, 78%, 89%, and 56% of the selected bacteria possessed the bacillomycin, iturin, fengycin, and surfactin encoding genes, respectively. Infrared spectroscopy analysis confirmed the presence of lipopeptide structure in the bacteria supernatant filtrate. Subsequently, the bacteria were assessed for their effect on sugar beet plants in controlled conditions. The bacteria exhibited notable capabilities, promoting growth in both roots and shoots, resulting in significant increases in root length, weight, and shoot length. The field experiment with four bacterial candidates demonstrated good performance against C. beticola compared to difenoconazole fungicide. These bacteria played a significant role in disease control, achieving a maximum efficacy of 77.42%, slightly below the 88.51% efficacy attained by difenoconazole. Additional field trials are necessary to verify the protective and growth-promoting effects of these candidates, whether applied individually, combined in consortia, or integrated with chemical inputs in sugar beet crop production.

The use of plant-based and microorganism-based biological inputs is a sustainable agricultural practice, promoting a suitable and better utilization of non-renewable resources in the environment. The benefits of using microorganisms are associated with both direct and indirect mechanisms, primarily related to improvements in nutrient absorption and availability, as well as plant growth. The main benefits of using biochemical pesticides are the promotion of sustainability and the management of resistance. Although the use of microorganisms and botanical metabolites is a promising agricultural alternative, it is still primarily concentrated in grain crops. However, due to the wide range of mechanisms of action of plant-based and microorganism-based biological inputs, there is an opportunity to expand their use in agriculture. In the Brazilian biological inputs market, various terminologies have been used to characterize biological-based products, with many of these terms being employed incorrectly and sometimes conflicting with the country’s legislation. Therefore, this review presents the classes of biological inputs and the application and evolution of the plant-based and microbiological-based product market in different crops in Brazil.

The role of calcium ions (Ca2+) is extensively documented and comprehensively understood in eukaryotic organisms. Nevertheless, emerging insights, primarily derived from studies on human pathogenic bacteria, suggest that this ion also holds a pivotal role in prokaryotes. In this review, our primary focus will be on unraveling the intricate Ca2+ toolkit within prokaryotic organisms, with particular emphasis on its implications in plant growth promoting rhizobacteria (PGPR). To pinpoint and identify homologues of Ca2+ channels, pumps, exchangers, and Calcium-Binding Proteins (CaBPs) we undertook an in silico exploration in the genomes of four distinct PGPR strains using as query prokaryotic sequences that were experimentally confirmed to play a role in regulating intracellular calcium concentration ([Ca2+]i) or sensing and transducing this essential cation. These investigations were conducted in Pseudomonas chlororaphis subsp. aurantiaca SMMP3, P. donghuensis SVBP6, Pseudomonas sp. BP01, and Methylobacterium sp. 2A. which have been isolated and characterized within our research laboratories. We also present experimental data to evaluate the influence of exogenous Ca2+ concentrations ([Ca2+]ex) on the growth dynamics of these isolated strains

Bacterial endophytes (120) were isolated from six halophytes (Distichlis spicata, Cynodon dactylon, Eragrostis obtusiflora, Suaeda torreyana, Kochia scoparia, and Baccharis salicifolia). These halophiles were molecularly identified and characterized with or without NaCl conditions. Characterization was based on tests such as indole acetic acid (IAA), exopolysaccharides (EPS), and siderophores (SID) production; solubilization of phosphate (P), potassium (K), zinc (Zn), and manganese (Mn); mineralization of phytate; enzymatic activity (acid and alkaline phosphatase, phytases, xylanases, and chitinases) and mineralization/solubilization mechanisms involved (organic acids and sugars). Eleven halophiles (tolerated NaCl 2.5 M) were identified as Oceanobacillus sp. (1), Bacillus sp. (2), Nesterenkonia sp. (3), Bacillus velezensis (4), Halobacillus sp. (5), Oceanobacillus sp. (6), B. velezensis (7) Halomonas sp. (8), B. pumilus (9), Pseudomonas sp. (10) and Oceanobacillus sp. (11). Biochemical responses of nutrient solubilization and enzymatic activity varied between bacteria and the presence of NaCl. Organic acids were involved in P-mineralization and nutrient solubilization. Tartaric acid was common in the solubilization of P, Zn, and K. Maleic and vanillic acid were only detected in Zn and K solubilization, respectively. Moreover, sugars appeared to be involved in the solubilization of nutrients; fructose was detected in solubilization tests. Therefore, these bacteria should be tested as a consortium to mitigate saline stress in glycophytes under a global climate change scheme that threatens to exacerbate soil salinity.

