Pierre Camporota

Bio: Pierre Camporota is an academic researcher. The author has an hindex of 3, co-authored 4 publications receiving 55 citations.

Antagonisme in vitro de Trichoderma spp. vis-à-vis de Rhizoctonia solani Kühn

Abstract: Cet article presente les resultats obtenus lors de la realisation de la premiere etape d'un programme de selection de souches de Trichoderma spp. utilisables pour la lutte biologique contre Rhizoctonia solani dans le sol: 28 souches de Trichoderma ont ete confrontees in vitro a 3 souches de R. solani appartenant a des groupes d'anastomose differents. On a mesure, pour chaque souche de Trichoderma, la capacite a envahir les colonies de l'agent pathogene ainsi que les 3 modes d'action: mycoparasitisme, emission de substances inhibitrices non volatiles et volatiles. les 3 souches de R. solani ont montre des differences de sensibilite de l'antagoniste. L'effet inhibiteur de Trichoderma varie aussi en fonction des souches. Des observations au cours de l'experimentation ainsi que des correlations faites entre la capacite de colonisation de Trichoderma et les mesures des 3 modes d'action ont revele que les souches de R. solani le plus rapidement detruites etaient celles touchees par le mycoparasitisme. L'etude de l'antagonisme in vivo en utilisant les memes souches pathogenes et antagonistes sera la deuxieme etape de ce programme

Mesure de la colonisation saprophytique en compétition de Rhizoctonia solani Kühn dans les sols et substrats

Abstract: R. solani, Piégeage, Compétition saprophytique Une méthode de piégeage de Rhizoctonia solani Kühn a été mise au point afin de pouvoir estimer son aptitude à la compétition saprophytique dans les sols et substrats. Le parasite est piégé au moyen de rondelles de papier filtre imprégnées de milieu sélectif et enfouies dans la terre à analyser ; les rondelles sont retirées au bout de 5 jours et déposées sur un milieu gélosé afin de déterminer le pourcentage de pièges colonisés par le Rhizoctonia solani. La méthode est quantifiée en faisant varier la concentration de terre à analyser par dilution avec un sol désinfecté. Une relation linéaire est calculée entre les pourcentages de pièges colonisés et les concentrations de terre correspondantes. Quatre sols ont été analysés par cette méthode ; l’interprétation et l’utilisation des résultats sont discutés.

Microbiological methods for assessing soil quality

Abstract: This book provides a selection of microbiological methods that are already applied in regional or national soil quality monitoring programs. It is split into two parts: part one gives an overview of approaches to monitoring, evaluating and managing soil quality. Part two provides a selection of methods, which are described in sufficient detail to use the book as a practical handbook in the laboratory. The methods are described in chapters on soil microbial biomass and numbers, soil microbial activity, soil microbial diversity and community composition, and plant-microbe interactions and soil quality.

Biological control of seedling blight of wheat caused by Fusarium graminearum with beneficial rhizosphere microorganisms

Abstract: Fusarium graminearum is associated with the cereal damping-off complex which reduces germination, seedling stand and yield. Fifty-two bacterial strains and six Trichoderma spp. isolated from the wheat rhizosphere were evaluated for biocontrol of seedling blight of wheat caused by F. graminearum. Their potential as biocontrol agents was tested in vitro and in the greenhouse. Isolates varied in their ability to inhibit the mycelial growth of F. graminearum in agar plate bioassays by 0–79%. This parameter was not related with biocontrol efficacy of in vivo assays. In greenhouse trials, all isolates were initially evaluated for reducing disease on wheat cultivars Klein Centauro (moderately resistant to F. graminearum) and Pro INTA Oasis (susceptible) planted in sterilized soil artificially infested with the pathogen. Among the 25 bacteria and six fungal isolates that exhibited a pronounced suppressive effect, the most efficient 10 for both cultivars were further assayed on eight cultivars (Buck Candil, Buck Catriel, Buck Chambergo, Buck Poncho, Buck Topacio, Klein Cacique, Klein Centauro and Pro INTA Oasis) potted in cultivated–inoculated soil. Three weeks after sowing, plant stand, percentage of diseased emerging seedlings, plant height and dry weight were evaluated. Among the antagonists only Stenotrophomonas maltophilia was significantly better than the control for the average of the eight cultivars for plant stand, height and dry weight. Stenotrophomonas maltophilia also caused a non-significant decrease in the percentage of diseased plants. Three strains of Bacillus cereus and one isolate of Trichoderma harzianum gave also a good control in some cultivars. The ability of these isolates to affect the infection of wheat seedlings by F. graminearum may be of potential value in field trials.

Interactions between Trichoderma koningii, Fusarium solani and Glomus mosseae: Effects on plant growth, arbuscular mycorrhizas and the saprophyte inoculants

Abstract: The effect of inoculation with the saprophytic fungi Trichoderma koningii and Fusarium solani on maize ( Zea mays ) and lettuce ( Lactuca sativa ) with or without arbuscular mycorrhizal (AM) colonization by Glomus mosseae was studied in a greenhouse trial. Plant dry wt of non-AM inoculated maize and lettuce were unaffected by the presence of T. koningii and F. solani . In contrast, T. koningii decreased plant dry wt and AM colonization when inoculated into the rhizosphere before or at the same time as G. mosseae . In addition, the T. koningii population was considerably reduced when G. mosseae was inoculated 2 weeks before the saprophytic fungus. At this time T. koningii did not affect the proportion of the root length colonized by G. mosseae , but did adversely affect its metabolic activity assessed as succinate dehydrogenase activity. Although F. solani did not affect AM colonization of maize roots, its effect on AM colonization of lettuce roots was similar to that of T. koningii . The population of F. solani decreased significantly in the rhizosphere of both plants. The possible mechanisms of interaction between the saprophytic fungi and G. mosseae are discussed.

Interactions between Glomus mosseae and arbuscular mycorrhizal sporocarp-associated saprophytic fungi

Abstract: The saprophytic fungi Wardomyces inflatus (Marchal) Hennebert, Paecilomyces farinosus (Holm G G. roseum, T. pseudokoningiiand T. harzianum had no effect on germination; and P. farinosus and SDM-54 increased the percentage of spore germination of G. mosseae after 4 d. Wardomyces inflatus significantly decreased hyphal length of spores which germinated, but no other saprophytic fungi affected hyphal growth. Trichoderma pseudokoningii, T. harzianum , P. farinosus and SDM-54 increased the number of auxiliary cells formed by G. mosseae. The effect of saprophytic fungi on arbuscular mycorrhizal colonization of soybean was studied in a greenhouse trial. The percentage of soybean root length colonized was decreased by W. inflatus, unaffected by SDM-54 and T. harzianum, and increased by P. farinosus. Gliocladium roseumdecreased root length colonized when plants were 12 wk old, and T. pseudokoningii increased colonization of roots when plants were 4 wk old. Antagonistic, synergistic and neutral actions of G. mosseae upon the saprophytic fungi were observed. The population of T. harzianum decreased and the populations of T. pseudokoningii and SDM54 increased in the presence of G. mosseae. Our results indicate a complex interaction between G. mosseae and associated saprophytic fungi.