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The filtrate of the nematophagous fungus Duddingtonia flagrans produces silver nanoparticles (AgNPs) with nematicidal potential. However, there are currently no reports of its activity against Toxocara canis eggs. The aim of this study was to investigate the potential ovicidal activity of AgNPs–D. flagrans on T. canis eggs. T. canis eggs were obtained from the dissection of the uterus of adult female nematodes. After the biosynthesis of AgNPs, two experimental assays (A and B) were performed. In assay A, the ovicidal activity of AgNPs on eggs was evaluated after 15 and 30 days of interaction. In assay B, the inhibition (development) of the eggs was measured after 30 days of interaction. The results of assay A showed that the AgNPs destroyed an average of 47% of the eggs tested by the end of the experiment, causing significant structural damage. In assay B, an inhibition rate of 88% was observed at the end of 30 days. The results of the ovicidal activity of AgNP–D. flagrans were promising and indicate the potential for future studies on these biomolecules with ovicidal properties. [ABSTRACT FROM AUTHOR]

The filtrate of the nematophagous fungus Duddingtonia flagrans produces silver nanoparticles (AgNPs) with nematicidal potential. However, there are currently no reports of its activity against Toxocara canis eggs. The aim of this study was to investigate the potential ovicidal activity of AgNPs–D. flagrans on T. canis eggs. T. canis eggs were obtained from the dissection of the uterus of adult female nematodes. After the biosynthesis of AgNPs, two experimental assays (A and B) were performed. In assay A, the ovicidal activity of AgNPs on eggs was evaluated after 15 and 30 days of interaction. In assay B, the inhibition (development) of the eggs was measured after 30 days of interaction. The results of assay A showed that the AgNPs destroyed an average of 47% of the eggs tested by the end of the experiment, causing significant structural damage. In assay B, an inhibition rate of 88% was observed at the end of 30 days. The results of the ovicidal activity of AgNP–D. flagrans were promising and indicate the potential for future studies on these biomolecules with ovicidal properties.

The endoparasitic fungus Hirsutella rhossiliensis is an important biocontrol agent of cyst nematodes in nature. To determine the potential parasitism of the fungus on a non-natural host, the pinewood nematode (Bursaphelenchus xylophilus) living in pine trees and the endophytic ability of the fungus on plants, in this paper, we first constructed and utilized a green fluorescent protein (GFP)-tagged H. rhossiliensis HR02 transformant to observe the fungal infection process on B. xylophilus and its colonization on Arabidopsis roots. Then, we compared the fungal parasitism on three species of nematodes with different lifestyles, and we found that the fungal parasitism is correlated with nematode species and stages. The parasitic effect of H. rhossiliensis on adults of B. xylophilus is similar to that on second-stage juveniles (J2) of the root-knot nematode Meloidogyne incognita after 24 h of inoculation, although the virulence of the fungus to second-stage juveniles of M. incognita is stronger than that to those of B. xylophilus and Caenorhabditis elegans. Moreover, the endophytism of H. rhossiliensis was confirmed. By applying an appropriate concentration of H. rhossiliensis conidial suspension (5 × 106 spores/mL) in rhizosphere soil, it was found that the endophytic fungus can promote A. thaliana growth and reproduction, as well as improve host resistance against M. incognita. Our results provide a deeper understanding of the fungus H. rhossiliensis as a promising biocontrol agent against plant-parasitic nematodes. [ABSTRACT FROM AUTHOR]