The targeted application of plant growth promoting rhizobacteria (PGPR) provides the key for a future sustainable agriculture with reduced pesticide application. PGPR interaction with the indigenous microbiota is poorly understood but essential to develop reliable applications. Therefore, Stenotrophomonas rhizophila SPA-P69 was applied as seed coating and in combination with a fungicide based on the active ingredients fludioxonil, metalaxyl-M, captan and ziram. Plant performance and rhizosphere composition of treated and non-treated maize plants of two field trials were analyzed. Plant health was significantly increased by treatment; however overall corn yield was not changed. By applying high-throughput amplicon sequencing of the 16S rRNA and the ITS genes, the bacterial and fungal changes in the rhizosphere due to different treatments were determined. Despite treatments had a significant impact on the rhizosphere microbiota (9- 12%), the field site was identified as main driver (27- 37%). Soil microbiota composition from each site was significantly different, which explains the site-specific effects. In this study we were able to show first indications how PGPR treatments increase plant health via microbiome shifts in a site-specific manner. This way first steps towards a detailed understanding of PGPRs and developments of consistently efficient applications in diverse environments are set.

The soil and groundwater of Bhagobangola I block of Murshidabad district, West Bengal, India is severely arsenic contaminated. A bacterium was isolated from the garden soil of Mahishasthali village, which could tolerate 36.49 mM arsenic (III), 280.44 mM arsenic (V) and 63 mM chromium (III), which makes it arsenic (III & V) and chromium (III) hyper-tolerant bacterium. The growth pattern of this bacterium does not show much alteration in presence of 10 mM arsenic (III) and chromium (III), emphasizing its resistance to these heavy metals. Scanning electron microscopy depicted the size of this bacterium to be ~1.45 µm. 16S rDNA sequencing followed by subsequent phylogenetic analysis established the identity of this bacterium as Microbacterium paraoxydans. The bacterium is capable of bioremediation of arsenic and showed 30.8% & 22.6%, and 35.2% and 30.5% of bioremediation over a period of 24 and 48 hours in 1 mM and 4 mM arsenite, respectively. Microbacterium paraoxydans also exhibit plant growth promoting properties like nitrogen fixation, phosphate solubilization, indole-3-acetic acid production and production of siderophores. Therefore, the heavy metal resistance, bioremediation potential and plant growth promoting potential of the bacterium could be utilized not only for reduction of arsenic toxicity in soil and groundwater but also for plant growth promotion by using it as a biofertilizer.

Phytoremediation, a method of phytomanagement using the plant holobiont to clean up polluted soils, is particularly effective for degrading organic pollutants, such as alkanes and polycyclic aromatic hydrocarbons (PAHS). However, the respective contributions of host plants and their associated microbiota within the holobiont to the efficiency of phytoremediation is poorly understood. Identification of plant-associated bacteria capable of efficiently utilizing these compounds as carbon source while stimulating plant-growth, is a keystone for phytomanagement engineering in order to improve the efficiency of pollutant removal. In this study, we sampled the rhizosphere and the surrounding bulk soil of Salix purpurea and Eleocharis obusta from the site of a former petrochemical plant in Varennes, QC, Canada. Our objectives were to: (i) isolate and identify indigenous bacteria inhabiting these biotopes; (ii) assess the ability of isolated bacteria to utilize alkanes (dodecane and hexadecane) and PAHs (naphthalene, phenanthrene and pyrene) as the sole carbon source, and (iii) determine the plant growth-promoting (PGP) potential of the isolates using five key traits. A total of 438 morphologically different bacterial isolates were obtained, purified, preserved and identified through PCR and 16S rRNA gene sequencing. Identified isolates represent 62 genera, including taxa such as Acinetobacter, Arthrobacter, Bacillus, Enterobacter, Nocardia, Pseudomonas, Rhodococcus, Streptomyces and Variovorax. Approximately, 32% of bacterial isolates, including Arthrobacter, Pseudomonas, Streptomyces, Enterobacter, Nocardia, Acinetobacter and Microbacterium, were able to utilize all five different hydrocarbons compounds. Additionally, 5% of tested isolates belonging to genera Pseudomonas, Acinetobacter, Serratia, Klebsiella, Microbacterium, Bacillus and Stenotrophomonas possessed all five of the tested PGP functional traits. This culture collection of diverse, petroleum-hydrocarbon degrading bacteria, with multiple PGP traits, represents a valuable resource for future use in environmental bio- and phyto-technology applications, including phytoremediation of petroleum hydrocarbons contaminated soils and phytomanagement of anthropized areas.

