Isolation, whole genome sequencing and application of a broad-spectrum Salmonella phage.

Salmonella is considered as one of the most common zoonotic /foodborne pathogens in the world. The application of bacteriophages as novel antibacterial agents in food substrates has become an emerging strategy. Bacteriophages have the potential to control Salmonella contamination.We have isolated and characterized a broad-spectrum Salmonella phage, SP154, which can lyse 9 serotypes, including S. Enteritidis, S. Typhimurium, S. Pullorum, S. Arizonae, S. Dublin, S. Cholerasuis, S. Chester, S. 1, 4, [5], 12: i: -, and S. Derby, accounting for 81.9% of 144 isolates. SP154 showed a short latent period (40 min) and a high burst size (with the first rapid burst size at 107 PFUs/cell and the second rapid burst size at approximately 40 PFUs/cell). Furthermore, SP154 activity has higher survival rates across various environmental conditions, including pH 4.0-12.0 and temperatures ranging from 4 to 50 °C for 60 min, making it suitable for diverse food processing and storage applications. Significant reductions in live Salmonella were observed in different foods matrices such as milk and chicken meat, with a decrease of up to 1.9 log10 CFU/mL in milk contamination and a 1 log10 CFU/mL reduction in chicken meat. Whole genome sequencing analysis revealed that SP154 belongs to the genus Ithacavirus, subfamily Humphriesvirinae, within the family Schitoviridae. Phylogenetic analysis based on the terminase large subunit supported this classification, although an alternate tree using the tail spike protein gene suggested affiliation with the genus Kuttervirus, underscoring the limitations of relying on a single gene for phylogenetic inference. Importantly, no virulence or antibiotic resistance genes were detected in SP154. Our research highlights the potential of using SP154 for biocontrol of Salmonella in the food industry.

A potent endophytic fungus Purpureocillium lilacinum YZ1 protects against Fusarium infection in field-grown wheat.

Fusarium diseases pose a severe global threat to major cereal crops, particularly wheat. Existing biocontrol strains against Fusarium diseases are believed to primarily rely on antagonistic mechanisms, but not widely used under field conditions. Here, we report an endophytic fungus, Purpureocillium lilacinum YZ1, that shows promise in combating wheat Fusarium diseases. Under glasshouse conditions, YZ1 inoculation increased the survival rate of Fusarium graminearum (Fg)-infected wheat seedlings from 0% to > 60% at the seedling stage, and reduced spikelet infections by 70.8% during anthesis. In field trials, the application of YZ1 resulted in an impressive 89.0% reduction in Fg-susceptible spikelets. While a slight antagonistic effect of YZ1 against Fg was observed on plates, the induction of wheat systemic resistance by YZ1, which is distantly effective, non-specific, and long-lasting, appeared to be a key contributor to YZ1's biocontrol capabilities. Utilizing three imaging methods, we confirmed YZ1 as a potent endophyte capable of rapid colonization of wheat roots, and systematically spreading to the stem and leaves. Integrating dual RNA-Seq, photosynthesis measurements and cell wall visualization supported the link between YZ1's growth-promoting abilities and the activation of wheat systemic resistance. In conclusion, endophytes such as YZ1, which exhibits non-antagonistic mechanisms, hold significant potential for industrial-scale biocontrol applications.

Identification of the Ilex macrocarpa anthracnose pathogen and the antifungal potential of the cell-free supernatant of Bacillus velezensis against Colletotrichum fioriniae.

Introduction: Anthracnose is a significant fungal disease that affects tree growth and development, with Colletotrichum spp. exhibiting host non-specificity and targeting various organs, making disease control challenging. Methods: This study aimed to identify the pathogenic species causing anthracnose in Ilex macrocarpa in Nanchong, Sichuan Province, and screen effective fungicides, particularly biological ones. The pathogen was identified as Colletotrichum fioriniae through morphological observation, pathogenicity assays, and molecular biological methods. Three biological and five chemical fungicides were evaluated for their effects on the mycelial growth and spore germination rate of the pathogen. Results: The results indicated that prochloraz was the most effective chemical fungicide, while the cell-free supernatant (CFS) of Bacillus velezensis had the most significant inhibitory effect among the biological fungicides. Transcriptome analysis revealed that the CFS of B. velezensis significantly reduced the expression of genes associated with ribosomes, genetic information processing, membrane lipid metabolism, and sphingolipid biosynthesis in C. fioriniae. Additionally, the glutathione pathway's expression of various genes, including key genes such as GST, GFA, Grx, TRR, and POD, was induced. Furthermore, the expression of 17 MFS transporters and 9 ABC transporters was increased. Autophagy-related ATGs were also affected by the B. velezensis CFS. Discussion: These findings suggest that the B. velezensis CFS may inhibit C. fioriniae through interference with ribosomes, genetic information processing, cell membrane metabolism, and energy metabolism. These results provide potential target genes for the B. velezensis CFS and insights into the antifungal mechanism by which B. velezensis inhibits C. fioriniae.

