Bacterias promotoras del crecimiento en tomate con efecto antagónico sobre Fusarium oxysporum f. sp. lycopersici

Abstract

Tomato (Solanum lycopersicum L.) is one of the most consumed vegetables worldwide, with significant economic value and relevance in the world. Tomato is affected by various factors that impact on production and yield, and fungal pathogens are relevant. Vascular wilt, caused mainly by Fusarium oxysporum f. sp. lycopersici (Fol), leads to economic losses due to reductions in yield (up to 45%). Control of the pathogen is achieved through the use of resistant varieties and agrochemicals; alternative strategy for managing the disease. The main objective of this work was to search for antagonists to Fol using in vitro interactions with the pathogen, followed by the evaluation of several enzymatic production capacities, volatile compounds, and plant growth promotion. Twenty-five strains with highly competitive ability against two races of this phytopathogen were selected, as they inhibited its growth under in vitro conditions. Enzymatic activities for cellulase, glucanase, amylase, protease production, and phosphate solubilization were confirmed, as well as the production of volatiles that reduced Fol growth. In UCO 19 variety plants, the selected strains improved the variables height, stem diameter, fresh weight, and dry weight of tomato. These results are very promising for developing a bioproduct for the protection of tomato crops against Fol. however, their effectiveness is not always very effective. Additionally, there is a need to implement more environmentally friendly practices, and biological control is an alternative strategy for managing the disease. The main objective of this work was to search for antagonists to Fol using in vitro interactions with the pathogen, followed by the evaluation of several enzymatic production capacities, volatile compounds, and plant growth promotion. Twenty-five strains with highly competitive ability against two races of this phytopathogen were selected, as they inhibited its growth under in vitro conditions. Enzymatic activities for cellulase, glucanase, amylase, protease production, and phosphate solubilization were confirmed, as well as the production of volatiles that reduced Fol growth. In UCO 19 variety plants, the selected strains improved the variables height, stem diameter, fresh weight, and dry weight of tomato. These results are very promising for developing a bioproduct for the protection of tomato crops against Fol.El tomate (Solanum lycopersicum L.) es una de las hortalizas más consumidas a nivel mundial, de gran valor económico y de relevancia en el mundo. El cultivo de tomate es afectado por diversos factores que afectan la producción y el rendimiento, entre éstos, son relevantes los patógenos fúngicos. La marchitez vascular es causada principalmente por Fusarium oxysporum f. sp. lycopersici (Fol), que causa pérdidas económicas por mermas en el rendimiento (hasta 45%). El control del patógeno se realiza mediante el uso de variedades resistentes y el control químico, pero su efectividad a veces no es óptima; sumado a la necesidad de implementar prácticas más amigables con el medio ambiente, el control biológico se propone como estrategia alternativa para el control de la enfermedad. El objetivo principal del trabajo es la búsqueda de antagonistas a Fol utilizando interacción in vitro con el patógeno para luego evaluar la capacidad de producción de diversas enzimas, compuestos volátiles y promoción del crecimiento de plantas. Se seleccionaron 25 cepas con alta capacidad competitiva frente a dos razas de este fitopatógeno, al impedirle su crecimiento in vitro. Se comprobaron actividades enzimáticas de producción de celulasa, glucanasa, amilasa, proteasa y solubilización de fosfatos, además de la producción de volátiles que redujeron el crecimiento de Fol. En plantas de tomate variedad UCO 19, los antagonistas mejoraron las variables altura, diámetro del tallo, peso fresco y seco. Estos resultados son muy promisorios para desarrollar un bioinsumo para la protección del cultivo de tomate contra Fol.