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Our objective was to evaluate the biomass production and partitioning of Festuca arundinacea (tall fescue) plants infected with endophyte Epichloë coenophiala and inoculated with arbuscular mycorrhizal fungi (HMA) in response to phosphate fertilization (P). For this, an experiment was carried out in pots in a growth chamber, through a completely randomized design with a factorial arrangement with 5 repetitions. The growth of F. arundinacea was evaluated in presence or not of E. coenophiala (SE- and SE+, respectively), inoculated with HMA (HMA+ and HMA-, with and without inoculation, respectively) and fertilized with phosphorus (P15 and P0, with and without fertilization, respectively). After 160 days of growth, the total fresh biomass (TFB) and its partitioning into aboveground (AFB) and belowground (BFB), and air dry weight (ADW) were quantified. Mycorrhizal colonization was quantified in roots. HMA+ plants showed lower BFT, BFA and BFR than HMA- plants in SE- and P0 conditions. No differences in BFT and PSA were detected between HMA+ and HMA- plants at P15. At P0, HMA- plants showed higher PFA than HMA+ plants. SE- plants showed higher PSA than SE+ plants. In SE+ plants inoculated with HMA for the P0 condition, abundant extraradical mycelium was recorded, although there was no evidence of interradical colonization or formation of arbuscules or vesicles. At P15, extraradical mycelium was observed around the roots (which were shorter than the roots of unfertilized plants) in only one sample of SE-. Under the conditions of the present experiment, expected responses in biomass production in plants infected with the endophyte fungus and inoculation with HMA and synergism between both symbionts were not recorded. Furthermore, no modulating effect of phosphate fertilization on the expected responses was found. [ABSTRACT FROM AUTHOR]

Copyright of Lilloa is the property of Fundacion Miguel Lillo and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The aim of this work was to characterize cultural, morphological, physiological and molecular endospore forming endophytic bacteria associated with Theobroma cacao L. in Quinindé canton, Esmeraldas province, Ecuador. Isolation of bacteria was done from healthy pods and flower pedicels from cocoa Criollo Type Nacional cultivar. Bacteria isolates were characterized cultural, morphological, physiological and molecular. Identification of bacteria isolates were analyzed by 16S-ribosomal RNA gene pyrosequencing. Fourty-five endospore forming endophytic bacteria were recovered from healthy pods and flowers peduncules, mainly from endocarp. Based on their cultural, morphological and physiological characteristics they were similar to Bacillus. According to 16S rDNA sequence alignment isolates were classified like Bacillus subtilis, Bacillus amyloliquefaciens, Bacillus mycoides and Bacillus cereus with 99 % sequence similarity. Some bacteria isolates did not produced optimal concensus sequences and were classified under the genus Bacillus. [ABSTRACT FROM AUTHOR]

The aim of this work was to determine the antifungal activity of Bacillus subtilis 9-2, Bacillus mycoides 29-2, Bacillus sp. 33 and 72, Bacillus cereus 45-1, 51-2, 53-4 and Bacillus amyloliquefaciens 24 on mycelial growth and sporulation of the phytopathogenic fungus Moniliophthora roreri H.C Evans et al. The confrontation experiments were carried out in Petri dishes with two compartments. PDA culture medium was added to one side of the plate and TSA to the other. The bacterial strains were individually inoculated (100 µl; 1×108 CFU ml-1) on the face of the cap with TSA culture medium; while on the other lid with PDA culture medium, a mycelial disk (5 mm in diameter) of the strain of the phytopathogenic fungus was placed. Sterile distilled water was used as a control. All plates were sealed with Parafilm and incubated at 28°C for 15 days. The experiments were repeated twice. All strains of bacteria produced volatile compounds that inhibited mycelial growth and the formation of M. roreri spores. B. subtilis 9-2, B. mycoides 29-2, B. sp. 33, Bacillus cereus 45-1, 51-2 and Bacillus amyloliquefaciens 24 inhibited mycelial growth and sporulation of M. roreri by more than 60%. These findings offer new possibilities to control frosty pod rot caused by M. roreri using Bacillus endophytes strains producing antifungal volatile compounds. [ABSTRACT FROM AUTHOR]

Genus Vaccinium groups plants like shrubs that grows in the highlands of the Andes Mountains. Its fruits are characterized by their antioxidant and nutritional properties. The objective of this paper review was to understand the effect of endophytic and associated microorganisms with the rhizosphere of Vaccinium spp. Wild Vacciunium species present low genetic variability, in comparison with cultivated species that present high variability. Therefore, wild species must be domesticated in order to achieve permanent production in various locations along the year. Domestication of this plant could be achieved by stablishing physiological plant system, determining its edaphoclimatic requirements and analysis of interactions with the plant. One of the main problems of the Vaccinium genus is fungal diseases, such as Botrytis sp. and Hemileia vastatrix. However, other endophytic and rhizosphere microorganisms interact positively with Vaccinium plants: providing mineral nutrients, offering protection against diseases, and even improving soil structure. The diversity of microbiome associated with the plant rhizosphere and the genetic diversity of Vaccinium floribundum are relevant aspects that should be studied to stablish genetic improvement programs and achieve the commercial cropping of the species. [ABSTRACT FROM AUTHOR]