Draft genome sequence of bacterium Bacillus proteolyticus strain IMGN4 from soil.

Here, we present the draft genome of Bacillus proteolyticus IMGN4, the gram-positive, soil-dwelling bacterium discovered in mountain Maemi, Republic of Korea in May 2019. The assembly resulted in 7 contigs, comprising a total of 6,063,502 base pairs and have 6,115 coding sequences.

Unraveling the genomic secrets of Tritonibacter mobilis AK171: a plant growth-promoting bacterium isolated from Avicennia marina.

The scarcity of freshwater resources resulting in a significant yield loss presents a pressing challenge in agriculture. To address this issue, utilizing abundantly available saline water could offer a smart solution. In this study, we demonstrate that the genome sequence rhizosphere bacterium Tritonibacter mobilis AK171, a halophilic marine bacterium recognized for its ability to thrive in saline and waterlogged environments, isolated from mangroves, has the remarkable ability to enable plant growth using saline irrigation. AK171 is characterized as rod-shaped cells, displays agile movement in free-living conditions, and adopts a rosette arrangement in static media. Moreover, The qualitative evaluation of PGP traits showed that AK171 could produce siderophores and IAA but could not solubilize phosphate nor produce hydrolytic enzymes it exhibits a remarkable tolerance to high temperatures and salinity. In this study, we conducted a comprehensive genome sequence analysis of T. mobilis AK171 to unravel the genetic mechanisms underlying its plant growth-promoting abilities in such challenging conditions. Our analysis revealed diverse genes and pathways involved in the bacterium's adaptation to salinity and waterlogging stress. Notably, T. mobilis AK171 exhibited a high level of tolerance to salinity and waterlogging through the activation of stress-responsive genes and the production of specific enzymes and metabolites. Additionally, we identified genes associated with biofilm formation, indicating its potential role in establishing symbiotic relationships with host plants. Furthermore, our analysis unveiled the presence of genes responsible for synthesizing antimicrobial compounds, including tropodithietic acid (TDA), which can effectively control phytopathogens. This genomic insight into T. mobilis AK171 provides valuable information for understanding the molecular basis of plant-microbial interactions in saline and waterlogged environments. It offers potential applications for sustainable agriculture in challenging conditions.

Physiological and genomic insights into a psychrotrophic drought-tolerant bacterial consortium for crop improvement in cold, semiarid regions.

The agricultural land in the Indian Himalayan region (IHR) is susceptible to various spells of snowfall, which can cause nutrient leaching, low temperatures, and drought conditions. The current study, therefore, sought an indigenous psychrotrophic plant growth-promoting (PGP) bacterial inoculant with the potential to alleviate crop productivity under cold and drought stress. Psychrotrophic bacteria preisolated from the night-soil compost of the Lahaul Valley of northwestern Himalaya were screened for phosphate (P) and potash (K) solubilization, nitrogen fixation, indole acetic acid (IAA) production, siderophore and HCN production) in addition to their tolerance to drought conditions for consortia development. Furthermore, the effects of the selected consortium on the growth and development of wheat (Triticum aestivum L.) and maize (Zea mays L.) were assessed in pot experiments under cold semiarid conditions (50 % field capacity). Among 57 bacteria with P and K solubilization, nitrogen fixation, IAA production, siderophore and HCN production, Pseudomonas protegens LPH60, Pseudomonas atacamensis LSH24, Psychrobacter faecalis LUR13, Serratia proteamaculans LUR44, Pseudomonas mucidolens LUR70, and Glutamicibacter bergerei LUR77 exhibited tolerance to drought stress (-0.73 MPa). The colonization of wheat and maize seeds with these drought-tolerant PGP strains resulted in a germination index >150, indicating no phytotoxicity under drought stress. Remarkably, a particular strain, Pseudomonas sp. LPH60 demonstrated antagonistic activity against three phytopathogens Ustilago maydis, Fusarium oxysporum, and Fusarium graminearum. Treatment with the consortium significantly increased the foliage (100 % and 160 %) and root (200 % and 133 %) biomasses of the wheat and maize plants, respectively. Furthermore, whole-genome sequence comparisons of LPH60 and LUR13 with closely related strains revealed genes associated with plant nutrient uptake, phytohormone synthesis, siderophore production, hydrogen cyanide (HCN) synthesis, volatile organic compound production, trehalose and glycine betaine transport, cold shock response, superoxide dismutase activity, and gene clusters for nonribosomal peptide synthases and polyketide synthetases. With their PGP qualities, biocontrol activity, and ability to withstand environmental challenges, the developed consortium represents a promising cold- and drought-active PGP bioinoculant for cereal crops grown in cold semiarid regions.