Endophytic bacteria, especially those participate in nitrogen fixation, play critical roles in supplying essential nutrients for legume plant growth. Compared to the numerous bacterial microbiome reports targeting legume roots and nodules, little is known about embryonic bacteria that facilitate plant nutrient utilization after seed germination. Here, we collected and investigated endophytic bacterial microbiomes in edible pea (Pisum sativum) embryos using five representative cultivars and a pea sprout control. Twenty-six nitrogen-fixing bacteria (NFBs) were isolated from pea embryos, with three strains found in fresh pea (FGP) and snow pea (SP) exhibiting the strongest nitrogenase activity. Some NFB isolates are also potassium-solubilizing bacteria (KSBs) or phosphorus-solubilizing bacteria (PSBs) utilizing inorganic and/or organic phosphorus. All 26 NFBs showed variable levels of indole-3-acetic acid (IAA) secretion. The nutrient-solubilizing NFBs identified in our research are valuable resources for biofertilizer development. At the microbiome level, high-throughput 16S ribosomal RNA (rRNA) sequencing of 40 bacterial collections from pea embryos revealed similar community structures and species abundances and diversities in most samples. Our embryo-derived endophytic bacterial pool provides a microbiome platform for seed dormancy and germination research of edible peas.

Soil contamination with petroleum hydrocarbons (PHCs) has become a global concern in the word due to intensification of industrial activities. This creates a serious environmental issue, therefore there is a need to find solutions, including application of efficient remediation technologies, or to improve current techniques. Rhizoremediation is a sub-category of the phytoremediation which refers to Phytomanagement that uses plants and their associated microbiota. These green technologies have received a global attention as a cost-effective and possible efficient remediation technique that can be applied to cleanup PHCs-polluted soils. The mechanism of rhizoremediation process is that plant roots stimulate soil microbes to mineralize organic contaminants to H2O and CO2. However, this multipartite interaction is much complex because many biotic and abiotic factors can influence microbial processes in the soil, making the efficiency of rhizoremediation unpredictable. This review reports the progress made on rhizoremediation approaches that can overcome the limitations and improve the efficiency of PHCs-contaminated soils. The addressed approaches in this review include: 1) selecting plants with desired characteristics suitable for rhizoremediation, 2) the exploitation and manipulation of plant microbiome by using inoculant containing plant growth-promoting rhizobacteria (PGPR) or hydrocarbon-degrading microbes, or a combination of both types of organisms, and 3) enhancement of the understanding of how host-plant assembles a beneficial microbiome, and how it functions, under pollutant stress.

In the last decades, intensive crop management has involved excessive use of pesticides or fertilizers, compromising environmental integrity and public health. Accordingly, there has been worldwide pressure to find an eco-friendly and safe strategy to ensure agricultural productivity. Recently, Plant Growth-Promoting (PGP) rhizobacteria are receiving increasing attention as suitable biocontrol agents against agricultural pests. In the present study, 22 spore-forming bacteria were selected among a salt-pan rhizobacteria collection for their PGP traits and their antagonistic activity against the plant pathogen fungus Macrophomina phaseolina. Based on the higher antifungal activity, strain RHFS10, identified as Bacillus vallismortis, was furtherly examined and cell-free supernatants assays, column purification, and tandem mass spectrometry employed to purify and preliminarily identify the antifungal metabolites. Interestingly, the minimum inhibitory concentration assessed for the fractions active against M. phaseolina, resulted 10 times lower and more stable than the one estimated for the commercial fungicide pentachloronitrobenzene. These results suggest the use of B. vallismortis strain RHFS10 as a potential Plant Growth Promoting Rhizobacteria to efficiently control phytopathogenic fungus M. phaseolina, in alternative to chemical pesticides.

