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Stéphane Declerck - One of the best experts on this subject based on the ideXlab platform.
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Life Cycle of Glomus Species in Monoxenic Culture
Soil Biology, 2005Co-Authors: Yolande Dalpé, Francisco Adriano De Souza, Stéphane DeclerckAbstract:With respect to the Glomeromycota taxonomy, the genus Glomus includes close to 110 described species, making this genus themost important of the order Glomerales (Schusler et al. 2001). As a consequence, a large number of research investigationsonAMfungi arebasedonGlomus species isolates. Even though a limited number of species are cultivated under Monoxenic Culture, a huge amount of knowledge has already been generated to draw a reliable picture of their life cycle. The potential of this technology, although still in its infancy, has already influenced and stimulated research investigations notably in colony growth kinetics and sporulation (Fortin et al. 2002). With respect to the Glomus species life cycle, this review is subdivided into fourmajor sections: (1) the spore germination, (2) the pre-symbiotic stage, (3) the host root connection, and (4) the symbiotic stage.
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Life History Strategies in Gigasporaceae: insight from Monoxenic Culture
Soil Biology, 2005Co-Authors: Francisco Adriano De Souza, Stéphane Declerck, Yolande Dalpé, Ivan Enrique De La Providencia, Nathalie Séjalon-delmasAbstract:During the past years, there has been an increased interest in the role of arbuscular mycorrhizal (AM) fungal biodiversity for the functioning of terrestrial ecosystems and in the application of AM fungal technology for agricultural and land rehabilitation schemes. However, one major bottleneck in AM research is the lack of knowledge on ecology, and in particular on life history strategies (LHS) among the different AM fungal families (Hart et al. 2001; Hart and Klironomos 2002). The LHS of an organism is a product of its evolutionary past, and is expressed in the fungal life cycle, i.e. patterns of growth, differentiation, storage and, especially, reproduction (Begon et al. 1996). In order to understandAM fungal ecology, it is central to appreciate species life history traits and genetic diversity. Monoxenic Cultures of AM fungi are exploited here to study these issues, with special emphasis on the family Gigasporaceae.
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Mycelium Development and Architecture, and Spore Production of Scutellospora reticulata in Monoxenic Culture with Ri T-DNA Transformed Carrot Roots
Mycologia, 2003Co-Authors: Francisco Adriano De Souza, Stéphane DeclerckAbstract:Mycelium development and architecture and spore production were studied in Scutellospora reticulata from single-spore isolates grown with Ri T-DNA transformed carrot root-organ Culture in Monoxenic system. Culture establishment, anastomosis occurrence and auxiliary cell development also were examined. Seventy percent of the pregerminated disinfected spores colonized the transformed carrot roots. After 8 mo, the average spore production was 56 (24–130) per 30 cm3 of medium. Of the spores produced, 75% germinated and produced new generations in Monoxenic Culture. The mycelium network was formed by thick light-brown hyphae, which exhibit two major architecture patterns related to either root colonization or resource exploitation, and lower-order hyphae, bearing auxiliary cells, branched absorbing structures (BAS), hyphal swellings (HS) and forming anastomoses. BAS were formed abundantly in extramatrical mycelium and frequently had HS resembling vesicles, a feature not previously reported in the Gigasporaceae, to the best of our knowledge. Few anastomosis were observed within the mycelium and most often corresponded to a healing mechanism that form hypha bridges to reconnect broken hyphae or overcoming obstructed areas within a hypha. Numerous auxiliary cells were produced during Culture development and their role was inferred. [KEYWORDS: anastomosis, arbuscular mycorrhizal fungi, auxiliary cell, branched absorbing structures, Gigasporaceae, Glomeromycota, hyphal swelling, Monoxenic Culture
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Mycelium development and architecture, and spore production of Scutellospora reticulata in Monoxenic Culture with Ri T-DNA transformed carrot roots
Mycologia, 2003Co-Authors: Francisco Adriano De Souza, Stéphane DeclerckAbstract:Mycelium development and architecture and spore production were studied in Scutellospora reticulata from single-spore isolates grown with Ri T-DNA transformed carrot root-organ Culture in Monoxenic system. Culture establishment, anastomosis occurrence and auxiliary cell development also were examined. Seventy percent of the pregerminated disinfected spores colonized the transformed carrot roots. After 8 mo, the average spore production was 56 (24-130) per 30 cm(3) of medium. Of the spores produced, 75% germinated and produced new generations in Monoxenic Culture. The mycelium network was formed by thick light-brown hyphae, which exhibit two major architecture patterns related to either root colonization or resource exploitation, and lower-order hyphae, bearing auxiliary cells, branched absorbing structures (BAS), hyphal swellings (HS) and forming anastomoses. BAS were formed abundantly in extramatrical mycelium and frequently had HS resembling vesicles, a feature not previously reported in the Gigasporaceae, to the best of our knowledge. Few anastomosis were observed within the mycelium and most often corresponded to a healing mechanism that form hypha bridges to reconnect broken hyphae or overcoming obstructed areas within a hypha. Numerous auxiliary cells were produced during Culture development and their role was inferred.