Phenotypic characterization and genomic analysis of a Salmonella phage L223 for biocontrol of Salmonella spp. in poultry.

The escalating incidence of foodborne salmonellosis poses a significant global threat to food safety and public health. As antibiotic resistance in Salmonella continues to rise, there is growing interest in bacteriophages as potential alternatives. In this study, we isolated, characterized, and evaluated the biocontrol efficacy of lytic phage L223 in chicken meat. Phage L223 demonstrated robust stability across a broad range of temperatures (20-70 °C) and pH levels (2-11) and exhibited a restricted host range targeting Salmonella spp., notably Salmonella Typhimurium and Salmonella Enteritidis. Characterization of L223 revealed a short latent period of 30 min and a substantial burst size of 515 PFU/cell. Genomic analysis classified L223 within the Caudoviricetes class, Guernseyvirinae subfamily and Jerseyvirus genus, with a dsDNA genome size of 44,321 bp and 47.9% GC content, featuring 72 coding sequences devoid of antimicrobial resistance, virulence factors, toxins, and tRNA genes. Application of L223 significantly (p < 0.005) reduced Salmonella Typhimurium ATCC 14,028 counts by 1.24, 2.17, and 1.55 log CFU/piece after 2, 4, and 6 h of incubation, respectively, in experimentally contaminated chicken breast samples. These findings highlight the potential of Salmonella phage L223 as a promising biocontrol agent for mitigating Salmonella contamination in food products, emphasizing its relevance for enhancing food safety protocols.

Isolation and characterization of native antagonistic rhizobacteria against Fusarium wilt of chilli to promote plant growth.

In the eastern coastal regions of Odisha, wilt caused by Fusarium oxysporum f. sp.capsici is an extremely damaging disease in chilli. This disease is very difficult to manage with chemical fungicides since it is soil-borne in nature. The natural rhizosphere soil of the chilli plant was used to isolate and test bacterial antagonists for their effectiveness and ability to promote plant growth. Out of the fifty-five isolates isolated from the rhizosphere of healthy chilli plants, five isolates, namely Iso 01, Iso 17, Iso 23, Iso 24, and Iso 32, showed their highly antagonistic activity against F. oxysporum f. sp. capsici under in vitro. In a dual culture, Iso 32 (73.3%) and Iso 24 (71.5%) caused the highest level of pathogen inhibition. In greenhouse trials, artificially inoculated chilli plants treated with Iso 32 (8.8%) and Iso 24 (10.2%) had decreased percent disease incidence (PDI), with percent disease reduction over control of 85.6% and 83.3%, respectively. Iso 32 and Iso 24 treated chilli seeds have shown higher seed vigor index of 973.7 and 948.8, respectively, as compared to untreated control 636.5. Furthermore, both the isolates significantly increased plant height as well as the fresh and dry weight of chilli plants under the rolled paper towel method. Morphological, biochemical, and molecular characterization identified Bacillus amyloliquefaciens (MH491049) as the key antagonist. This study demonstrates that rhizobacteria, specifically Iso 32 and Iso 24, can effectively protect chilli plants against Fusarium wilt while promoting overall plant development. These findings hold promise for sustainable and eco-friendly management of Fusarium wilt in chilli cultivation.

Actinobacteria as Promising Biocontrol Agents for In Vitro and In Planta Degradation and Detoxification of Zearalenone.

