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dc.contributor.advisorEstévez-de Jensen, Consuelo
dc.contributor.authorVega-Jiménez, Byron P.
dc.date.accessioned2018-11-17T21:45:07Z
dc.date.available2018-11-17T21:45:07Z
dc.date.issued2009
dc.identifier.urihttps://hdl.handle.net/20.500.11801/1348
dc.description.abstractNatural infection of American soybean rust, caused by Phakopsora meibomiae Arthur, was studied during 2006 to 2008 in experimental plots established at Isabela, Adjuntas and Juana Díaz Agriculture Experiment Stations of the University of Puerto Rico. The American soybean rust was observed on Lablab purpureus and Phaseolus lunatus in Adjuntas from June to October, 2007. Soybean rust identification was carried out by DNA analysis using PCR of the ITS region of the rDNA. In order to observe natural infections on wild hosts, different surveys were conducted in fourteen municipalities of the island. Twenty nine percent of the samples were positive for P. meibomiae. L. purpureus presented the highest disease severity. Additionally, P. meibomaie was found in Vigna luteola, Macroptilium lathyroides, Pachyrhizus erosus, P. lunatus and Vigna sp. Thirty eight percent of infected legumes were observed between 501 and 600 meters. Two different rust lesions were observed: a tan color reaction with abundant sporulation, and a reddish brown lesion with reduced sporulation. Lesion size on L. purpureus varied from 0.92-0.60 to 0.68- 0.41 mm. Average number of uredinium per cm2 was 31.6, with an average of 118.77 urediniospores/uredinium. Uredinium patterns and the release of the urediniospores were observed in scanning electron microscopy. Aditionally, host range studies were conducted in 15 legumes. Canavalia gladiata, Crotalaria brevidens, Mucuna pruriens and Pueraria phaseoloides had immune reaction. The shortest incubation and latent periods were observed on P. vulgaris with 3.23 and 6.27 days, respectively. The greatest number of uredinium per individual lesion was observed on P. vulgaris with an average of 5.79. During the two years of survey, the presence of Asian soybean rust caused by P.pachyrhizi, was never observed nor identified.
dc.description.abstractEn lotes experimentales de soya en las Estaciones Experimentales de Isabela, Adjuntas y Juana Díaz, se determinó la infección natural de la roya americana de la soya, causado por Phakopsora meibomiae Arthur, en 2006 a 2008. La roya americana se presentó únicamente en Adjuntas, en Lablab purpureus y Phaseolus lunatus, en siembras contiguas, durante la siembra de Junio a Octubre del 2007. La identificación de la especie fue realizada mediante análisis de ADN, utilizando PCR y secuenciación de la región ITS del rADN. Se realizaron monitoreos en catorce municipios de la isla para determinar la infección natural en hospederos silvestres. El 29% de muestras resultaron positivas, siendo L. purpureus la de mayor prevalesencia. Adicionalmente, se reportó presencia de P. meibomiae en Vigna luteola, Macroptilium lathyroides, Pachyrhizus erosus, P. lunatus y Vigna sp. El 38% de las muestras infectadas se presentó entre los 501 y 600 metros. Las reacciones observadas fueron de tipo TAN (lesiones bronceadas con abundante esporulación) y RB (lesiones caférojizas y poca esporulación). En L. purpureus, el tamaño de las lesiones variaron de 0.92- 0.60 mm por 0.68-0.41 mm. El número promedio de uredos por cm2 fue de 31.6, con un promedio de 118.77 uredosporas/uredo. La estructura de los uredos y los patrones de liberación de uredosporas se observaron mediante microscopía electrónica de rastreo. Para determinar el rango de hospederos se evaluaron 15 especies de leguminosas. Canavalia gladiata, Crotalaria brevidens, Mucuna pruriens y Pueraria phaseoloides fueron inmunes. El período de incubación y de latencia más corto se observó en P. vulgaris con 3.23 y 6.27 días, respectivamente. El mayor número de uredos por lesión individual lo produjo P. vulgaris con un promedio de 5.79. Durante los dos años de monitoreo, no se observó ni se identificó la presencia de la roya asiática de la soya, causada por P. pachyrhizi.
dc.description.sponsorshipProyecto T-STAR-ZTS-31en_US
dc.language.isoesen_US
dc.subjectLablab purpureusen_US
dc.subjectPhaseolus lunatusen_US
dc.subjectRoya americanaen_US
dc.titleEtiología de la Roya americana de la soya, Phakopsora meibomiae Arthur, en Puerto Ricoen_US
dc.typeThesisen_US
dc.rights.licenseAll rights reserveden_US
dc.rights.holder(C) 2009 Byron Patricio Vega Jiménezen_US
dc.contributor.committeeRivera, Lydia
dc.contributor.committeeBeaver, James
dc.contributor.representativeOrellana, Linette
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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