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Modelling the sporulation dynamics of arbuscular mycorrhizal fungi in Monoxenic Culture
Mycorrhiza, 2001Co-Authors: Stéphane Declerck, Sylvie Cranenbrouck, Le E. BoulengéAbstract:Spore production of arbuscular mycorrhizal fungi is important in inoculum production, and Monoxenic Culture is a promising way to produce large amounts of contaminant-free inoculum. Mass production of spores is therefore essential and mathematical models useful as descriptive and predictive tools of sporulation dynamics. We followed the sporulation dynamics of three Glomus strains i.e. G. intraradices, G. proliferum and G. caledonium, Cultured Monoxenically on a nutrient agar medium containing macro- and microelements, vitamins and sucrose. Three models (Schnute, logistic, and Gompertz) were fitted to the data and compared in order to select the most adequate model. The Schnute model was the reference against which the two other models were tested. For all three Glomus strains examined, the sporulation dynamics followed a sigmoidal curve with a lag, a log, and a plateau phase. Visually, all three models fitted the data very well, with R 2 values ranging from 0.9703 to 0.9995. They thus appeared adequate for describing the temporal dynamics of spore production. In most cases the Gompertz model described sporulation as accurately as the Schnute model, but the performance of the logistic model was seldom as good. The Gompertz model is thus convenient for modelling the sporulation dynamics of Glomus strains grown in a well-defined nutrient agar medium. As such, its use may facilitate and help improve exploitation of Monoxenic Culture systems.
Norberto Chavarría-hernández - One of the best experts on this subject based on the ideXlab platform.
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Production of entomopathogenic nematodes in submerged Monoxenic Culture: A review.
Biotechnology and bioengineering, 2020Co-Authors: Carlos I. Cortés-martínez, Norberto Chavarría-hernándezAbstract:Monoxenic liquid Culture is the most suitable technology for scaling up to industrial production of entomopathogenic nematodes (EPNs); however, the variability of the yield production remains a current problem in the process. The aim of this study was to analyze the parameters and criteria for EPN production in liquid Culture based on scientific and technological knowledge from the last two decades. While experimental research has permitted the yield production of Heterorhabditis bacteriophora (362 × 103 infective juveniles [IJs]/ml) and Steinernema carpocapsae (252 × 103 IJs/ml), simultaneously, theoretical approaches have contributed to the understanding of the Culture process, based on biological parameters of the bacterium-nematode complex and hydrodynamic and rheological parameters of the complex gas-liquid-solid system. Under this interdisciplinary research approach, bioprocess and biosystem engineering can contribute to design the various control strategies of the process variables, increase the productivity, and reduce the variability that until now distinguishes the in vitro production of EPNs by the liquid Culture.