Zearalenone (ZEN) is a prevalent mycotoxin found in grains and grain-derived products, inducing adverse health effects in both animals and humans. The in-field application of microorganisms to degrade and detoxify ZEN is a promising strategy to enhance the safety of food and feed. In this study, we investigated the potential of three actinobacterial strains to degrade and detoxify ZEN in vitro and in planta on wheat ears. The residual ZEN concentration and toxicity in the samples were analysed with UHPLC-MS/MS and a bioluminescence BLYES assay, respectively. Streptomyces rimosus subsp. rimosus LMG19352 could completely degrade and detoxify 5 mg/L ZEN in LB broth within 24 h, along with significant reductions in ZEN concentration both in a minimal medium (MM) and on wheat ears. Additionally, it was the only strain that showed a significant colonisation of these ears. Rhodococcus sp. R25614 exhibited partial but significant degradation in LB broth and MM, whereas Streptomyces sp. LMG16995 degraded and detoxified ZEN in LB broth after 72 h by 39% and 33%, respectively. Although all three actinobacterial strains demonstrated the metabolic capability to degrade and detoxify ZEN in vitro, only S. rimosus subsp. rimosus LMG19352 showed promising potential to mitigate ZEN in planta. This distinction underscores the importance of incorporating in planta screening assays for assessing the potential of mycotoxin-biotransforming microorganisms as biocontrol agents.

Biocontrol of Occurrence Ochratoxin A in Wine: A Review.

Viticulture has been an important economic sector for centuries. In recent decades, global wine production has fluctuated between 250 and almost 300 million hectoliters, and in 2022, the value of wine exports reached EUR 37.6 billion. Climate change and the associated higher temperatures could favor the occurrence of ochratoxin A (OTA) in wine. OTA is a mycotoxin produced by some species of the genera Aspergillus and Penicillium and has nephrotoxic, immunotoxic, teratogenic, hepatotoxic, and carcinogenic effects on animals and humans. The presence of this toxin in wine is related to the type of wine-red wines are more frequently contaminated with OTA-and the geographical location of the vineyard. In Europe, the lower the latitude, the greater the risk of OTA contamination in wine. However, climate change could increase the risk of OTA contamination in wine in other regions. Due to their toxic effects, the development of effective and environmentally friendly methods to prevent, decontaminate, and degrade OTA is essential. This review summarises the available research on biological aspects of OTA prevention, removal, and degradation.

Biological Control of Tomato Bacterial Leaf Spots and Its Impact on Some Antioxidant Enzymes, Phenolic Compounds, and Pigment Content.

Tomato bacterial spots, caused by Xanthomonas campestris pv. vesicatoria (Xcv1) and X. euvesicatoria (Xe2), as well as bacterial specks, caused by two strains of Pseudomonas syringae pv. tomato (Pst1 and Pst2), represent significant threats to tomato production in the El-Sharkia governorate, often resulting in substantial yield losses. The objective of this study was to evaluate the efficacy of various biocontrol culture filtrates, including bacteria and fungi agents, in managing the occurrence and severity of these diseases, while also monitoring physiological changes in tomato leaves, including antioxidant enzymes, phenolics, and pigment content. The culture filtrates from examined Trichoderma species (T. viride, T. harzianum, and T. album), as well as the tested bacteria (Bacillus subtilis, Pseudomonas fluorescens, and Serratia marcescens) at concentrations of 25%, 50%, and 100%, significantly inhibited the proliferation of pathogenic bacteria In vitro. For the In vivo experiments, we used specific doses of 5 mL of spore suspension per plant for the fungal bioagents at a concentration of 2.5 × 107 spores/mL. The bacterial bioagents were applied as a 10 mL suspension per plant at a concentration of 1 × 108 CFU/mL. Spraying the culture filtrates of the tested bioagents two days before infection In vivo significantly reduced disease incidence and severity. Trichoderma viride exhibited the highest efficacy among the fungal bioagents, followed by T. harzianum and T. album. Meanwhile, the culture filtrate of B. subtilis emerged as the most potent among the bacterial bioagents, followed by P. fluorescens. Furthermore, applying these culture filtrates resulted in elevated levels of chitinase, peroxidase, and polyphenol oxidase activity. This effect extended to increased phenol contents, as well as chlorophyll a, chlorophyll b, and carotenoids in sprayed tomato plants compared to the control treatment. Overall, these findings underscore the potential of these biocontrol strategies to effectively mitigate disease incidence and severity while enhancing plant defense mechanisms and physiological parameters, thus offering promising avenues for sustainable disease management in tomato production.

