Effect of management (ecological and conventional) on functional groups of soil microorganisms in coffee agroecosystems with different resilience to climate variability, Colombia

The effect of management (ecological and conventional) on functional groups of microorganisms of soil in agroecosystems with different resilience scores reported to climate variability in Anolaima, Colombia was evaluated. Were found clustering associated with management and cellulolytic bacteria and fungi abundances. No differences found in diversity of phosphate solubilizing or nitrogen-fixing microorganisms, related to management. The diversity of microbial functional groups was affected by the climatic condition of sampling season. Management was relevant in relationships between resilience scores to climate variability and cellulolytic microorganisms; in ecological agroecosystems, biodiversity knowledge, agroecological main structure, and the participation of farmers in organizations were important.

Assessment of cellulolytic microorganisms in soils of Nevados Park, Colombia

A systematized survey was conducted to find soil-borne microbes that degrade cellulose in soils from unique ecosystems, such as the Superpáramo, Páramo, and the High Andean Forest in the Nevados National Natural Park (NNNP), Colombia. These high mountain ecosystems represent extreme environments, such as high levels of solar radiation, low atmospheric pressure, and extreme daily changes in temperature. Cellulolytic activity of the microorganisms was evaluated using qualitative tests, such as growth in selective media followed by staining with congo red and iodine, and quantitative tests to determine the activity of endoglucanase, β-glucosidase, exoglucanase, and total cellulase. Microorganisms were identified using molecular markers, such as the 16S rRNA gene for bacteria and the internal transcribed spacer region (ITS) of ribosomal DNA for fungi. Multivariate statistical analysis (MVA) was used to select microorganisms with high cellulolytic capacity. A total of 108 microorganisms were isolated from the soils and, in general, the enzymatic activities of fungi were higher than those of bacteria. Our results also found that none of the organisms studied were able to degrade all the components of the cellulose and it is therefore suggested that a combination of bacteria and/or fungi with various enzymatic activities be used to obtain high total cellulolytic activity. This study gives an overview of the potential microorganism that could be used for cellulose degradation in various biotechnological applications and for sustainable agricultural waste treatment.