The novel bacteriocin BacYB1 produced by Leuconostoc mesenteroides YB1: From recent analytical characterization to biocontrol Verticillium dahliae and Agrobacterium tumefaciens.

Biocontrol of phytopathogens involving the use of bioactive compounds produced by lactic acid bacteria (LAB), is a promising approach to manage many diseases in agriculture. In this study, a lactic acid bacterium designated YB1 was isolated from fermented olives and selected for its antagonistic activity against Verticillium dahliae (V. dahliae) and Agrobacterium tumefaciens (A.

Bacillus methylotrophicus DCS1: Production of Different Lipopeptide Families, In Vitro Antifungal Activity and Suppression of Fusarium Wilt in Tomato Plants.

The present work aims to quantitatively and qualitatively monitor the production of lipopeptide mixtures by Bacillus methylotrophicus DCS1 strain in Landy medium and to investigate the antifungal activities of DCS1 strain and its produced lipopeptides. The in vitro activities were tested by the direct confrontation and agar well diffusion methods, while the in vivo study was carried out in order to test the efficiency of DCS1 bacterial suspension in the control of Fusarium wilt in tomato plants. Identification of lipopeptides by mass spectrometry (LC/MSD-TOF) showed that lipopeptide isoforms produced during the first 24 h and 48 h of fermentation are identical, belonging to bacillomycin D and fengycins A and B homologues with a difference in the yield of production.

SPB1 lipopeptide biosurfactant: antibacterial efficiency against the phytopathogenic bacteria and compared production in submerged and solid state fermentation systems.

SPB1 derived biosurfactants (BioS) proved its bio-control activity against using tomato plant. Almost 83% of disease symptoms triggered by were reduced. Aiming potential application, we studied lipopeptide cost-effective production in both fermentations systems, namely the submerged fermentation (SmF) and the solid-state fermentation (SSF) as well as the use of Aleppo pine waste and confectionery effluent as cheap substrates.

Exploring Bacterial and Fungal Biodiversity in Eight Mediterranean Olive Orchards ( L.) in Tunisia.

A wide array of bacteria and fungi are known for their association with pests that impact the health of the olive tree. The latter presents the most economically important cultivation in Tunisia. The microbial diversity associated with olive orchards in Tunisia remains unknown and undetermined.

Desirable traits for a good biocontrol agent against fire blight disease.

Aims: This study aimed to improve the screening strategy for the selection of biocontrol agents with high biocontrol efficacy against fire blight disease.

Methods And Results: A two-step screening procedure consisting of in-vitro laboratory tests and an ex-vivo test system using detached pear leaves was applied to 43 Bacillus strains originated from the rhizosphere and the aerial parts of apple and pear plants. The grouping of the studied strains and the tested traits based on the principal component analysis and the two-way hierarchical cluster analysis showed that siderophore production and biofilm formation are the most desirable traits in a Bacillus biocontrol agent to control fire blight disease and that rhizospheric originating strains are the most effective.

Identification of fungi in Tunisian olive orchards: characterization and biological control potential.

Background: Olive production is the main agricultural activity in Tunisia. The diversity of fungi was explored in two different olive groves located in two distant geographical zones in Sfax (Tunisia) with different management practices.

Results: Fungal isolation was made from soil and the major olive tree pests, namely the Olive fly, Bactrocera oleae Gmelin (Diptera: Tephritidae), and the Olive psyllid, Euphyllura olivina Costa (Homoptera: Psyllidae).

Physico-chemical and spectroscopic quality assessment of compost from date palm (Phoenix dactylifera L.) waste valorization.

Organic matter (OM) is a vital component for a healthy soil, its lack arise a major problem for farmers who need to use commercialized fertilizers with high costs. Considering circular economy approach and for increasing OM availability, water soaked date palm waste was co-composted with goat manure in aerated windrow to produce a soil organic amendment. The OM biodegradation was mainly controlled based on biological parameters and spectroscopic techniques.

Providencia entomophila sp. nov., a new bacterial species associated with major olive pests in Tunisia.

Bioprospection for potential microbial biocontrol agents associated with three major insect pests of economic relevance for olive cultivation in the Mediterranean area, namely the olive fly, Bactrocera oleae, the olive moth, Prays oleae, and the olive psyllid, Euphyllura olivina, led to the isolation of several strains of readily cultivable Gram-negative, rod-shaped bacteria from Tunisian olive orchards. Determination of 16S ribosomal RNA encoding sequences identified the bacteria as members of the taxonomic genus Providencia (Enterobacterales; Morganellaceae). A more detailed molecular taxonomic analysis based on a previously established set of protein-encoding marker genes together with DNA-DNA hybridization and metabolic profiling studies led to the conclusion that the new isolates should be organized in a new species within this genus.

L. Root Endophyte OEE1 Counteracts Oomycete and Fungal Harmful Pathogens and Harbours a Large Repertoire of Secreted and Volatile Metabolites and Beneficial Functional Genes.

Oomycete and fungal pathogens, mainly and species, are notorious causal agents of huge economic losses and environmental damages. For instance, , , and cause significant losses in nurseries and in forest ecosystems. Chemical treatments, while harmful to the environment and human health, have been proved to have little or no impact on these species.

Screening of the High-Rhizosphere Competent ' Culturable Endophyte Microbiota Allows the Recovery of Multifaceted and Versatile Biocontrol Agents.

Halophyte , an evergreen shrub inhabiting the Mediterranean region, has well-documented phytoremediation potential for metal removal from polluted sites. It is also considered to be a medicinal halophyte with potent activity against plant pathogens. Therefore, may be a suitable candidate for isolating endophytic microbiota members that provide plant growth promotion (PGP) and resistance to abiotic stresses.