Root-knot nematodes (Meloidogyne spp.) cause great losses in tomato crops. An environmentally friendly for its control is the use of predatory fungi such as Purporeocillum lilacinum, which reduces its population in the soil and mitigates yield losses. Therefore, the objective of the present study was to evaluate the biocontrol efficacy of the strains of the nematophagous fungus Purporeocillum lilacinum and liquid bioformulates on the eggs of the root-knot nematode Meloidogyne incognita, and the formation of galls on the tomato root. Two native strains of Purporeocillum lilacinum H2 and H3 combined with the bioformulated Extract of Beneficial Microorganisms (EPMB®) and the root exudate stimulator Exu-Root® were tested on Meloidogyne incognita eggs and tomato plants. The results obtained indicate that the Purporeocillum lilacinum H2 and H3 strains infected the Meloidogyne incognita eggs, interrupted the development of the embryos and caused their death, which significantly reduced the presence of galls in the root of the plants. In short, the maximum biological performance was presented with the treatments H2+Exu-Root® and H3+EPMB®, which had the lowest number of galls with 19.2 and 20.3 galls per plant respectively, compared to the control that presented 88 galls in the root and the treatments where the fungus was not applied (69-85 galls). Finally, it is concluded that the results demonstrate the potential of the Purporeocillum lilacinum H2 and H3 strains as biocontrol agents against the root-knot nematode Meloidogyne incognita, and that, in combination with EPMB® and Exu-Root®, the efficacy can be increased to reduce its population. [ABSTRACT FROM AUTHOR]

The objective of this study was to evaluate the effect of the combined application of biochars and the nematophagous fungus Pochonia chlamydosporia (Goddard) Zare and Gams on growth of tomato plants (Solanum lycopersicum L.) cv. 'Elbita' and their protection against Meloidogyne incognita (Kofoid and White) Chitwood. The biochars were produced from: rice husk (Oryza sativa L.), branches of leucaena (Leucaena leucocephala (Lam.) de Wit.) and marabou (Dichrostachys cinerea Wight et Am.), mango seeds (Mangifera indica L.), and coconut fiber (Cocos nucifera L.), using Kon-Tiki technology. The biochars and P. chlamydosporia strain IMI SD 187 (dose of 5x10³ chlamydospores.g-1 of substrate) were added to the substrate consisting of red ferralitic soil: cattle manure: biochar (2:1:1 v/v). The experiment was carried out in 60 cell trays, which were randomly distributed in biological isolators. Control treatments without the fungus were included. After 30 days, vegetative growth and colonization of the substrate and roots by P. chlamydosporia were evaluated. Subsequently, five plants from the rice husk biochar + P. chlamydosporia treatment were transplanted to pots containing one kg of sterile substrate (soil: cattle manure 1:1 v/v), inoculated with 500 juveniles of a pure population of M. incognita, and to control pots without nematodes and left to grow for 60 days. The vegetative growth and the nematode gall index were evaluated. The application of biochars and P. chlamydosporia did not affect rhizosphere colonization by the fungus and showed a positive effect on growth of tomato plants. The fungus with rice biochar achieved early protection against M. incognita. [ABSTRACT FROM AUTHOR]

The aim of the present study was to perform the histopathological and enzymatic evaluation of the intestines of Swiss mice infected with Strongyloides venezuelensis after oral administration of the fungus Duddingtonia flagrans (AC001). Twenty mice were used, all previously dewormed and kept in individual cages with granulated feed and drinking water provided ad libitum. After this period, the animals were randomly divided into four experimental groups: Group 1 (animals infected with 700 L3 of S. venezuelensis), Group 2 (animals infected with 700 L3 of S. venezuelensis + orally treated with 500 chlamydospores and 500 conidia of AC001), Group 3 (animals not infected with L3 from S. venezuelensis + orally treated with 500 chlamydospores and 500 conidia from AC001) and Group 4, control (uninfected and untreated animals with chlamydospores and AC001 conidia). After that, all animals were euthanized and necropsied. Intestinal tissue collections were intended for histopathology and enzymatic quantification of Eosinophilic Peroxidase (EPO) and Myeloperoxidase (MPO). At the end of the trial, the results showed that there was no change and/or destruction of the intestinal microvilli in the groups (G2 and G3) that received orally chlamydospores/conidia of AC001. Oral treatments with AC001 did not induce any significant increase in EPO and MPO levels in the experimental groups (G2 and G3), when compared to the control group G4 (p < 0.05). It was concluded that the fungus D. flagrans (AC001) did not cause changes in the intestinal microvilli, nor did it interfere in the levels of EOP and MPO. [ABSTRACT FROM AUTHOR]

