Evaluación de bacterias fijadoras de nitrógeno en suelos del bosque seco tropical del departamento del Atlántico
Cargando...
Fecha
2019
Autores
Castro Álvarez, Maria Fernanda
Martínez Castaño, Maria Alicia Esther
Título de la revista
ISSN de la revista
Título del volumen
Editor
Ediciones Universidad Simón Bolívar
Facultad Ciencias Básicas y Biomédicas
Facultad Ciencias Básicas y Biomédicas
Resumen
Antecedentes: El bosque seco tropical (BST) es uno de los ecosistemas más alterados en el mundo. Este se ha reducido debido al aumento de tierras agropecuarias, mineras y urbanas; generando una alteración del paisaje y en la microbiota del suelo. Por lo cual, es necesario determinar el estado de las comunidades microbianas existentes; especialmente promotores del crecimiento vegetal, que puedan implementarse en su recuperación. Materiales y Métodos: Se evaluó la diversidad de bacterias fijadoras del nitrógeno de suelos naturales e intervenidos del BST del departamento del Atlántico. Para ello, se aislaron bacterias y se comparó la diversidad. Los aislados fueron caracterizados macro y microscópicamente, se evaluó su capacidad para fijar nitrógeno, la presencia de genes de involucrados en este metabolismo; y el potencial solubilizador de fosfato. Paralelamente, se hizo análisis fisicoquímico y respiración basal de estos suelos. Por último, identificaron genes relacionados a estos metabolismos. Resultados: Se observó mayor diversidad en el suelo natural que en el intervenido. Se obtuvieron seis aislados diferentes, con capacidad fijadora de nitrógeno y dos de ellos son solubilizadores de fosfato. Estos últimos mostraron crecimiento rápido, y se determinó que potencialmente no son patogénicos. Conclusión: La intervención del BST afecta negativamente la diversidad bacteriana del suelo, incluyendo microorganismos promotores del crecimiento vegetal. En consecuencia, la pérdida de las comunidades microbianas del suelo debe afectar la capacidad de recuperación del bosque. Los aislados obtenidos, potencialmente podrán ser usados como inoculantes para restaurar el BST; así como en el desarrollo de la agricultura sostenible en la región.
Introduction: The tropical dry forest (BST) is one of the most altered ecosystems in the world. This has been reduced due to the increase in agricultural, mining and urban lands; generating an alteration of the landscape and in the soil microbiota. Therefore, it is necessary to determine the status of existing microbial communities; especially plant growth promoters, which can be implemented in their recovery. Materials and Methods: The diversity of nitrogen fixing bacteria of natural and intervened soils of the BST of the Atlantic department was evaluated. To do this, bacteria were isolated and diversity was compared. The isolates were characterized macro and microscopically, their ability to fix nitrogen was evaluated, the presence of genes involved in this metabolism; and the phosphate solubilizer potential. In parallel, physicochemical analysis and basal respiration of these soils were made. Finally, they identified genes related to these metabolisms. Results: Greater diversity was observed in the natural soil than in the intervention. Six different isolates were obtained, with nitrogen fixing capacity and two of them are phosphate solubilizers. The latter showed rapid growth, and it was determined that they are potentially not pathogenic. Conclusion: The BST intervention negatively affects the bacterial diversity of the soil, including plant growth promoting microorganisms. Consequently, the loss of soil microbial communities should affect the resilience of the forest. The isolates obtained can potentially be used as inoculants to restore the BST; as well as in the development of sustainable agriculture in the region.
Introduction: The tropical dry forest (BST) is one of the most altered ecosystems in the world. This has been reduced due to the increase in agricultural, mining and urban lands; generating an alteration of the landscape and in the soil microbiota. Therefore, it is necessary to determine the status of existing microbial communities; especially plant growth promoters, which can be implemented in their recovery. Materials and Methods: The diversity of nitrogen fixing bacteria of natural and intervened soils of the BST of the Atlantic department was evaluated. To do this, bacteria were isolated and diversity was compared. The isolates were characterized macro and microscopically, their ability to fix nitrogen was evaluated, the presence of genes involved in this metabolism; and the phosphate solubilizer potential. In parallel, physicochemical analysis and basal respiration of these soils were made. Finally, they identified genes related to these metabolisms. Results: Greater diversity was observed in the natural soil than in the intervention. Six different isolates were obtained, with nitrogen fixing capacity and two of them are phosphate solubilizers. The latter showed rapid growth, and it was determined that they are potentially not pathogenic. Conclusion: The BST intervention negatively affects the bacterial diversity of the soil, including plant growth promoting microorganisms. Consequently, the loss of soil microbial communities should affect the resilience of the forest. The isolates obtained can potentially be used as inoculants to restore the BST; as well as in the development of sustainable agriculture in the region.
Descripción
Palabras clave
Abundancia, Bosque seco tropical, Diversidad, Fijadores de nitrógeno, Solubilización de fosfato, Promotores del crecimiento vegetal, Abundance, Tropical dry forest, Diversity, Nitrogen fixers, Phosphate solubilization, Plant growth promoters