Endófitos bacterianos y su potencial en biotecnología agrícola: el caso de pseudomonas fluorescens PICF7 (original) (raw)
Endophytic Bacteria; Diversity, Characterization and Role in Agriculture
Entophytic bacteria have an important role in the growth process and health of the plant host. Nevertheless, also some endophytic bacteria are existing in seeds and have not been studied yet. In addition, some Entophytic bacteria are important in plant tolerance to environmental stresses. They can colonize the internal tissues of the host and are able to use a variety of different relations including symbiotic, mutualism, communalistic, and trophobiotic. They have the ability for plant hormone production like auxin, indole acetic acid, and gibberellin; also some endophytic bacteria have the ability for siderophore creation, phosphate solubilization, nitrogen fixation, protease, and hydrogen cyanide formation.. Moreover, they produce compounds that could have possible usage in drug, agriculture or engineering. They have the ability to removesoil toxins thus, improving phytoremediation and soil fertility. Further, most of endophytic bacteria are diazotrophs and associated with the Proteobacteria, and a varied range has been detected agreeing to the nifH gene which codes for nitrogenase enzyme, structures recovered from plant materials, however a limited part of these genes looks to be stated. The endophytes discussed in this review are isolated from surface-disinfested plant tissue, and that do not damage the plant. Moreover, endophytes appear to be in-between saprophytic bacteria and plant pathogens, they are either saprophytes growing to be pathogens, or extremely grown plant pathogens with protective accommodation and nutrient provisions, but not killing their host. Generally, endophytic bacteria are partial under biotic and abiotic influences, with the plant itself being one of the main prompting influences.
Bacterial endophytes in agricultural crops
Canadian Journal of Microbiology, 1997
Abstract: Endophytic bacteria are ubiquitous in most plant species, residing latently or actively colonizing plant tissues locally as well as systemically. Several definitions have been proposed for endophytic bacteria; in this review endophytes will be defined as those bacteria that ...
Effects of Endophytic Bacteria on Disease and Growth in Plants under Biotic Stress
Yüzüncü Yıl Üniversitesi Tarım Bilimleri Dergisi, 2018
The aim of this study was to reveal the effects of four endophytic bacteria (EB) (Ochrobactrumsp. CB36/1, Pantoea agglomerans CC37/2, Bacillus thuringiensis CA41/1 and Pseudomonas fluorescens CC44) on the plant development of tomato and pepper and the effects against bacterial spot disease caused by Xanthomonas euvesicatoria (Xe) in both hosts. EB applied on tomato and pepper seedlings cultivated in a sterile peat growing medium in a climate chamber in two different periods to the roots. The pathogen inoculated on the leaves by spraying. Disease severity was measured by different scales for tomatoes and peppers, and plant development parameters were determined at the end of the study. The antagonistic effects of EB against Xe and 1-Aminocyclopropane-1-carboxylic acid (ACC) deaminase activities were determined with in vitro studies. The effect of endophytic bacteria on tomato and pepper varied according to the host plant x endophyte x pathogen combination. While no bacteria were effe...
Impact of Endophytic Microorganisms on Plants, Environment and Humans
The Scientific World Journal, 2014
Endophytes are microorganisms (bacteria or fungi or actinomycetes) that dwell within robust plant tissues by having a symbiotic association. They are ubiquitously associated with almost all plants studied till date. Some commonly found endophytes are those belonging to the generaEnterobacter sp.,Colletotrichum sp.,Phomopsis sp.,Phyllosticta sp.,Cladosporium sp.,and so forth. Endophytic population is greatly affected by climatic conditions and location where the host plant grows. They produce a wide range of compounds useful for plants for their growth, protection to environmental conditions, and sustainability, in favour of a good dwelling place within the hosts. They protect plants from herbivory by producing certain compounds which will prevent animals from further grazing on the same plant and sometimes act as biocontrol agents. A large amount of bioactive compounds produced by them not only are useful for plants but also are of economical importance to humans. They serve as anti...
Bacterial Endophyte Colonization and Distribution within Plants
Microorganisms
The plant endosphere contains a diverse group of microbial communities. There is general consensus that these microbial communities make significant contributions to plant health. Both recently adopted genomic approaches and classical microbiology techniques continue to develop the science of plant-microbe interactions. Endophytes are microbial symbionts residing within the plant for the majority of their life cycle without any detrimental impact to the host plant. The use of these natural symbionts offers an opportunity to maximize crop productivity while reducing the environmental impacts of agriculture. Endophytes promote plant growth through nitrogen fixation, phytohormone production, nutrient acquisition, and by conferring tolerance to abiotic and biotic stresses. Colonization by endophytes is crucial for providing these benefits to the host plant. Endophytic colonization refers to the entry, growth and multiplication of endophyte populations within the host plant. Lately, plant microbiome research has gained considerable attention but the mechanism allowing plants to recruit endophytes is largely unknown. This review summarizes currently available knowledge about endophytic colonization by bacteria in various plant species, and specifically discusses the colonization of maize plants by Populus endophytes.