Recently, the production process of a nanoparticle with nematicidal activity from a nematophagous fungus was developed. Thus, a new strategy to control parasites has been discovered. The aim of the present study was to evaluate the in vitro activity of silver nanoparticles (AgNP's) biosynthesized from Duddingtonia flagrans filtrate on the control of strongylid larvae of ruminants. This is the first report of a nematicidal activity of AgNP's – D. flagrans on bovine strongylids, which can be an important biotechnological tool for the use of nanoparticles produced from D. flagrans. [ABSTRACT FROM AUTHOR]

Recently, the production process of a nanoparticle with nematicidal activity from a nematophagous fungus was developed. Thus, a new strategy to control parasites has been discovered. The aim of the present study was to evaluate the in vitro activity of silver nanoparticles (AgNP's) biosynthesized from Duddingtonia flagrans filtrate on the control of strongylid larvae of ruminants. This is the first report of a nematicidal activity of AgNP's – D. flagrans on bovine strongylids, which can be an important biotechnological tool for the use of nanoparticles produced from D. flagrans. [ABSTRACT FROM AUTHOR]

Pine wilt disease is a devastating forest disease worldwide caused by the pinewood nematode (PWN; Bursaphelenchus xylophilus). Esteya vermicola is widely recognized as a promising bio‐control agent effective against PWN. During a survey of associated microorganisms of Pinus yunnanensis in Southwest China, a novel isolate of E. vermicola was obtained. This isolate produced two types of conidia. One type of conidia was hyaline, unicellular, bacilloid, and non‐adhesive. The second type of conidia is solitary, hyaline, unicellular asymmetric elliptic or lunate, concave inward, ending slightly apiculate, adhesive on the concave surface, and contained an ovoid endospore‐like structure. Only the lunate conidia showed infection activity against PWN. This novel isolate produced a high proportion of infective lunate conidia and exhibited high adhesion and infection activity against PWN by adhering to the nematode within 48 h and killing 74.5% of the tested PWN individuals within 4 days. Given that the isolate was obtained from P. yunnanensis, it may be well adapted to the endogenous environment of pine trees. The isolate shows potential as a bio‐control agent against a plant‐parasitic nematode in the field. [ABSTRACT FROM AUTHOR]

In Algeria, vegetable crops occupy an important cultivated area which accounts for 70% of the total arable land. The Sahel and coastal areas are particularly occupied by plasticulture due to favorable pedoclimatic conditions, which also allows the outbreak of various diseases and pests. Among the latter, the root-knot nematodes of the genus Meloidogyne are considered as one of the most important phytosanitary problems both in open fields and greenhouses. Biological control is a realistic alternative to replace or at least minimize the use of chemicals. The study of microflora is essential for targeting new biological agents for pest control. Two study stations belonging to Algiers are selected: Staoueli and Bordj el Kiffan. Between 2017 and 2018, soil samples were taken at random from a depth of 0 to 10 cm inside the greenhouses (treated soils) and outside the greenhouses (no treatment). The results obtained revealed a diversity of species of nematophagous fungi belonging to 8 genera, Arthrobotrys, Dactylaria, Dactylella, Myzocytium, Harposporium, Rhopalomyces, Stylopage and Triposporina. The most frequent species is Arthorobotrys musiformis with a rate of 77.5% in untreated Bordj-el-kiffan soils and 57.5% in treated soils, Staouali has a percentage of 55% and 57.5% in treated and untreated soils respectively. This study give new insights regarding the availability of endemic nematophagous fungi vegetables fields. Parasitism assessment indicated that 8 nematophagous fungi were efficient to suppress M. incognita and M. javanica by 70% and 50%, respectively. This indicate their potential as biocontrol agents against plant parasitic nematodes. [ABSTRACT FROM AUTHOR]

The complete mitochondrial genome of Purpureocillium lavendulum was characterized in this study. This mitogenome is a closed circular molecule of 23,567 bp in length with a GC content of 28.46%, including 15 protein-coding genes, 25 transfer RNA genes, 2 ribosomal RNA genes. Phylogenetic analyses based on sequences at the 14 concatenated mitochondrial protein-coding genes showed that P. lavendulum was closely related to Hirsutella minnesotensis.

