ABSTRACT Introduction: In Colombia, panela is an ancestral food obtained by concentration from the extraction of sugarcane juice. Arbuscular Mycorrhizal Fungi (AMF) help the exchange and mobility of nutrients by associating with plants, improving quality and yield in different production systems. Objective: To evaluate the effect of AMF inoculation in sugarcane cultivation on panela yield and quality. Materials and Methods: The study was carried out in Suaita, Santander, under a randomized complete block design, in triplicate with four treatments (T1: Acaulospora mellea, T2: Rhizophagus irregularis, T3: control 50% and T4: control 100% fertilization). The variables in sugarcane were maturity indexes and tons per hectare, and in panela yield, tons per hectare, conversion to panela, reducing sugars, total solids, pH, moisture, sucrose, and soluble phosphorus were determined. Results and Discussion: There were significant differences (P>0.05) in the maturity index with T2 and a higher content of reducing sugars in panela with T1, in the other variables, a benefit of the inoculation with respect to the controls was observed, being T2 the treatment with the highest values in production of stems.ha-1, tons of cane.ha-1; and T1 in conversion to panela, reducing sugars, soluble phosphorus and total solids. Conclusions: Interaction of R. irregularis and A. mellea with panela quality and yield was found, obtaining promising results for the use of these microorganisms to enhance the sustainability and competitiveness of sugarcane for panela.

RESUMEN Introducción: En Colombia la panela es un alimento ancestral obtenido por concentración a partir de extracción de jugos de la caña azucarera. Los Hongos Formadores de Micorrizas Arbusculares (HFMA) ayudan al intercambio y movilidad de nutrientes al asociarse con plantas, mejorando la calidad y rendimiento en diferentes sistemas productivos. Objetivo: Evaluar el efecto de la inoculación con HFMA en el cultivo de la caña de azúcar sobre el rendimiento y la calidad en panela. Materiales y Métodos: El estudio se desarrolló en Suaita, Santander, bajo un diseño de bloques completos al azar, por triplicado con cuatro tratamientos (T1: Acaulospora mellea, T2: Rhizophagus irregularis, T3: Control 50% y T4: Control 100% de fertilización). Las variables en caña fueron índices de madurez y toneladas por hectárea, y en panela se determinaron rendimiento, toneladas por hectárea, conversión a panela, azúcares reductores, sólidos totales, pH, humedad, sacarosa y fósforo soluble. Resultados y Discusión: Se presentaron diferencias significativas (P>0,05) en el índice de madurez con el T2 y mayor contenido de azúcares reductores en panela con el T1, en las demás variables se observó un beneficio de la inoculación respecto los controles, siendo T2 el tratamiento con valores altos en producción de tallos.ha-1, toneladas caña.ha-1; y T1 en conversión a panela, azúcares reductores, fósforo soluble y sólidos totales. Conclusiones: Se encontró interacción de R. irregularis y A. mellea con la calidad y rendimiento en panela, obteniéndose resultados prometedores del uso de estos microorganismos para potencializar la sostenibilidad y competitividad de la caña azucarera para panela.

Abstract The aim of this study was to standardize a diagnosis procedure to detect Mycobacterium avium subsp. paratuberculosis (Map) DNA in raw cow milk samples under field conditions. A procedure that combines both immunomagnetic separation and IS900 -PCR detection (IMS-IS1 PCR) was employed on milk samples from 265 lactating Holstein cows from Map infected and uninfected herds in Argentina. IMS-IS1 PCR results were analyzed and compared with those obtained from milk and fecal culture and serum ELISA. The extent of agreement between both tests was determined by the Kappa test. IMS-IS1 PCR showed a detection limit of 101 CFU of Map/mL of milk, when 50:50 mix of monoclonal and polyclonal antibodies were used to coat magnetic beads. All of the 118 samples from the Map uninfected herds were negative for the set of the tests. In Map infected herds, 80 out of 147 cows tested positive by milk IMS-IS1 PCR (55%), of which 2 (1.4%) were also positive by milk culture, 15 (10%) by fecal culture, and 20 (14%) by serum ELISA. Kappa statistics (95% CI) showed a slight agreement between the different tests (<0.20), and the proportions of agreement were ≤0.55. The IMS-IS1 PCR method detected Map in milk of the cows that were not positive in other techniques. This is the first report dealing with the application of IMS-IS1 PCR in the detection of Map in raw milk samples under field conditions in Argentina.