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Chlorothalonil (CHT) is a chlorinated-nitrogen fungicide used in the control of black sigatoka, a disease that affects banana and plantain, has adverse effects on the environment and its metabolites can be toxic. The CHT has been the object of several studies related to its behavior and degradation in the environment; however, few works have been developed in tropical areas, such as the case of the banana zone of Magdalena - Colombia. In addition, it is unknown if the microbial diversity existing in these soils can transform compounds such as CHT, thus these microorganisms can be the basis for the implementation of remediation strategies based on bioaugmentation. In this sense, the present study aims to evaluate the degradation of CHT in soils of a tropical coastal zone, under conditions of natural attenuation and bioaugmentation with native microorganisms. For this purpose, microorganisms capable of growing with CHT as their sole carbon source (10.8 mg.L-1) and tolerating a concentration up to 25 mg.L-1 were isolated and selected from soils in the Magdalena-Colombia banana zone. Subsequently, CHT degradation tests (2000 ng.g-1) were performed on experimental plots, with bioaugmentation of native microorganisms and natural attenuation during 35 days, evaluating the growth of microbial populations and the degradation of CHT by gas chromatography associated with a mass spectrometry detector (GC/MS). Because of the microbial selection process, 8 morphotypes were obtained with the ability to grow in CHT as the sole carbon source and tolerate concentrations up to 25 g.L-1. The isolates were identified by sequencing the 16S rDNA gene as belonging to the genera Enterobacter, Klebsiella, Pseudomonas and Citrobacter. The CHT degradation tests showed that under bioaugmentation conditions with the native microorganisms selected in the study, a 100% reduction was achieved after 21 days; while under natural attenuation conditions after 35 days the degradation reached values of 9

ONTARE. REVISTA DE INVESTIGACIÓN DE LA FACULTAD DE INGENIERÍA For the urban canopy of the EAN University, harnessed to monitor pollinated and growing plants, a bioprospection of the nitrogen cycle microorganisms in five soil samples was conducted. Fifteen mesophilic aerobic morphotypes were selected, from which six are nitrogen fixers and do not produce any lesions on the Lactuca sativa leaves, used as a biological model to show potential pathogens for plants. Diazotrophs isolation in urban canopy demonstrates its potential utilization as the future formulation of biofertilizers that could be applied in both, the EAN University and other green roofs., La Canopée Urbaine de l’Université EAN est mise à profit pour le suivi de polinisateurs et la culture de plantes mais aussi pour la réalisation de bioprospection de micro-organismes participant au cycle de l’azote dans cinq échantillons de sol. Sur les quinze morphotypes d’aérobies mésophiles qui ont été sélectionnés, six sont fixateurs d’azote et ne produisent pas de lésions aux feuilles de Lactuca sativa, plante utilisée comme modèle biologique pour mettre en évidence de possibles agents végétaux pathogènes. L’isolement de diazotrophes au sein de la Canopée Urbaine révèle une potentielle profitabilité via la création future de bio-engrais appliqués aux toits végétaux urbains., Aproveitado para monitorar as plantas polinizadas e cultivadas no canopy urbano da Universidade EAN, se realizou em cinco amostras de solo a bioprospecção de microrganismos do ciclo de nitrogênio. Foram selecionados 15 morfótipos mesófilos aeróbios, dos quais seis são fixadores de nitrogênio e não produzem lesões nas folhas de Lactuca sativa, usadas como modelo biológico para evidenciar possíveis patógenos para as plantas. O isolamento de diazotróficas no Canopy Urbano demonstra seu potencial aproveitamento a formulação a futuro de bio-fertilizantes que sejam aplicados tanto na Universidade EAN como em outros telhados verdes., ONTARE. REVISTA DE INVESTIGACIÓN DE LA FACULTAD DE INGENIERÍA Para el Canopy Urbano de la Universidad EAN, aprovechado para el seguimiento de polinizados y cultivo de plantas, se realizó la bioprospección de microorganismos del ciclo de nitrógeno en cinco muestras de suelo. Se seleccionaron 15 morfotipos aerobios mesófilos, de los cuales seis son fijadores de nitrógeno y no producen lesiones en hojas de Lactuca sativa, usado como modelo biológico para evidenciar posibles patógenos para plantas. El aislamiento de diazotrofos en el Canopy Urbano demuestra su potencialidad de aprovechamiento como la formulación a futuro de biofertilizantes que sean aplicados, tanto en la Universidad EAN como en otros techos verdes.