Duddingtonia flagrans is a biological alternative to the use of anthelmintic drugs in ruminants. This fungus must be ingested by the animal, pass through the cavities of the digestive tract and reach the feces where it develops traps that capture the nematodes. The severe conditions encountered in this process negatively affect the fungus, which is reflected in the low recovery rates compared to the amount administered. The aim of this study was to evaluate independently the in vitro effect of typical physical and chemical conditions of the gastrointestinal cavities of ruminants on the concentration, viability, and the in vitro nematode predatory ability of the chlamydospores of D. flagrans. The factors evaluated individually were pH (2, 6, and 8), temperature (28 ± 2°C and 39 ± 2°C), exposure to artificial saliva, and milling. The results showed that the concentration and viability of D. flagrans were not affected by the action of pH, temperature, milling, or exposure to artificial saliva. Regarding the in vitro nematode predatory ability, a reduction was observed after the milling process and the exposure for 24 h at different pH. [ABSTRACT FROM AUTHOR]

The egg-pathogenic fungus Purpureocillium lilacinum parasitizes on nematode eggs, and thus, it is used as a good biocontrol agent against plant root-knot nematodes. However, little is known about the transcriptional response of P. lilacinum while infecting nematode eggs. This study presents the whole transcriptome sequencing of P. lilacinum and transcriptome-wide gene expression analysis of P. lilacinum upon infecting the eggs of Meloidogyne incognita compared to non-infecting controls. A transcriptomic library of P. lilacinum was used as reference gene set and six transcriptomic libraries of the non-infecting control and P. lilacinum infecting M. incognita eggs were constructed, respectively, comprising three biological replicates of each. A total of 1,011 differently expressed genes (DEGs) were identified in the infecting samples, including 553 up-regulated and 458 down-regulated genes compared to the non-infecting control samples. Furthermore, functional enrichment analysis exhibited that these DEGs were primarily involved in oxidative phosphorylation, oxidoreductase activity, and metabolic processes. Fifteen DEGs were randomly selected to verify the RNA sequencing results through quantitative real-time polymerase chain reaction (qPCR). The study focused on P. lilacinum genes that were strongly expressed upon infecting M. incognita eggs. These DEGs were primarily involved in detoxification, parasitic behavior, and nutritional utilization. This study contributes significantly to the understanding of the molecular mechanisms underlying the parasitic action of P. lilacinum on nematode eggs and provides a valuable genetic resource for further research on parasitic behavior of P. lilacinum. Notably, this study examined the transcriptomics of P. lilacinum infecting M. incognita eggs at only one time point. Since there were fungi at different stages of the infection process at that time point, the transcriptional profiles are not precisely examining one specific stage in this process.

The egg-pathogenic fungus Purpureocillium lilacinum parasitizes on nematode eggs, and thus, it is used as a good biocontrol agent against plant root-knot nematodes. However, little is known about the transcriptional response of P. lilacinum while infecting nematode eggs. This study presents the whole transcriptome sequencing of P. lilacinum and transcriptome-wide gene expression analysis of P. lilacinum upon infecting the eggs of Meloidogyne incognita compared to non-infecting controls. A transcriptomic library of P. lilacinum was used as reference gene set and six transcriptomic libraries of the non-infecting control and P. lilacinum infecting M. incognita eggs were constructed, respectively, comprising three biological replicates of each. A total of 1,011 differently expressed genes (DEGs) were identified in the infecting samples, including 553 up-regulated and 458 down-regulated genes compared to the non-infecting control samples. Furthermore, functional enrichment analysis exhibited that these DEGs were primarily involved in oxidative phosphorylation, oxidoreductase activity, and metabolic processes. Fifteen DEGs were randomly selected to verify the RNA sequencing results through quantitative real-time polymerase chain reaction (qPCR). The study focused on P. lilacinum genes that were strongly expressed upon infecting M. incognita eggs. These DEGs were primarily involved in detoxification, parasitic behavior, and nutritional utilization. This study contributes significantly to the understanding of the molecular mechanisms underlying the parasitic action of P. lilacinum on nematode eggs and provides a valuable genetic resource for further research on parasitic behavior of P. lilacinum. Notably, this study examined the transcriptomics of P. lilacinum infecting M. incognita eggs at only one time point. Since there were fungi at different stages of the infection process at that time point, the transcriptional profiles are not precisely examining one specific stage in this process. [ABSTRACT FROM AUTHOR]