Copyright of Biomédica: Revista del Instituto Nacional de Salud is the property of Instituto Nacional de Salud of Colombia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Introduction: Infectious diseases are the main cause of deaths in the world, antimicrobial resistance is a global problem, and therefore, research of new sources of potentially effective antimicrobial agents, of natural origin is convenient. Objective: To evaluate the antimicrobial activity of endophytic fungi of M. americana and M. oleifera in S. aureus (ATCC® 29213 ™), S. aureus (resistant strain USb003), E. coli (ATCC® 25922 ™) and E. coli (resistant strain USb007). 25922 ™). Materials and methods: Endophytic fungi, leaves, seeds and stems of the two plants under study were isolated. Their antimicrobial activity was evaluated through the formation of sensitivity haloes by dual tests in vitro and through tests with crude ethanolic extracts from the endophytes, to which they were evaluated minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC). and cytotoxicity. Results: Three ethanolic extracts of Penicillium sp., Cladosporium (001) and Cladosporium (002), showed greater inhibition halos in sensitive and resistant strains of E. coli and S. aureus. The MIC, CBM found, were statistically significant (P≤0.05), compared with the control of gentamicin, the cytotoxicity tests CC50> 1000 showed that endophytic fungi have bactericidal characteristics without causing any damage. Conclusion: There is a source of active secondary metabolites with antimicrobial and non-toxic properties in the endophytic fungi of M. oleifera and M. americana; these findings are important to continue with chemical identification of the compounds, and research on the mechanisms of action, highlighting that the isolation of endophytes in these plants is scarce or unknown. [ABSTRACT FROM AUTHOR]

The endophytic and stimulating effect of four strains of Trichoderma asperellum Samuels, Lieckfeldt & Nirenberg (Ta. 13, Ta. 78, Ta. 85, and Ta. 90) on Phaseolus vulgaris (Cv. BAT-304) was evaluated under semi-controlled conditions. The number of leaves and roots, plant height, root length, fresh foliar and root mass, dry foliar and root mass, endophytic capacity in roots, foliar content of N, P, K and the induction of peroxidase enzymes (POD), polyphenoloxidases (PPO), and phenylalanine ammonium lyases (PAL) were determined. The evaluations were carried out in 15-day old plants sown at two times:1) plant sowing and soil inoculation with Trichoderma at the same time, 2) planting seven days after soil inoculation with the fungus). The strain Ta. 85 produced the greatest stimulation in terms of number of leaves, plant height and root length with the first time of sowing. All the strains were endophytic for the bean cultivar studied. Ta. 90 and Ta.85 increased the leaf content of N with the first sowing time, whereas Ta. 78, Ta. 85, and Ta. 90 did it with the second sowing time. Only Ta. 78 increased the leaf K with respect to the control with the second sowing time. The plants treated with Ta. 78 showed higher POD, PPO and PAL enzymatic activities with respect to the control plants. Ta. 13 increased POD and PPO activities, whereas Ta. 85 and Ta. 90 only the PPO activity. The results suggest that strain Ta. 85 inoculated at bean planting is efficient in stimulating growth, whereas Ta. 78 stood out in nutrition and induction of possible resistance in this crop. [ABSTRACT FROM AUTHOR]

Azospirillum brasilense is a nitrogen-fixing plant growth promoting rhizobacterium with potential as biofertiliser for leguminous and non-leguminous plants. Agriculturally important crops, especially sugar cane, have been often inoculated with A. brasilense producing increases in growth parameters and yield in different soils and climatic regions. Sugar cane inoculated with A. brasilense has been grown in intercropping with legumes like beans and soybean. In field experiments of intercropping of sugarcane inoculated with A. brasilense and soybean carried out in Cuban soils, an increase in most of the growth parameters of sugarcane have been observed, but it is not known the effects produced on the other intercropped plant. This work analyzes the alterations in plant and nodule development, nitrogenase activity and colonization of roots by Azospirillum, in soybean inoculated with A. brasilense 8-INICA and Bradyrhizobium japonicum USDA-110. A. brasilense inoculation did not produced changes in the height and biomass of aerial parts of the plant or in nitrogenase activity in nodules. However increases in root and nodule biomass were detected with its inoculation. A. brasilense colonized root surface by adhesion to mucilaginous material where bacteria proliferate and are able to form microcolonies inside. The break caused by the emergence of a secondary root allowed the bacterium to enter in the intercellular spaces of plant root parenchyma and between epidermal root cells, allowing soybean root colonization. These results suggested that A. brasilense 8-INICA can live as an endophyte in soybean roots and could be a suitable candidate like inoculant of leguminous with agricultural purposes. [ABSTRACT FROM AUTHOR]

