ABSTRACT
ABSTRACT The interaction between plants and pathogens is a very dynamic and complex relationship that also includes a high degree of specificity, and it is precisely this last characteristic which triggers such important responses in the survival of one or the other. The pathosystem formed by tomato (Solanum lycopersicum L.) and Fusarium oxysporum f. sp. lycopersici (Fol) has been the subject of multiple studies due to the importance of the vegetable worldwide and for the economic and ecological impact of the fungus responsible for the vascular wilt disease in tomato, causing losses that go up to 100%. One way to find alternatives for the management of any pathosystem is to know the actors involved and the mechanisms that govern the interaction through technological and scientific advances that clearly show how the interaction develops on a genetic level. This review collects the information from different scientific sources with focus on the knowledge of the fungus, tomato cultivation and plant defense applied to this pathosystem, as well as the molecular mechanisms.
RESUMEN La interacción entre plantas y patógenos es una relación muy dinámica y compleja, que conlleva un alto grado de especificidad y es esta última característica, la que desencadena respuestas tan importantes en la supervivencia de uno u otro. El patosistema formado por tomate (Solanum lycopersicum L.) y Fusarium oxysporum f. sp. lycopersici (Fol) ha sido objeto de múltiples estudios, debido a la importancia de la hortaliza, a nivel mundial y por el impacto económico y ecológico del hongo, responsable de la marchitez vascular, provocando pérdidas que llegan hasta el 100%. Una forma de encontrar alternativas para el manejo de cualquier patosistema es conocer los actores involucrados y los mecanismos que rigen la interacción, a través de avances tecnológicos y científicos, que muestren, claramente, cómo se desarrolla la interacción, a nivel genético. Esta revisión recoge la información de fuentes científicas con énfasis en el conocimiento del hongo, el cultivo del tomate y la defensa vegetal, aplicada a este patosistema, así como los mecanismos moleculares.
ABSTRACT
ABSTRACT: Colombia is the fourth largest avocado producer globally and the third largest in terms of harvested area, with a 6% share of the world area. The development and promotion of this production line represents an important source of growth in agriculture for Colombia, due to the generation of rural employment, equitable development across the different regions of the country, and due to the diversity of thermal floors and the different varieties planted. Imports of this product have decreased by 96% in the last four years from 3128 tons in 2014 to 133 tons in 2017. In recent years, the projects developed in the Colombian avocado sector have been aimed at the foreign market due to the profitability and demand of the Hass variety of this fruit. In addition, there is a state effort to implement plans for regions free of quarantine pests that allow access to foreign markets. This constitutes a strategic proposal made up of a coherent set of objectives, strategies and programmes which, based on a vision of the future, seek the initial goal of doubling the area of production. That move would ensure the technological and innovative conditions for sustainable and quality production, as well as achieve full links in international markets. This review aimed to know the main developments of avocado production in Colombia, its challenges and opportunities for the next decade.
RESUMO: A Colômbia é o quarto produtor e o terceiro em termos de área colhida, com uma participação de 6% da área mundial. O desenvolvimento e a promoção desta linha produtiva representam para a Colômbia uma importante fonte de crescimento na agricultura, para a geração de emprego e desenvolvimento rural com equidade para as diferentes regiões do país, devido à diversidade de pisos térmicos e às diferentes variedades plantadas. As importações deste produto diminuíram 96% nos últimos quatro anos, passando de 3128 toneladas em 2014 para 133 toneladas em 2017. Nos últimos anos, os projetos desenvolvidos no setor de abacate colombiano têm como objetivo o mercado externo devido à lucratividade desta fruta por sua demanda com a variedade Hass. Além disso, há um esforço estatal para implementar planos para regiões livres de pragas de quarentena que permitem o acesso a mercados estrangeiros. Dessa forma, constitui uma proposta estratégica composta por um conjunto coerente de objetivos, estratégias e programas que, com base em uma visão de futuro, buscam o objetivo inicial de duplicar a área de produção, garantindo condições tecnológicas e de inovação com alcance total nos mercados internacionais. Esta revisão tem como objetivo conhecer os principais desenvolvimentos da produção de abacate na Colômbia, seus desafios e oportunidades para a próxima década.
ABSTRACT
ABSTRACT Use of biotechnological potential of native microorganisms as bio-inputs is having a great impact on agricultural systems. Plant Growth Promoting Rhizobacteria (PGPR), in addition to their beneficial effect on plant growth and on the availability of soil elements, also have an antagonistic effect against different pathogens. In this study, growth promotion mechanisms with emphasis on the antagonism of PGPR isolated from sugarcane and tomato crops were evaluated. Antagonism against Fusarium oxysporum f.sp lycopersici (Fol) was determined by dual tests, inhibition of germination and production of chitinases and endoglucanases. 52 isolates were evaluated and according to their results in dual tests 10 were selected for further analysis. Isolate GIBI127 showed the best percentage of Inhibition Germination (IG) of Fol (59.29%). Then, a selection index was calculated using results from gi, dual tests and growth promotion mechanisms to select five best isolates. Finally, these bacteria were evaluated for chitinases and endoglucanases production using Miller's method. As a result, strain GIBI419 (Burkholderia cepacia) showed a higher production of these enzymes. Selected isolates have antagonistic potential along with plant growth promotion characteristics, which can be used for the development of microbial inoculants which allow the establishment of agricultural systems for tomato cultivation that are sustainable, efficient, and environmentally friendly.
RESUMEN El uso del potencial biotecnológico de microorganismos nativos como bioinsumos está teniendo un gran impacto en los sistemas agrícolas. Las rizobacterias promotoras del crecimiento vegetal (PGPR), además de su efecto benéfico en el crecimiento de las plantas y de facilitar la disponibilidad de elementos del suelo, también tienen un efecto antagónico frente a diferentes patógenos. En este estudio se evaluaron mecanismos de promoción del crecimiento con énfasis en el antagonismo de bacterias PGPR aisladas de cultivos de caña de azúcar y tomate. El antagonismo contra Fusarium oxysporum f.sp lycopersici (Fol) se determinó mediante pruebas duales, inhibición de la germinación y producción de quitinasas y endoglucanasas. Se evaluaron 52 aislamientos y según sus resultados en pruebas duales se seleccionaron 10 para su posterior análisis. El aislado GIBI127 mostró el mejor porcentaje de Inhibición de la Germinación (IG) de Fol (59,29%). Luego, se calculó un índice de selección utilizando los resultados de IG, pruebas duales y mecanismos de promoción del crecimiento para seleccionar los cinco mejores aislamientos. Finalmente, estas bacterias fueron evaluadas en la producción de quitinasas y endoglucanasas utilizando el método de Miller. Como resultado, se evidenció la cepa GIBI419 (Burkholderia cepacia) como la de mayor producción de estas enzimas. Los aislados seleccionados tienen un potencial antagónico junto con características de promoción del crecimiento de las plantas, que pueden usarse para el desarrollo de inoculantes microbianos que permitan el establecimiento de sistemas agrícolas para el cultivo de tomate que sean sostenibles, eficientes y amigables con el medio ambiente.