Two isolations of fungi from a bank of microorganisms in the Biological Sciences Laboratory at Escuela Superior Politécnica de Chimborazo were tested on the galling caused by Meloidogyne incognita in tomato seedlings grown in pots with substrate infested with a suspension of nematodes, with approximately 2000 juvenile stages (J2) from root galls of plants infested with M. incognita, taken from the Nematology laboratory of the Ecuadorian Agricultural Quality Assurance Agency (AGROCALIDAD). Pleurotus ostreatus was a fungus with nematicidal characteristics through production of toxins; while Trichoderma harzianum is a widely known fungus, although it is a plant growth promoter rather than a nematicide. The two fungi were formulated in wheat straw and rabbit manure. A complete randomized design (CRD) with three replications was used, with a chemical control (Fenamiphos) and an absolute control. Five grams of each formulation was applied per plant before the transplant. The number of galls in the roots, plant height, stem diameter, number of leaves and fresh and dry weight of the aerial part and roots of 180 tomato plants grown in greenhouse were evaluated at 60 days after transplant. The results showed that the two fungi reduced the number of galls and made it possible to obtain dry weights of the aerial and radicular part very close to the chemical control (10.09 and 3.39 g) with 8.68; 8.04; 2.96 and 3.25 g respectively. Besides Trichoderma harzianum proved to be a good promoter of root growth, therefore, the use of these bioformulates is a promising measure for the control of this phytonematode

The objective of this study was to validate the application of P. chlamydosporia strain IMI SD 187 (a.i. of bionematicide KlamiC®) in the agronomic management strategy for plantain vitroplants (Musa paradisiaca L.) during the ex vitro adaptation phase. In a first assay, the in vitro compatibility of P. chlamydosporia, with the products FitoMas, Urea, Cuproflow, Bayfolan, and Dimethoate added to the culture medium, was evaluated, taking into account the fungal radial mycelial growth and sporulation. In a second assay, these products were combined with the strain IMI SD 187, during the acclimatization phase of vitroplants. P. chlamydosporia was applied at 5,6 x 105 clamidospore.vitroplant-1 by sprinkling the vitroplants at 3 and 20 days after transplanting, alone or in combination with agrochemicals and bioestimulant, on vitroplants of different size, cultivar 'CEMSA - ?'. The vitroplants were transplanted into polypropylene trays of 70 alveolus containing substrate: ferralitic red lixiviade soil and organic amendment (1:3 v/v); and they were distributed in the acclimatization area under randomize block design. The plant growth and fungal colonization on the substrate and roots were evaluated. Cuproflow was considered high toxic and the rest of the products evaluated were compatibles with the fungus. P. chlamydosporia colonized the vitroplants rhizosphere, and plant growth parameters were increased: plant length, pseudo-stem diameter and foliate and root fresh masses. The major growth stimulation was achieved on smaller size vitroplants. [ABSTRACT FROM AUTHOR]

The strain Purpureocillium sp. UdeA0106 is an antagonist of nematodes, fungi, and garden symphylans from crops with high economic importance in Colombia (Salazar ; Salazar et al. ; Cardona et al. ; Gallego et al. ) and is being studied to be proposed as new species. It was included on the 1000 fungal genomes project to elucidate its phylogenetic relationships with other fungi. Purpureocillium’s mitogenome has 23,495 bp of circular size. It contains 15 protein-coding genes without duplications (PCGs), corresponding to the 60% of its total length, 23 transfer genes (7.6% tRNA), two of them duplicated (trnR and trnM), and two ribosomal genes (17.6% rRNA) and a GC content of 28.44%. A phylogenetic tree was proposed using their 14 PCGs mitochondrial genes and was compared with other fungi of the Subphylum Pezizomycotina. Phylogenetics relationships showed UdeA0106 to be close to P. chlamydosporia and M. anisopliae forming a cluster with other fungal biocontrol agents and separated the strain of plant pathogenic fungi.