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El presente trabajo se realizó con el objetivo de actualizar el estado de información existente sobre los microorganismos endófitos asociados a Theobroma cacao L. como agentes de control biológico de la moniliasis, causada por Moniliophthora roreri Evans et al. Se resume sobre el origen y evolución de las definiciones de microorganismos endófitos, enfatizando en el control biológico de las enfermedades del cacao con énfasis en la moniliasis, uno de los problemas fitosanitarios de mayor importancia a nivel mundial; así como se hace una valoración sobre sus perspectivas de empleo. Los hongos y bacterias endófitos presentan varios mecanismos de acción entre los que se encuentran: competencia directa por el espacio y nutrientes, antibiosis, micoparasitismo, resistencia sistémica inducida y promoción del crecimiento; funciones que son parte de las estrategias para el manejo eficaz y sostenible de la moniliasis. The present work was carried out with the objective of updating the state of existing information on the endophytic microorganisms associated with Theobroma cacao L., as agents of biological control of moniliasis, caused by Moniliophthora roreri Evans et al. It is summarized on the origin and evolution of the definitions of endophytic microorganisms, emphasizing the biological control of cocoa diseases with emphasis on moniliasis, one of the most important phytosanitary problems worldwide; as well as an assessment of their employment prospects. Fungal and bacterial endophytes have several mechanisms of action, which include direct competition for space and nutrients, antibiosis, mycoparasitism, induced systemic resistance and promotion of growth; functions that are part of the strategies for an effective and sustainable management of the frosty pod rot. [ABSTRACT FROM AUTHOR]

Gluconacetobacter diazotrophicus is an endophyte microorganism with direct and indirect mechanisms for vegetable growth promotion among its characteristics. Despite its great perspective to constitute the active principle of a bioproduct for agricultural purposes, so far there is not any product derived from this bacterial species in Cuba. The strain isolation and its characterization are important steps to obtain a biopreparation, since it enables the initial selection of strains with adequate characteristics for vegetable growth stimulation. In this research, 85 endophyte isolates were purified from different organs of 24 plant species. Four of them were identified as Gluconacetobacter diazotrophicus, when comparing its characteristics with those from pattern strains of the bacterial species. Microorganisms were selected from mango (Mangifera indica L.) and guava (Psidium guajava L.) fruits as well as from yucca (Manihot esculenta Crantz.) and beet (Beta vulgaris L.) stems. The presence of this microorganism was relevant in the first two crops for Cuba whereas the isolation in guava at the international level. The four strains had differences regarding their capacity to solubilize phosphorus, to produce indol acetic acid and its antagonistic activity against Fusarium moniliforme and Fusarium incarnatum. As strains were grouped according to their characteristics, mango and beet microorganisms were different, which are considered promising to study the effect of its interaction with other crops under in vivo conditions. [ABSTRACT FROM AUTHOR]

During 2010/2011 and 2011/2012 in tobacco crop seasons, a research was carried out at the Tobacco Experimental Station of San Juan y Martínez, Pinar del Río, Cuba, with the objective of determining the economic feasibility of two microbial inoculant methods applied to dark tobacco crop in the sun. A random block was designed with 19 treatments and four repetitions. Different mineral fertilizer rates were studied combined with two microbial inoculants (Azotobacter chroococcum and Bacillus megatherium var. phosphaticum). Two variants were employed: an inoculation at sowing time of the seedbeds and another which included the initial inoculation plus a reinoculation at transplanting time. Better results were achieved by reinoculation and mineral fertilizer reduction than by inoculation method. The economic feasibility of A. chroococcum + B. megatherium var. phosphaticum reinoculation plus 75 % of total nitrogen and phosphorus rates was proved in dark tobacco cultivated at the sun. [ABSTRACT FROM AUTHOR]