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Mass production of the entomopathogenic nematode, Steinernema carpocapsae CABA01, through the submerged Monoxenic Culture in two internal-loop airlift bioreactors with some geometric differences
Biochemical Engineering Journal, 2011Co-Authors: Norberto Chavarría-hernández, Gabriela Maciel-vergara, Juan-carlos Chavarría-hernández, Javier Castro-rosas, Blanca-rosa Rodríguez-pastrana, Mayra De La Torre-martínez, Adriana-inés Rodríguez-hernándezAbstract:Abstract The submerged Monoxenic Culture of the entomopathogenic nematode, Steinernema carpocapsae CABA01, was carried out in two internal-loop airlift reactors (R1 and R2) with some geometric differences. Two runs each reactor were carried out at operating conditions VL = 4.22 L, Q = 1–1.5 vvm, T = 22 °C. The Culture broth apparent viscosity changed from 2 to 12 mPa s determining global changes in both hydrodynamics (expressed as the dimensionless Reynolds number, Re) and oxygen transfer conditions (expressed as the kLa coefficient). Such changes were 170
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Kinetics of infective juvenile production of the entomopathogenic nematode Steinernema carpocapsae in submerged Monoxenic Culture
Bioprocess and Biosystems Engineering, 2008Co-Authors: Norberto Chavarría-hernández, Gabriela Maciel-vergara, Marco-antonio Islas-lópez, Martha Gayosso-canales, Adriana-inés Rodríguez-hernándezAbstract:The effects of Culture medium formulations on the kinetics of infective juvenile (IJ) production of the entomopathogenic nematode Steinernema carpocapsae in submerged Monoxenic Culture, were studied at the cylindrical-bottle scale using six Culture media containing agave juice from Agave spp. among other ingredients. The IJ production kinetics was well modelled through a re-parameterised 3-parameter Gompertz model with kinetic parameters: IJ-lag phase λ _IJ (day), maximum IJ-stage production rate m _max (day^−1), and IJ-multiplication factor ( C _IJ/ C _IJ,0)_max(−). The variation of λ _IJ was not very important within fermentations (10.3–16.2 days); nonetheless, important effects were observed on m _max (32.8–241.2 days^−1) and ( C _IJ/ C _IJ,0)_max (66(−) to 611.4(−)). Particularly, maximum values of m _max and ( C _IJ/ C _IJ,0)_max were obtained in medium A4 (0.276 l l^−1 agave juice, 17 g l^−1 yeast extract, 12 g l^−1 dried egg yolk, 0.025 l l^−1 corn oil). Also, the maximum IJ concentration (249,444 per ml) was achieved in A4-fermentations.
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Evolution of Culture broth rheological properties during propagation of the entomopathogenic nematode Steinernema carpocapsae, in submerged Monoxenic Culture.
Biotechnology progress, 2003Co-Authors: Norberto Chavarría-hernández, Adriana-inés Rodríguez-hernández, Fermín Pérez-guevara, Mayra De La TorreAbstract:This article presents the evolution of Culture broth rheological properties during Monoxenic Cultures of Steinernema carpocapsae in cylindrical bottles agitated orbitally. Rheological properties were evaluated in simple-shear flow conditions and were well-modeled by the Ostwald-de Waele model. Rheological properties varied from slightly dilatant, n = 1.2 (-), to moderately pseudoplastic flow behavior, n = 0.6 (-). Nematode concentrations increased from 750 +/- 190 to 130 900 +/- 6900 nematodes/mL, and the apparent viscosity (eta(a)) evolved from 4.5 +/- 0.7 to 46.6 +/- 3.2 mPa.s during the fermentations. Rheological behavior did not appear to be strongly influenced by nematode number and/or its stage of development; however, the release of substances from the decomposition of nematode cadavers appeared to be of great importance. Among the different developmental stages of the nematodes, only juveniles of the first stage (J1) were highly susceptible to the shearing conditions tested (shear stress, tau(r)()(theta), from 0.9 to 3.5 Pa during periods of 80-100 min), resulting in the viability loss of 85% of J1 nematodes.
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Population growth kinetics of the nematode, Steinernema feltiae, in submerged Monoxenic Culture
Biotechnology Letters, 2001Co-Authors: Norberto Chavarría-hernández, Mayra De La TorreAbstract:Monoxenic Cultures of the nematode, Steinernema feltiae, were carried out on two complex liquid media: P1, mainly soybean flour/egg yolk/yeast extract, and P2, mainly egg yolk/yeast extract. Up to 140 000–200 000 nematodes ml−1 were produced within 7 days, and more than 95% of the final population was in the infective juvenile stage. The total nematode concentration growth curve had a sigmoidal shape. Nematode population growth kinetics were modelled using a re-parameterised Gompertz model. Yeast extract concentration appeared to be a key factor for obtaining high nematode concentrations.