The nematophagous fungus Pochonia chlamydosporia, a natural enemy of plant parasitic nematodes (PPN), has been exploited in the development of sustainable management strategies for PPN control. The intrinsic variation among P. chlamydosporia isolates affects biocontrol potential, so sound characterisation is required. Biological, molecular and metabolic analyses can be determinant in the screening and selection of these potential biological control agents. This study aimed to provide integrative characterisation of P. chlamydosporia isolates that can support isolate selection for biological control purposes. Eight Portuguese isolates, associated with Meloidogyne spp., were used as a case study. Isolates were identified and characterised: i) at the biological level through standard bioassays to evaluate their ability for rhizosphere colonisation, to produce chlamydospores, and to parasitise Globodera pallida and Meloidogyne incognita eggs; ii) at the molecular level, examining genetic variation using ERIC-PCR; and iii) at the metabolic level, assessing their metabolic profiles using Biolog FF MicroPlates, with concurrent reads of fungal utilisation of 95 different carbon sources. Molecular data and metabolic characterisation were reduced using Principal Component Analysis and compared with the biological characteristics. Molecular profiles could only be related to isolate geographical origin, but the original substrate (eggs or roots), parasitism of M. incognita eggs and ability for rhizosphere colonisation were correlated with metabolic profiles, indicative of utilisation of specific carbon sources. Meloidogyne egg parasitism and rhizosphere colonisation were related to each other. This integrative characterisation offers novel perspectives on the biology and biocontrol potential of P. chlamydosporia, and, once tested on a broader set of isolates, could be used to assist rapid isolate selection.

Among pests and diseases affecting banana crops, which ultimately lead to yield losses, the presence of plant-parasitic nematodes, such as Radopholus similis, Helicotylenchus multicinctus, Pratylenchus coffeae, and Meloidogyne spp., are to be considered. The distribution of these pathogens in the field occurs mainly via propagative material. The objective of the present study was to evaluate banana suckers cv. Comprida, naturally infected by a mixed population of R. similis (3.21%), Helicotylenchus sp. (7.91%), Meloidogyne sp. (1.37%), and Pratylenchus sp. (87.51%), under greenhouse conditions, treated with Purpureocillium lilacinum (Lilacel® 1x108 CFU/ml). Five doses of the bionematicide were tested (0.2, 0.4, 0.6, 0.8, 1.0%), plus controls of Carbofuran (Furadan® 350 SC at 4 ml/L water) and water. Banana suckers were dipped in the treatment solutions for 60 min and planted in pots filled with sterilized soil. The experiment was performed in a completely randomized design with eight replicates. The percentage of emergence and the nematode population in the soil, rhizome, and roots, as well as the reproduction factor, were evaluated after 4 months. The regression analyses between the variables were represented by linear, quadratic, and square root models. Final nematode populations were reduced in all treatments when compared to the negative control (water). [ABSTRACT FROM AUTHOR]

The fungus Pochonia chlamydosporia (Pc) has been increasingly used to control plant-parasitic nematodes. This fungus also increases the uptake of nutrients by plants. However, the mechanisms by which Pc modifies the soil nutrient supply and, or the capacity of plants to acquire nutrients are not fully understood. In this research we investigated possible mechanisms that explain how Pc increases phosphorus uptake by plants. We tested the hypothesis that Pc produces phosphatases, which are enzymes that promote depolymerization of organic phosphate compounds. We further investigated if the known effect of Pc on inorganic phosphate (IP) solubilization could be credited to the release of organic acids and, if so, which organic acids are secreted by the fungus. Three isolates of the fungus (Pc-10, Pc-40, and Pc-46) were used in the study. We found that Pc can produce acid (Pc-10 = 0.0209 U/ml, Pc-40 = 0.0282 U/ml, Pc-46 = 0.0094 U/ml) and alkaline phosphatases (Pc-10 = 0.0490 U/ml, Pc-40 = 0.0000, Pc-46 = 0.0306 U/ml). All isolates were able to solubilize IP. The isolate Pc-10 solubilized higher amounts of phosphate (47.5 mg/l) compared to Pc-40 (37.9 mg/l) and Pc-46 (36.6 mg/l). We also identified three organic acids (acetic, citric, and propionic acid) produced by Pc-10. To our knowledge, this is the first report of Pc producing phosphatases and organic acids. [ABSTRACT FROM AUTHOR]