Screening for Antagonistic Bacteria From Contrasting Niches Designated the Endophyte as Plant Warden Against .

Date palm ( L.) plantations in North Africa are nowadays threatened with the spread of the Bayoud disease caused by f. sp.

Economic production and biocontrol efficiency of lipopeptide biosurfactants from Bacillus mojavenis A21.

In the wake of an increased attention on the eco-friendly biopesticidal products and the rising market requirements for organic agents, lipopeptides compounds have been described as biological control agents which improve the overall health growth and development of plants. Nevertheless, their high production cost constitue the major flaw in their wide use to control plant diseases. The present article aims to formulate an economic media for lipopeptides production by Bacillus mojavensis A21 for application as natural fungicides for plant disease treatment.

MIP diversity from Trichoderma: Structural considerations and transcriptional modulation during mycoparasitic association with Fusarium solani olive trees.

Major intrinsic proteins (MIP) are characterized by a transmembrane pore-type architecture that facilitates transport across biomembranes of water and a variety of low molecular weight solutes. They are found in all parts of life, with remarkable protein diversity. Very little is known about MIP from fungi.

Multiple linear regression and artificial neural networks for delta-endotoxin and protease yields modelling of Bacillus thuringiensis.

The aim of the present work was to develop a model that supplies accurate predictions of the yields of delta-endotoxins and proteases produced by B. thuringiensis var. kurstaki HD-1.

Bayesian and Phylogenic Approaches for Studying Relationships among Table Olive Cultivars.

To enhance table olive tree authentication, relationship, and productivity, we consider the analysis of 18 worldwide table olive cultivars (Olea europaea L.) based on morphological, biological, and physicochemical markers analyzed by bioinformatic and biostatistic tools. Accordingly, we assess the relationships between the studied varieties, on the one hand, and the potential productivity-quantitative parameter links on the other hand.

Morphological and molecular characterization of Fusarium spp. associated with olive trees dieback in Tunisia.

Dieback and wilting symptoms caused by complex soilborne fungi are nowadays the most serious threatening disease affecting olive trees (Olea europaea) in Tunisia and presumably in many Mediterranean basin countries. Fusarium is one of the important phytopathogenic genera associated with dieback symptoms of olive trees. The objective of the present study was to confirm the pathogenicity of Fusarium spp.

The use of newly isolated Streptomyces strain TN258 as potential biocontrol agent of potato tubers leak caused by Pythium ultimum.

An actinomycete strain designated TN258, was isolated from Tunisian Sahara soil and selected for its antagonistic activity, especially against Pythium ultimum (P. ultimum) causing potato tubers leak. Based on the results of cultural characteristic of TN258 strain, the 16S rRNA gene nucleotide sequence (1433 bp, accession n° HE600071) and the phylogenetic analysis, we propose the assignment of our new isolate bacterium as Streptomyces TN258 strain.

Lipopeptides from a novel Bacillus methylotrophicus 39b strain suppress Agrobacterium crown gall tumours on tomato plants.

Background: This study aims to characterise the antibacterial activity of a novel Bacillus methylotrophicus strain named 39b against tumourigenic Agrobacterium tumefaciens C58 and B6 strains. It also aims to identify the compound that is responsible for its activity and to evaluate its efficiency to control crown gall disease in tomato plants.

Results: B.

Purification and identification of Bacillus subtilis SPB1 lipopeptide biosurfactant exhibiting antifungal activity against Rhizoctonia bataticola and Rhizoctonia solani.

This study reports the potential of a soil bacterium, Bacillus subtilis strain SPB1, to produce lipopeptide biosurfactants. Firstly, the crude lipopeptide mixture was tested for its inhibitory activity against phytopathogenic fungi. A minimal inhibitory concentration (MIC), an inhibitory concentration at 50% (IC50%), and an inhibitory concentration at 90% (IC90%) values were determined to be 0.

Ruta montana L. leaf essential oil and extracts: characterization of bioactive compounds and suppression of crown gall disease.

The aims of this study were to assess the antimicrobial efficacy of the leaf essential oil and the leaf extracts of R. montana against Botrytis cinerea, Fusarium oxysporum, Verticillium dahliae, Aspergillus oryzae and Fusarium solani. The oil (1.

Biocontrol of tomato plant diseases caused by Fusarium solani using a new isolated Aspergillus tubingensis CTM 507 glucose oxidase.

The present study focuses on the potential of glucose oxidase (GOD) as a promising biocontrol agent for fungal plant pathogens. In fact, a new GOD producing fungus was isolated and identified as an Aspergillus tubingensis. GOD (125 AU) has been found to inhibit Fusarium solani growth and spore production.

Antifungal efficiency of a lipopeptide biosurfactant derived from Bacillus subtilis SPB1 versus the phytopathogenic fungus, Fusarium solani.

Bacillus subtilis SPB1 lipopeptides were evaluated as a natural antifungal agent against Fusarium solani infestation. In vitro antifungal assay showed a minimal inhibitory concentration of about 3 mg/ml with a fungicidal mode of action. In fact, treatment of F.

Isolation and characterization of rhizosphere bacteria for the biocontrol of the damping-off disease of tomatoes in Tunisia.

Fluorescent Pseudomonas spp., isolated from tomato and pepper plants rhizosphere soil, was evaluated in vitro as a potential antagonist of fungal pathogens. Pseudomonas strains were tested against the causal agents of tomatoes damping-off (Sclerotinia sclerotiorum), root rot (Fusarium solani), and causal agents of stem canker and leaf blight (Alternaria alternata).