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dc.contributor.advisorChavarría-Carvajal, José A.
dc.contributor.authorGarcía-Peña, José M.
dc.date.accessioned2018-11-17T21:49:02Z
dc.date.available2018-11-17T21:49:02Z
dc.date.issued2009
dc.identifier.urihttps://hdl.handle.net/20.500.11801/1354
dc.description.abstractThe use of entomopathogenic nematodes (EPN) to control insect pests in the soil is a common practice. The objectives of this investigation were to characterize the communities of EPN associated with citrus cultivation, identify the species of fungi with antagonistic potential against soil nematodes associated with citrus, and evaluate the susceptibility of Diaprepes abbreviatus to native Rhabditis spp. nematodes and the introduced EPNs Steinernema glaseri (NJ93 isolate) and Heterorhabditis bacteriophora. Samples were collected twice from five citrus orchards at the Agricultural Experiment Stations in Isabela and Adjuntas. The first was conducted from September to November 2007 and the second from April to May 2008. Nematode extraction was performed using Galleria mellonella larvae. Fungi isolation from the soil was achieved by performing serial dilutions up to 10-3. A one ml aliquot of the dilution was then placed on Rose Bengal Streptomyacin Agar. The fungal colonies were counted and expressed as log10 ufc/g of dry soil. To evaluate the susceptibility of D. abbreviatus to the EPNs and to the Rhabditis spp., D. abbreviatus larvae were inoculated with 10 IJ/cm2 of soil of each nematode species in sterile soil. For the combined treatments half of the dose was used; water was used for control. Mortality was evaluated at 2, 5 and 10 days. In none of the sampled soils were EPNs observed, but nematodes in the genus Rhabdita were consistently isolated from cadavers that had been exposed to collected soil samples. The fungi most frequently isolated and identified were: Aspergillus niger, Chaetomium globosum, Fusarium solani, Fusarium oxiporum, Gliocladium catenulatum, Paecilomyces spp., Penicillium spp., Trichoderma viride and Verticillium spp. There was no interaction between Rhabditis spp. and the EPNs. H. bacteriophora and S. glaseri (NJ93 isolate). H. Bacteriophora showed the greatest efficacy in the control of D. abbreviatus.
dc.description.abstractEl uso de nemátodos entomopatógenos (NEP) para el control de insectos plaga en el suelo es una práctica común. El presente estudio tiene como objetivos, caracterizar las comunidades de NEP asociadas a los cítricas, caracterizar las especies de hongos con potencial antagónico de nemátodos asociadas a suelos de cítricas y evaluar la susceptibilidad de Diaprepes abbreviatus al nematodo nativo Rhabditis sp. y NEP introducidos Steinerna glaseri (Aislado NJ93) y Heterorhabditis bacteriophora. Se llevaron a cabo dos muestreos en cinco huertos de cítricos en las estaciones experimentales agrícolas de Isabela y Adjuntas. El primer muestreo fue realizado de septiembre a noviembre de 2007 y el segundo muestreo de abril a mayo de 2008. La extracción de nemátodos se realizó utilizando larvas de Galleria mellonella. Para aislar los hongos del suelo se realizaron diluciones seriadas hasta 10-3, de esta se sembró una alícuota de 1 ml en Agar Rosa de Bengala con Estreptomicina. Se contabilizaron las colonias de hongos y se expresaron como log10 ufc/g suelo seco. Para evaluar la susceptibilidad de D. abbreviatus a los NEP y a Rhabditis spp., se utilizaron larvas de este insecto y se inocularon con 10 IJ/cm2 de suelo de cada una de las especies de nematodos en suelo estéril. Para los tratamientos combinados se utilizó la mitad de la dosis, como control se aplicó agua. Se evalúo la mortalidad a los 2, 5 y 10 días. En ninguno de los predios muestreados se observo la presencia de NEP, pero si la presencia constante de un nemátodo del género Rhabditis (Rhabditoidea) en las larvas muertas. Los hongos aislados e identificados más frequentemente fueron: Aspergillus niger, Chaetomium globosum, Fusarium solani, Fusarium oxiporum, Gliocladium catenulatum, Paecilomyces spp., Penicillium spp., Trichoderma viride y Verticillium spp. No se observó interacción entre Rhabditis spp. y los NEPs. H. bacteriophora y S. glaseri (aislado NJ93). H. bacteriophora mostró mayor eficiencia en el control de D. abbreviatus.
dc.description.sponsorshipProyecto Z-TSTART-41: Habitat and Role of Natural Enemies in Regulating Spatial Patterns of Entomopathogenic Nematodesen_US
dc.language.isoesen_US
dc.subjectCultivo de cítricosen_US
dc.subjectHongosen_US
dc.titleNemátodos entomopatógenos y hongos del suelo con potencial antagónico a nemátodos entomopatógenos asociados a cítricasen_US
dc.typeThesisen_US
dc.rights.licenseAll rights reserveden_US
dc.rights.holder(C) 2009 José Miguel García Peñaen_US
dc.contributor.committeeRivera Vargas, Lydia I.
dc.contributor.committeeJenkins, David
dc.contributor.representativeCafaro, Matías
thesis.degree.levelM.S.en_US
thesis.degree.disciplineCrop Protectionen_US
dc.contributor.collegeCollege of Agricultural Sciencesen_US
dc.contributor.departmentDepartment of Crops and Agro-Environmental Sciencesen_US
dc.description.graduationYear2009en_US


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