The aim of this work was to evaluate the effect of the strain IMI SD 187 of P. chlamydosporia var. catenulata as an endophyte on plant growth promotion of the black bean cv. 'Cuba Cueto 25-9' (CC 25-9 N). Two experiments were carried out, in vitro and under greenhouse conditions. In vitro, the bean seeds were coated with a mixture of the fungal spores and clay at different doses: 1, 5, 10 and 15% respect to the total weight of the seeds. A negative control with only disinfected seeds and a positive control of seeds coated with the clay (15 %) were used. The germination associated parameters in each treatment were compared. In the greenhouse experiment, the application of the fungus was evaluated by coating the seeds, applying a fungal suspension to the substrate, or by combining them, taking into account the rhizosphere colonization by the strain and the plant growth on the soil: organic fertilizer (3:1 v/v) substrate. The strain IMI SD 187 increased the in vitro germination parameters of the bean seeds, with a significant effect on hypocotyl length and fresh plant weight. High root colonization was achieved with two applications of the fungus, the endophytic root colonization was 16,67 % in 30 days and seed germination was advanced in two days. There was a tendency to increase the parameters number of trifoliate leaves, shoot length, fresh and dry plant weight, and fresh root weight, in different treatments with the fungus compared with the control treatment. [ABSTRACT FROM AUTHOR]

The nematophagous fungus Pochonia chlamydosporia, a natural enemy of plant parasitic nematodes (PPN), has been exploited in the development of sustainable management strategies for PPN control. The intrinsic variation among P. chlamydosporia isolates affects biocontrol potential, so sound characterisation is required. Biological, molecular and metabolic analyses can be determinant in the screening and selection of these potential biological control agents. This study aimed to provide integrative characterisation of P. chlamydosporia isolates that can support isolate selection for biological control purposes. Eight Portuguese isolates, associated with Meloidogyne spp., were used as a case study. Isolates were identified and characterised: i) at the biological level through standard bioassays to evaluate their ability for rhizosphere colonisation, to produce chlamydospores, and to parasitise Globodera pallida and Meloidogyne incognita eggs; ii) at the molecular level, examining genetic variation using ERICPCR; and iii) at the metabolic level, assessing their metabolic profiles using Biolog FF MicroPlates, with concurrent reads of fungal utilisation of 95 different carbon sources. Molecular data and metabolic characterisation were reduced using Principal Component Analysis and compared with the biological characteristics. Molecular profiles could only be related to isolate geographical origin, but the original substrate (eggs or roots), parasitism of M. incognita eggs and ability for rhizosphere colonisation were correlated with metabolic profiles, indicative of utilisation of specific carbon sources. Meloidogyne egg parasitism and rhizosphere colonisation were related to each other. This integrative characterisation offers novel perspectives on the biology and biocontrol potential of P. chlamydosporia, and, once tested on a broader set of isolates, could be used to assist rapid isolate selection. [ABSTRACT FROM AUTHOR]

The complete mitochondrial genome of Purpureocillium lavendulum was characterized in this study. This mitogenome is a closed circular molecule of 23,567 bp in length with a GC content of 28.46%, including 15 protein-coding genes, 25 transfer RNA genes, 2 ribosomal RNA genes. Phylogenetic analyses based on sequences at the 14 concatenated mitochondrial protein-coding genes showed that P. lavendulum was closely related to Hirsutella minnesotensis. [ABSTRACT FROM AUTHOR]

The fungus Pochonia chlamydosporia is one of the most studied biological agents used to control plant-parasitic nematodes. This study found that the isolates Pc-3, Pc-10 and Pc-19 of this fungus promote the growth of tomato and lettuce seedlings. The isolate Pc-19 colonized the rhizoplane of tomato seedlings in only 15 days and produced a large quantity of chlamydospores. This isolate was able to use cellulose as a carbon source, in addition to glucose and sucrose. Scanning electron microscopy (SEM) revealed that hyphae of the P. chlamydosporia isolate Pc-10 penetrated the epidermal cells of the tomato roots. These three P. chlamydosporia isolates promote the growth of tomato and lettuce.