Genome Analysis of Pseudomonas viciae G166 Conferring Antifungal Activity in Grapevine.

Grapevine (Vitis vinifera) is one of the major economic fruit crops but suffers many diseases, causing damage to the quality of grapes. Strain G166 was isolated from the rhizosphere of grapevine and was found to exhibited broad-spectrum antagonistic activities against fungal pathogens on grapes in vitro, such as Coniella diplodiella, Botrytis cinerea, and Colletotrichum gloeosporioides. Whole-genome sequencing revealed that G166 contained a 6,613,582 bp circular chromosome with 5749 predicted coding DNA sequences and an average GC content of 60.57%. TYGS analysis revealed that G166 belongs to Pseudomonas viciae. Phenotype analysis indicated that P. viciae G166 remarkably reduced the severity of grape white rot disease in the grapevine. After inoculation with C. diplodiella, more H2O2 and MDA accumulated in the leaves and resulted in decreases in the Pn and chlorophyll content. Conversely, G166-treated grapevine displayed less oxidative damage with lower H2O2 levels and MDA contents under the pathogen treatments. Subsequently, G166-treated grapevine could sustain a normal Pn and chlorophyll content. Moreover, the application of P. viciae G166 inhibited the growth of mycelia on detached leaves and berries, while more disease symptoms occurred in non-bacterized leaves and berries. Therefore, P. viciae G166 served as a powerful bioagent against grape white rot disease. Using antiSMASH prediction and genome comparisons, a relationship between non-ribosomal peptide synthase clusters and antifungal activity was found in the genome of P. viciae G166. Taken together, P. viciae G166 shows promising antifungal potential to improve fruit quality and yield in ecological agriculture.

Natural Prevalence, Molecular Characteristics, and Biological Activity of Metarhizium rileyi (Farlow) Isolated from Spodoptera frugiperda (J. E. Smith) Larvae in Mexico.

Entomopathogenic fungi have been considered potential biological control agents against the fall armyworm Spodoptera frugiperda (J. E. Smith), the world's most important pest of maize. In this study, we evaluated the natural infection, molecular characteristics, and biological activity of Metarhizium rileyi (Farlow) isolated from S. frugiperda larvae of this insect, collected from maize crops in five Mexican locations. Natural infection ranged from 23% to 90% across all locations analyzed. Twenty-four isolates were evaluated on S. frugiperda second instars at a concentration of 1.0 × 108 conidia/mL, causing 70% to 98.7% mortality and 60.5% to 98.7% sporulation. Isolates T9-21, Z30-21, PP48-21, and L8-22 were selected to determine their phylogenetic relationships by ß-tubulin gene analysis and to compare median lethal concentration (CL50), median lethal time (LT50), and larval survival. These isolates were grouped into three clades. The T9-21, PP48-21, and J10-22 isolates were closely related (clade A), but phylogenetically distant from Z30-21 (clade B) and L8-22 (clade C) isolates. These genetic differences were not always reflected in their pathogenicity characteristics since no differences were observed among the LC50 values. Furthermore, isolates T9-21, J10-22, and L8-22 were the fastest to kill S. frugiperda larvae, causing lower survival rates. We conclude that native M. rileyi isolates represent an important alternative for the biocontrol of S. frugiperda.

Complete genome sequence of the Exiguobacterium bacteriophage.

We purified a lytic bacteriophage from soil collected in Guasave, Sinaloa: phiExGM16. This bacteriophage was isolated using the host, Exiguobacterium acetilycum. Its 17.6 kb genome contains 33 putative genes and shows a cover of 64% with 76.37% of nucleotide identity to Microbacterium phage Noelani.

Molecular and aflatoxigenicity analyses of Aspergillus flavus isolates indigenous to grain corn in Malaysia; potentials for biological control.