Adriana-inés Rodríguez-hernández - One of the best experts on this subject based on the ideXlab platform.
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Mass production of the entomopathogenic nematode, Steinernema carpocapsae CABA01, through the submerged Monoxenic Culture in two internal-loop airlift bioreactors with some geometric differences
Biochemical Engineering Journal, 2011Co-Authors: Norberto Chavarría-hernández, Gabriela Maciel-vergara, Juan-carlos Chavarría-hernández, Javier Castro-rosas, Blanca-rosa Rodríguez-pastrana, Mayra De La Torre-martínez, Adriana-inés Rodríguez-hernándezAbstract:Abstract The submerged Monoxenic Culture of the entomopathogenic nematode, Steinernema carpocapsae CABA01, was carried out in two internal-loop airlift reactors (R1 and R2) with some geometric differences. Two runs each reactor were carried out at operating conditions VL = 4.22 L, Q = 1–1.5 vvm, T = 22 °C. The Culture broth apparent viscosity changed from 2 to 12 mPa s determining global changes in both hydrodynamics (expressed as the dimensionless Reynolds number, Re) and oxygen transfer conditions (expressed as the kLa coefficient). Such changes were 170
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Kinetics of infective juvenile production of the entomopathogenic nematode Steinernema carpocapsae in submerged Monoxenic Culture
Bioprocess and Biosystems Engineering, 2008Co-Authors: Norberto Chavarría-hernández, Gabriela Maciel-vergara, Marco-antonio Islas-lópez, Martha Gayosso-canales, Adriana-inés Rodríguez-hernándezAbstract:The effects of Culture medium formulations on the kinetics of infective juvenile (IJ) production of the entomopathogenic nematode Steinernema carpocapsae in submerged Monoxenic Culture, were studied at the cylindrical-bottle scale using six Culture media containing agave juice from Agave spp. among other ingredients. The IJ production kinetics was well modelled through a re-parameterised 3-parameter Gompertz model with kinetic parameters: IJ-lag phase λ _IJ (day), maximum IJ-stage production rate m _max (day^−1), and IJ-multiplication factor ( C _IJ/ C _IJ,0)_max(−). The variation of λ _IJ was not very important within fermentations (10.3–16.2 days); nonetheless, important effects were observed on m _max (32.8–241.2 days^−1) and ( C _IJ/ C _IJ,0)_max (66(−) to 611.4(−)). Particularly, maximum values of m _max and ( C _IJ/ C _IJ,0)_max were obtained in medium A4 (0.276 l l^−1 agave juice, 17 g l^−1 yeast extract, 12 g l^−1 dried egg yolk, 0.025 l l^−1 corn oil). Also, the maximum IJ concentration (249,444 per ml) was achieved in A4-fermentations.
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Evolution of Culture broth rheological properties during propagation of the entomopathogenic nematode Steinernema carpocapsae, in submerged Monoxenic Culture.
Biotechnology progress, 2003Co-Authors: Norberto Chavarría-hernández, Adriana-inés Rodríguez-hernández, Fermín Pérez-guevara, Mayra De La TorreAbstract:This article presents the evolution of Culture broth rheological properties during Monoxenic Cultures of Steinernema carpocapsae in cylindrical bottles agitated orbitally. Rheological properties were evaluated in simple-shear flow conditions and were well-modeled by the Ostwald-de Waele model. Rheological properties varied from slightly dilatant, n = 1.2 (-), to moderately pseudoplastic flow behavior, n = 0.6 (-). Nematode concentrations increased from 750 +/- 190 to 130 900 +/- 6900 nematodes/mL, and the apparent viscosity (eta(a)) evolved from 4.5 +/- 0.7 to 46.6 +/- 3.2 mPa.s during the fermentations. Rheological behavior did not appear to be strongly influenced by nematode number and/or its stage of development; however, the release of substances from the decomposition of nematode cadavers appeared to be of great importance. Among the different developmental stages of the nematodes, only juveniles of the first stage (J1) were highly susceptible to the shearing conditions tested (shear stress, tau(r)()(theta), from 0.9 to 3.5 Pa during periods of 80-100 min), resulting in the viability loss of 85% of J1 nematodes.
Francisco Adriano De Souza - One of the best experts on this subject based on the ideXlab platform.