Abstract The treatment of seeds with biological control agents is one of the most convenient methods of introducing microorganisms into the root environment. Pochonia chlamydosporia is a promising biological control agent of plant-parasitic nematodes and a good root colonizer. Seed treatment with this fungus would make its application viable for soybean and grain crops. Therefore, the aim of the present work was to evaluate the influence of soil texture under the development of P. chlamydosporia applied as a seed dressing to control Meloidogyne incognita in soybean greenhouse. Soybean seeds treated with P. chlamydosporia were sown in PVC (55 cm × 10 cm) tubes containing clayey or sandy soil infested with M. incognita eggs. Sixty days after sowing, the tubes were sectioned into four parts (0.0–12.5, 12.5–25.0, 25.0–37.5, and 37.5–50.0 cm of length) to evaluate the percolation and multiplication of P. chlamydosporia at four different soil depths. The development of P. chlamydosporia in the absence of the nematode was also evaluated. It was possible to verify soil colonization by P. chlamydosporia throughout the profile of both soils tested. The fungus was able to percolate in the soil up to at least 50 cm depth and was efficient in controlling M. incognita in both sandy and clayey soils; however, in the sandy soil, the fungus presented greater colonization and percolation, which may explain why it is more efficient in controlling the nematode when applied in sandy soil. Highlights • Pochonia chlamydosporia colonize throughout the profile of both sandy and clayey soils. • The fungus is efficient in controlling M. incognita in both sandy and clayey soils. • P. chlamydosporia , when applied through seed treatment, is able to colonize and protect the root system. [ABSTRACT FROM AUTHOR]

Abstract Biological control through the use of nematophagous fungi is a sustainable alternative for combatting helminthes in domestic animals and allows a reduction in the use of anthelmintics. The objective of this research was to evaluate the efficacy of the Arthrobotrys cladodes var macroides fungus in a pelleted formulation, based on sodium alginate and administered twice a week orally, as an alternative for the biological control of nematodes in field-grown young cattle. The experiment was conducted in a farm located in the municipality of Viçosa, MG, where 12 cattle, seven to nine months old, were allocated in two groups (treated group and control group) and distributed in pickets of Brachiaria decumbens , naturally infested with nematode larvae. The animals in the treated group received 1g of sodium alginate matrix pellets for every 10 kg of animal live weight, containing the nematophagous fungus Arthrobotrys cladodes var macroides and administered twice a week in conjunction with commercial feed. In the control group, each animal received 1 g of pellets for every 10 kg of animal live weight, without fungal mycelium added to the feed. Samples of feces and pastures were collected fortnightly for 12 months. The results showed that the most prevalent nematode genera in the coprocultures were Haemonchus sp., Cooperia sp. and Oesophagostomum sp., reflecting the results found in forage. The pasture that contained the animals that received feed with the fungus presented a reduction of 59% and 52% of larvae recovered at distances of 20 cm and 40 cm from the fecal pats, respectively. The mean number of eggs per gram of feces each month and animal body weight did not differ (p > 0.05) between the treated and control groups. Stool and soil samples from both groups were colonized by A. cladodes fungus and other fungi. Administration of Arthrobotrys cladodes var macroides mycelium by means of a sodium alginate matrix twice weekly reduced larval infestation of the surrounding pasture, indicating that this fungus may be a promising biological control of infecting forms of nematodes present in the environment. Graphical abstract Image Highlights • We evaluate the efficacy of the Arthrobotrys cladodes fungus in pellets as an alternative for the biological control. • A. cladodes var. macroides isolated from Brazilian soil shows high production of conidia and produces chlamydospores. • The most prevalent nematode genera in the coprocultures were Haemonchus sp., Cooperia sp. and Oesophagostomum sp. • A. cladodes reduced at 59% and 52% the number of larvae recovered in the pasture. [ABSTRACT FROM AUTHOR]