AIMS: The present work aimed to distinguish the indigenous Aspergillus flavus isolates obtained from the first (pioneer) grain corn farms in Terengganu, Malaysia, into aflatoxigenic and non-aflatoxigenic by molecular and aflatoxigenicity analyses, and determine the antagonistic capability of the non-aflatoxigenic isolates against aflatoxigenic counterparts and their aflatoxin production in vitro. METHODS AND RESULTS: Seven A. flavus isolates previously obtained from the farms were characterized molecularly and chemically. All isolates were examined for the presence of seven aflatoxin biosynthesis genes, and their aflatoxigenicity was confirmed using high performance liquid chromatography with fluorescence detector. Phylogenetic relationships of all isolates were tested using ITS and ß-tubulin genes. Of the seven isolates, two were non-aflatoxigenic, while the remaining were aflatoxigenic based on the presence of all aflatoxin biosynthesis genes tested and the productions of aflatoxins B1 and B2. All isolates were also confirmed as A. flavus following phylogenetic analysis. The indigenous non-aflatoxigenic isolates were further examined for their antagonistic potential against aflatoxigenic isolates on 3% grain corn agar. Both non-aflatoxigenic isolates significantly reduced AFB1 production of the aflatoxigenic isolates. CONCLUSION: The indigenous non-aflatoxigenic A. flavus strains identified in the present work were effective in controlling the aflatoxin production by the aflatoxigenic A. flavus isolates in vitro and can be utilized for in situ testing.

Characterization of the novel phage vB_BceP_LY3 and its potential role in controlling Bacillus cereus in milk and rice.

Bacillus cereus is a foodborne pathogen that induces vomiting and diarrhea in affected individuals. It exhibits resistance to traditional sterilization methods and has a high contamination rate in dairy products and rice. Therefore, the development of a new food safety controlling strategy is necessary. In this research, we isolated and identified a novel phage named vB_BceP_LY3, which belongs to a new genus of the subfamily Northropvirinae. This phage demonstrates a short latency period and remains stable over a wide range of temperatures (4-60 °C) and pH levels (4-11). The 28,124 bp genome of LY3 does not contain any antibiotic-resistance genes or virulence factors. With regards to its antibacterial properties, LY3 not only effectively inhibits the growth of B. cereus in TSB (tryptic soy broth), but also demonstrates significant inhibitory effects in various food matrices. Specifically, LY3 treatment at 4 °C with a high MOI (MOI = 10,000) can maintain B. cereus levels below the detection limit for up to 24 h in milk. LY3 represents a safe and promising biocontrol agent against B. cereus, possessing long-term antibacterial capabilities and stability.

Identification and mechanism characterization of Streptomyces griseoaurantiacus XQ-29 with biocontrol ability against pepper southern blight caused by Sclerotium rolfsii.

Pepper southern blight, caused by Sclerotium rolfsii, is a devastating soil-borne disease resulting in significant loss to pepper, Capsicum annuum L. production. Here, we isolated an antagonistic bacterial strain XQ-29 with antifungal activity against S. rolfsii from rhizospheric soil of pepper. Combining the morphological and biochemical characteristics with the 16S rDNA sequencing, XQ-29 was identified as Streptomyces griseoaurantiacus. It exhibited an inhibition of 96.83% against S. rolfsii and displayed significant inhibitory effects on Botrytis cinerea, Phytophthora capsica and Rhizoctonia solani. Furthermore, XQ-29 significantly reduced the pepper southern blight by 100% and 70.42% during seedling and growth stages, respectively. The antifungal mechanism involved altering the mycelial morphology, disrupting cell wall and membrane integrity, accompanied by accumulation of reactive oxygen species and lipid peroxidation in S. rolfsii mycelia. Furthermore, XQ-29 promoted growth and stimulated resistance of pepper plants by increasing defense-related enzyme activities and upregulating defense-related genes. Correspondingly, XQ-29 harbors numerous functional biosynthesis gene clusters in its genome, including those for siderophores and melanin production. The metabolic constituents present in the ethyl acetate extracts, which exhibited an EC50 value of 85.48 ± 1.62 µg/mL, were identified using LC-MS. Overall, XQ-29 demonstrates significant potential as a biocontrol agent against southern blight disease.

A review of applications and limitations of using aquatic macroinvertebrate predators for biocontrol of the African malaria mosquito, Anopheles gambiae sensu lato.