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Life Cycle of Glomus Species in Monoxenic Culture
Soil Biology, 2005Co-Authors: Yolande Dalpé, Francisco Adriano De Souza, Stéphane DeclerckAbstract:With respect to the Glomeromycota taxonomy, the genus Glomus includes close to 110 described species, making this genus themost important of the order Glomerales (Schusler et al. 2001). As a consequence, a large number of research investigationsonAMfungi arebasedonGlomus species isolates. Even though a limited number of species are cultivated under Monoxenic Culture, a huge amount of knowledge has already been generated to draw a reliable picture of their life cycle. The potential of this technology, although still in its infancy, has already influenced and stimulated research investigations notably in colony growth kinetics and sporulation (Fortin et al. 2002). With respect to the Glomus species life cycle, this review is subdivided into fourmajor sections: (1) the spore germination, (2) the pre-symbiotic stage, (3) the host root connection, and (4) the symbiotic stage.
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Life History Strategies in Gigasporaceae: insight from Monoxenic Culture
Soil Biology, 2005Co-Authors: Francisco Adriano De Souza, Stéphane Declerck, Yolande Dalpé, Ivan Enrique De La Providencia, Nathalie Séjalon-delmasAbstract:During the past years, there has been an increased interest in the role of arbuscular mycorrhizal (AM) fungal biodiversity for the functioning of terrestrial ecosystems and in the application of AM fungal technology for agricultural and land rehabilitation schemes. However, one major bottleneck in AM research is the lack of knowledge on ecology, and in particular on life history strategies (LHS) among the different AM fungal families (Hart et al. 2001; Hart and Klironomos 2002). The LHS of an organism is a product of its evolutionary past, and is expressed in the fungal life cycle, i.e. patterns of growth, differentiation, storage and, especially, reproduction (Begon et al. 1996). In order to understandAM fungal ecology, it is central to appreciate species life history traits and genetic diversity. Monoxenic Cultures of AM fungi are exploited here to study these issues, with special emphasis on the family Gigasporaceae.
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Mycelium Development and Architecture, and Spore Production of Scutellospora reticulata in Monoxenic Culture with Ri T-DNA Transformed Carrot Roots
Mycologia, 2003Co-Authors: Francisco Adriano De Souza, Stéphane DeclerckAbstract:Mycelium development and architecture and spore production were studied in Scutellospora reticulata from single-spore isolates grown with Ri T-DNA transformed carrot root-organ Culture in Monoxenic system. Culture establishment, anastomosis occurrence and auxiliary cell development also were examined. Seventy percent of the pregerminated disinfected spores colonized the transformed carrot roots. After 8 mo, the average spore production was 56 (24–130) per 30 cm3 of medium. Of the spores produced, 75% germinated and produced new generations in Monoxenic Culture. The mycelium network was formed by thick light-brown hyphae, which exhibit two major architecture patterns related to either root colonization or resource exploitation, and lower-order hyphae, bearing auxiliary cells, branched absorbing structures (BAS), hyphal swellings (HS) and forming anastomoses. BAS were formed abundantly in extramatrical mycelium and frequently had HS resembling vesicles, a feature not previously reported in the Gigasporaceae, to the best of our knowledge. Few anastomosis were observed within the mycelium and most often corresponded to a healing mechanism that form hypha bridges to reconnect broken hyphae or overcoming obstructed areas within a hypha. Numerous auxiliary cells were produced during Culture development and their role was inferred. [KEYWORDS: anastomosis, arbuscular mycorrhizal fungi, auxiliary cell, branched absorbing structures, Gigasporaceae, Glomeromycota, hyphal swelling, Monoxenic Culture
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Mycelium development and architecture, and spore production of Scutellospora reticulata in Monoxenic Culture with Ri T-DNA transformed carrot roots
Mycologia, 2003Co-Authors: Francisco Adriano De Souza, Stéphane DeclerckAbstract:Mycelium development and architecture and spore production were studied in Scutellospora reticulata from single-spore isolates grown with Ri T-DNA transformed carrot root-organ Culture in Monoxenic system. Culture establishment, anastomosis occurrence and auxiliary cell development also were examined. Seventy percent of the pregerminated disinfected spores colonized the transformed carrot roots. After 8 mo, the average spore production was 56 (24-130) per 30 cm(3) of medium. Of the spores produced, 75% germinated and produced new generations in Monoxenic Culture. The mycelium network was formed by thick light-brown hyphae, which exhibit two major architecture patterns related to either root colonization or resource exploitation, and lower-order hyphae, bearing auxiliary cells, branched absorbing structures (BAS), hyphal swellings (HS) and forming anastomoses. BAS were formed abundantly in extramatrical mycelium and frequently had HS resembling vesicles, a feature not previously reported in the Gigasporaceae, to the best of our knowledge. Few anastomosis were observed within the mycelium and most often corresponded to a healing mechanism that form hypha bridges to reconnect broken hyphae or overcoming obstructed areas within a hypha. Numerous auxiliary cells were produced during Culture development and their role was inferred.