Interaction between bacterial endophytes and host plants
Frontiers in Plant Science
Endophytic bacteria are mainly present in the plant’s root systems. Endophytic bacteria improve plant health and are sometimes necessary to fight against adverse conditions. There is an increasing trend for the use of bacterial endophytes as bio-fertilizers. However, new challenges are also arising regarding the management of these newly discovered bacterial endophytes. Plant growth-promoting bacterial endophytes exist in a wide host range as part of their microbiome, and are proven to exhibit positive effects on plant growth. Endophytic bacterial communities within plant hosts are dynamic and affected by abiotic/biotic factors such as soil conditions, geographical distribution, climate, plant species, and plant-microbe interaction at a large scale. Therefore, there is a need to evaluate the mechanism of bacterial endophytes’ interaction with plants under field conditions before their application. Bacterial endophytes have both beneficial and harmful impacts on plants but the exact ...
Bacterial endophytes and their interactions with hosts
Molecular Plant-Microbe …, 2006
Recent molecular studies on endophytic bacterial diversity have revealed a large richness of species. Endophytes promote plant growth and yield, suppress pathogens, may help to remove contaminants, solubilize phosphate, or contribute assimilable nitrogen to plants. Some endophytes are seedborne, but others have mechanisms to colonize the plants that are being studied. Bacterial mutants unable to produce secreted proteins are impaired in the colonization process. Plant genes expressed in the presence of endophytes provide clues as to the effects of endophytes in plants. Molecular analysis showed that plant defense responses limit bacterial populations inside plants. Some human pathogens, such as Salmonella spp., have been found as endophytes, and these bacteria are not removed by disinfection procedures that eliminate superficially occurring bacteria. Delivery of endophytes to the environment or agricultural fields should be carefully evaluated to avoid introducing pathogens.
Revista Industrial Y Agricola De Tucuman, 2013
RESUMEN Efecto del residuo agrícola de la cosecha en verde de la caña de azúcar en el desarrollo de microorganismos de importancia agrícola y ambiental En la actualidad, la industria azucarera mundial tiende a reemplazar la quema del cañaveral previo a la cosecha, por el sistema de caña verde. Trabajos demuestran que cuando el residuo agrícola de cosecha (RAC) regresa al suelo, aporta nutrientes, materia orgánica y mejora su estructura. Sin embargo, el efecto del RAC en el desarrollo de microorganismos del suelo aún no ha sido evaluado en Tucumán, R. Argentina. Por esta razón, el objetivo de este trabajo fue evaluar los cambios que ocurren en el desarrollo de microorganismos de importancia agrícola y ambiental, en dos situaciones de manejo del suelo: con y sin mantenimiento de cobertura con RAC. Los ensayos se realizaron en el Dpto. Leales, Tucumán, utilizando la variedad LCP 85-384 en la edad de soca 4; es decir, los tratamientos se establecieron cuatro años antes del muestreo. Para el análisis microbiológico, se tomaron muestras de suelo y de diferentes tejidos durante los meses de junio, julio, noviembre 2011 y mayo 2012. El recuento de microorganismos se realizó utilizando diferentes medios de cultivo: LB para aerobios mesófilos totales, APG para hongos y levaduras, AC para Pseudomonas sp. y medios de cultivo semisólidos libres de N2 para bacterias microaeróbicas fijadoras de nitrógeno. En forma general, se observó que la cobertura con RAC aumentó el número de hongos, levaduras y Pseudomonas sp. durante las épocas con temperaturas más altas. Algunos hongos presentaron actividad ligninolítica y algunas Pseudomonas sp. fueron capaces de solubilizar fósforo, lo que indica que estos microorganismos podrían estar involucrados en la descomposición del residuo. Fue interesante observar que la cobertura con RAC también incrementó el número de bacterias fijadoras de nitrógeno asociadas a raíces y tallos, de junio a febrero. El mayor desarrollo de microorganismos degradadores de materia orgánica y una mejor colonización de los tejidos por bacterias fijadoras de nitrógeno podrían mejorar el crecimiento y desarrollo del cañaveral.