Knowledge of the agricultural soil microbiota, of the microbial consortia that comprise it, and the promotion of agricultural practices that maintain and encourage them, is a promising way to improve soil quality for sustainable agriculture and to provide food security. Although numerous studies have demonstrated the positive effects of beneficial soil microorganisms on crop yields and quality, the use of microbial consortia in agriculture remains low. Microbial consortia have more properties than an individual microbial inoculum, due to the synergy of the microorganisms that make them up. This review describes the main characteristics, ecosystem functions, crop benefits and biotechnological applications of microbial consortia composed of arbuscular mycorrhizal fungi, plant growth promoting bacteria and actinobacteria, to promote the restoration of agricultural soils and, consequently, the quality and health of agricultural crops. The aim is to provide knowledge that will contribute to the development of sustainable and sufficiently productive agriculture, which will adapt in a good way to the pace of the growing human population and to climate change.

Paenibacillus sp. tmac-D7 was isolated from coastline growing Trifolium macraei (double-head clover) root nodules from Bodega Bay, California. The draft genome is 5,567,337 bp with a G+C% of 52.4%, an N50 of 114,261 bp, and 5,282 predicted protein-coding genes. Paenibacillus, while found in many other environments, is frequently isolated from root nodules, with many acting as plant pathogen antagonists. Paenibacillus sp. tmac-D7 is the first genome of a non-rhizobial endophyte isolate from wild Trifolium macraei (double-head clover).

Despite several studies on learner-to-teacher workplace violence and harassment, the problem persists in some South African schools. Learner-to-teacher violence and harassment is a form of workplace violence and harassment as schools are workplaces for teachers. Learner-to-teacher violence and harassment is therefore an important occupational health and safety issues for teachers. The employer is obliged to provide a safe working environment for the teachers to enable quality teaching and learning in the schools. The purpose of this interpretative phenomenological study was to explore and describe the lived experiences of high school teachers who have been targets of workplace violence and harassment perpetrated by learners at selected schools in Limpopo province of South Africa. Many teachers were willing to share their lived-experiences but due to data saturation, only eleven participated after being selected through purposive sampling from seven high schools under a particular circuit. Research ethics of voluntary participation, informed consent, ethical clearance and gatekeeper permission were observed. Data was collected through semi-structured interviews using an interview guide. Interviews were audio-taped, and field notes were also taken. Voice recordings were transcribed verbatim and analysed using interpretative phenomenological analysis into themes and sub-themes. Findings were confirmed by an independent coder to achieve trustworthiness. Teachers experienced physical workplace violence and harassment, verbal workplace violence and harassment as well as nonverbal workplace violence and harassment from learners. Learner-to-teacher workplace violence and harassment affects teachers emotionally and in turn affects quality teaching and learning in the schools. Some teachers propose involvement of community policing forum, strengthening of School Governing Bodies as well as reducing overcrowding in the classroom as possible solutions to deal with learner-to-teacher bullying.

Background: Physical and mental health of corporate employees is equally important, especially in international salespeople in the in vitro diagnostic (IVD) medical device industry. The rapid growth of the IVD market is driven by the increasing prevalence of chronic and infectious diseases. This study aims to identify the association of socio-demographic, occupational, organizational, and psychosocial factors with mental health outcomes for depression, anxiety, and somatic symptoms in Chinese IVD international salespeople. Methods: The study was a cross-sectional survey of ISs in IVD companies officially registered in China. An online survey was designed to collect data through email contact with IVD companies and social media between August 2022 and March 2023. Measured factors included effort-reward imbalance (ERI), health-promoting leadership (HPL), health climate (HC), inner strength (IS), and perceived social support (PSS). Mental health outcomes assessed using the Core Symptom Index (CSI) were depression, anxiety, and somatic symptoms. Results: A total of 244 salespeople responded to the survey. CSI scores indicated that 18.4% (n = 45) and 10.2% (n = 25) of the respondents had symptoms of major depression and anxiety, respectively. ERI was positively correlated, while the IS and PSS were negatively correlated with major depression, anxiety, and somatic symptoms (p < .01). Health climate was negatively correlated with major depression (p < .05). Education background was associated with somatic symptoms (p < .05). ERI, IS, and gender were significant predictors of major depression, anxiety, and somatic symptoms (p < .05). Conclusion: The prevalence of depression and anxiety in China’s IVD international salespeople was considered low compared with prevalence in Chinese populations during COVID-19, but higher than those before the pandemic. Effort–reward imbalance, inner strength, and gender were significant factors in major depression, anxiety, and somatic symptoms among IVD international salespeople.