Michael T. Wilson - One of the best experts on this subject based on the ideXlab platform.
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The slug parasitic nematode Phasmarhabditis hermaphrodita associates with complex and variable bacterial assemblages that do not affect its virulence.
Journal of invertebrate pathology, 2010Co-Authors: Robbie Rae, Maria Tourna, Michael T. WilsonAbstract:Phasmarhabditis hermaphrodita is a nematode parasite of slugs that is commercially reared in Monoxenic Culture with the bacterium Moraxella osloensis and sold as a biological molluscicide. However, its bacterial associations when reared in vivo in slugs are unknown. We show that when reared in vivo in slugs, P. hermaphrodita does not retain M. osloensis and associates with complex and variable bacterial assemblages that do not influence its virulence. This is in marked contrast to the entomopathogenic nematodes that form highly specific mutualistic associations with Enterobacteriaceae that are specifically retained during in vivo growth.
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Monoxenic Culture of the slug parasite Phasmarhabditis hermaphrodita (Nematoda : Rhabditidae) with different bacteria in liquid and solid phase
Fundamental and applied nematology, 1995Co-Authors: Michael T. Wilson, David M. Glen, Pearce Jeremy David, P.b. RodgersAbstract:Summary- Sixteen bacterial isolates representing thineen species were tested for their ability to support growth of Phasmarhabditis hermaphroditain Monoxenic Cultures in Petri dishes of agar medium. Thirteen isolates were associated with the nematode in living or dead slugs (DeroGeras reticulaLUm) or in xenic Culture. Growth of P. he17naphrodila was obtained on ail isolates but its reproductive capacity differed considerably when Cultured with different bacteria. Five species of bacteria which supported vigorous growth of P. hermaphrodita on kidney agar were used to grow it in liquid Cultures. Ali supported growth and reproduction but there were significant differences in fmal numbers of nematodes and numbers of dauer larvae forrned. The differences in total numbers were not consistent with differences seen in Petri dish Cultures. Providencia rettgeri was found to give the best yields of dauer larvae in liquid Culture. ln both liquid and solid phase, Monoxenic growth of P. hermaphroditawas bener on media based on pig kidney than on wholly soluble media. Resume - Elevage du parasite de limace Phasmarhabditis hermaphrodita (Nernatoda: Rhabditidae) en milieu liquide et solide avec differentes bacteries- Seize isolats bacteriens, representant treize especes, ont ete testes pour leur capacite a maintenir la croissance de Phasmarhabditis hermaphrodita en Culture monoxenique sur agar, en boite de Petri. Tous les isolats permenent la croissance de P. hermaphrodita, mais la capacite de reproduction varie considerablement suivant les differentes bacteries. Cinq especes de bacteries ayant permis une croissance vigoureuse de P. hermaphroditaont ete utilisees pour son elevage en milieu liquide. Toutes permenent la croissance et la reproduction du nematode mais des differences significatives se produisent en ce qui concerne le nombre total de nematodes et celui des dauer larvae formees. Les differences entre les chiffres totaux ne sont pas significativement differentes de celles observees dans le cas de Culture en boites de Petri. En milieu liquide, Providencia rettgen' parait produire les meilleurs rendements en dauer larvae. Tant en milieu solide que liquide, la croissance monoxenique de P. hermaphrodita est meilleure sur des milieux a base de rognon de porc que sur des milieux ne comportant que des elements entierement solubles.