Macroinvertebrate predators such as backswimmers (Heteroptera: Notonectidae), dragonflies (Odonata: Aeshnidae), and predatory diving beetles (Coleoptera: Dytiscidae) naturally inhabit aquatic ecosystems. Some aquatic ecosystems inhabited by these macroinvertebrate predator taxa equally form malaria vector larval habitats. The presence of these predators in malaria vector larval habitats can negatively impact on development, adult body size, fecundity, and longevity of the malaria vectors, which form important determinants of their fitness and future vectorial capacity. These potential negative impacts caused by aquatic macroinvertebrate predators on malaria vectors warrant their consideration as biocontrol agents in an integrated program to combat malaria. However, the use of these macroinvertebrate predators in malaria biocontrol is currently constrained by technical bottlenecks linked to their generalist predatory tendencies and often long life cycles, demanding complex rearing systems. We reviewed the literature on the use of aquatic macroinvertebrate predators for biocontrol of malaria vectors from the An. gambiae s.l. complex. The available information from laboratory and semi-field studies has shown that aquatic macroinvertebrates have the potential to consume large numbers of mosquito larvae and could thus offer an additional approaches in integrated malaria vector management strategies. The growing number of semi-field structures available in East and West Africa provides an opportunity to conduct ecological experimental studies to reconsider the potential of using aquatic macroinvertebrate predators as a biocontrol tool. To achieve a more sustainable approach to controlling malaria vector populations, additional, non-chemical interventions could provide a more sustainable approach, in comparison with the failing chemical control tools, and should be urgently considered for integration with the current mosquito vector control campaigns.

Cladosporium psychrotolerans strain T01 enhances plant biomass and also exhibits antifungal activity against pathogens.

An increasing number of microorganisms are being identified to enhance plant growth and inhibit phytopathogens. Some Cladosporium species form beneficial associations with plants, either as endophytes or by colonizing the rhizosphere. Herein, we evaluated the influence of the Cladosporium psychrotolerans (T01 strain) fungus on the in vitro growth of Arabidopsis thaliana plantlets through direct and split interactions. After 9 days post-inoculation with C. psychrotolerans, Arabidopsis plantlets exhibited a notable increase in fresh weight and lateral roots, particularly in split interactions. Chlorophyll content increased in both plant-fungus interaction conditions, whereas the primary root was inhibited during direct interaction. We observed an increase in the GUS signal from the Arabidopsis auxin-inducible DR5:uidA marker in lateral root tips in both contact and split fungal interactions, and primary root tips in a split interaction. Arabidopsis and tomato plants cultivated in soil pots and inoculated with C. psychrotolerans (T01 strain) showed a positive effect on biomass production. GC/MS analysis detected that the T01 strain emitted volatile organic compounds (VOCs), predominantly alcohols and aldehydes. These VOCs displayed potent inhibitory effects, with a 60% inhibition against Botrytis cinerea and a 50% inhibition against C. gloeosporioides. Our study demonstrates that C. psychrotolerans T01 has the potential to enhance biomass production and inhibit pathogens, making it a promising candidate for green technology applications.

Antagonistic potential of endophytic fungal isolates of tomato (Solanum lycopersicum L.) fruits against post-harvest disease-causing pathogens of tomatoes: An in vitro investigation.

Post-harvest decay of fresh agricultural produce is a major threat to food security globally. Synthetic fungicides, commonly used in practice for managing the post-harvest losses, have negative impacts on consumers' health. Studies have reported the effectiveness of fungal isolates from plants as biocontrol agents of post-harvest diseases, although this is still poorly established in tomatoes (Solanum lycopersicum L. cv. Jasmine). In this study, 800 endophytic fungi were isolated from mature green and ripe untreated and fungicide-treated tomato fruits grown in open soil and hydroponics systems. Of these, five isolates (Aureobasidium pullulans SUG4.1, Coprinellus micaceus SUG4.3, Epicoccum nigrum SGT8.6, Fusarium oxysporum HTR8.4, Preussia africana SUG3.1) showed antagonistic properties against selected post-harvest pathogens of tomatoes (Alternaria alternata, Fusarium solani, Fusarium oxysporum, Geotrichum candidum, Rhizopus stolonifera, Rhizoctonia solani), with Lactiplantibacillus plantarum as a positive control. P. africana SUG3.1 and C. micaceus SUG4.3 significantly inhibited growth of all the pathogens, with antagonistic capabilities comparable to that exhibited by L. plantarum. Furthermore, the isolates produced an array of enzymes, including among others, amylase, cellulose and protease; and were able to utilize several carbohydrates (glucose, lactose, maltose, mannitol, sucrose). In conclusion, P. africana SUG3.1 and C. micaceus SUG4.3 may complement L. plantarum as biocontrol agents against post-harvest pathogens of tomatoes.