Copyright of Universitas Scientiarum is the property of Pontificia Universidad Javeriana and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this work, endophytic fungi from leaves and pods of bean presenting anthracnose symptoms were isolated from plants collected at different municipalities in the province of Antioquia (Colombia). Isolates were identified by sequencing the rDNA ITS regions together with the examination of reproductive structures during sporulation in culture media. Colletotrichum lindemuthianum, the causal agent of anthracnose was isolated in all samples showing symptoms of this disease. These results were confirmed by duplex PCR using the specific primers CD1/CD2 and CY1/CY2. Additionally, 17 endophytic fungi were obtained. Fourteen isolates did not sporulate in culture media (Mycelia sterilia) but were identified by phylogenetic analysis of the ITS regions as the Ascomycetes: Leptosphaerulina (3), Diaporthe (3), Gibberella (1), Plectosphaerella (1) and Biscogniauxia (1) and the mitosporic genera Phoma (2), Alternaria (2) and Stemphylium (1). Three isolates were identified combining morphological and molecular analysis as Fusarium (2) and Curvularia lunata (1). This work increases our knowledge of the mycobiota of legume plants and will serve as support of future studies aimed at determining the effect of these fungi on the development of anthracnose as well as other problems affecting the bean crop. [ABSTRACT FROM AUTHOR]

The present study objective was to determine the population diversity of endophytic bacteria associated to different tissues of rice varieties and their antimicrobial activity against Burkholderia glumae. The population diversity of culturable endophytic bacteria was performed by isolation morphotypes from tissues superficially disinfected four commercial rice varieties, was conducted in R2A, population density (CFU/gof tissue)was estimated by direct counting R2A medium colonies. The presence of total non-endophytic bacteria culturable bacteria was performed by extraction of DNA and subsequent amplification of 16S rDNA gene using universal primers for eubacteria. The antibacterial activity of endophytic bacteria on B.glumae was made by the technique of diffusion on the surface of culture media with discs. The statistical differences between culturable endophytic bacteria according to variety, tissue ANOVA were performed, parametric and non-parametric test using the program R. A total of 89 morphotypes of endophytic bacteria were isolated with greater presence F733 and Fmocari varieties associated to root, stem and leaf in greater proportion. The electrophoretic profiles hows the presence of endophytic bacteria in roots, stem and leaves of the varieties Fmocari and F733. Antibacterial in vitro test shows that endophytic bacteria have inhibitory activity on B. glumae. This is the first report to date has been in Colombia on the inhibitory effect of endophytic bacteria on the causal agent of bacterial panicle blight in rice. [ABSTRACT FROM AUTHOR]

In recent years, the international scientific community has an increasing interest for the endophytic bacterium Gluconacetobacter diazotrophicus, an atmospheric nitrogen-fixing microorganism, which is also a producer of crop growth-promoting substances. Therefore, taking into account its agrobiologic potential and the scarce studies about the effect that may provoke the application of products manufactured through the effective strain fermentation, this investigation was laid out, with the aim of selecting an effective strain of Gluconacetobacter diazotrophicus to promote tropical vegetable growth, development and yield, such as sweet potato (Ipomea batatas Lam.), cassava (Manihot esculenta, Crantz) and taro (Xanthosoma spp.), cultivated on a Red Ferralitic soil. INIFAT Abn1, isolated from sweet potato crop, was the most promising strain to increase all indicators in the three crops, with higher promoting values between 23 and 46 %. The significance of having a wide diversity collection to perform an adequate selection was proved, as well as the non-existence of a direct relationship of crop origin-strain effectiveness. [ABSTRACT FROM AUTHOR]

This study aims to determine the effect of endophytic bacterial isolates on the development of sorghum (Sorghum bicolor (L.) Moench) var. UDG 110. By means of an experiment under controlled conditions could elucidate the effect of isolates on crop growth parameters and plant biomass. The results demonstrated that from 37 isolates, 8 of them were selected due to the best results upon the evaluations, which were compared among them and with the control treatment to determine the statistical differences on growth parameters and plants biomass. Several endophytes were able to stimulate the root length, the fresh and dry shoot and roots weight, resulting the most relevant the isolates the 5, 8 (isolated at 7 days), 22 (isolated at 60 days) and 36 (isolated from the seeds). These results demonstrate the effectiveness of the implementation of endophytic microorganisms to achieve increases in growth parameters of this important grain and for the further production of inoculants based on efficient native strains. [ABSTRACT FROM AUTHOR]

Copyright of Agro Sur is the property of Universidad Austral de Chile, Facultad de Ciencias Agrarias and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In recent years, the study of endophytic plantmicroorganism associations has grown special interest, emphasizing on the introduction of good agrobiological results into agricultural practice. This work shows an outlook of the current and prospect situation of these associations mostly illustrated by Rhizobium-cereal, Azorhizobium-rice, Azospirillum and Herbaspirillum interactions, as well as cereals and Gluconacetobacter diazotrophicus with different crops. There is a microbial rotation process with Rhizobium bacteria at different cyclical association phases of the agroecosystem (legume, nodule-soil-grass-soil-legume) in relation to productivity physiology and yield. Concerning the study with G. diazotrophicus, on certain tropical vegetable and fruit determinations under Cuban conditions, a cell concentration of 4.2x105 per gram of fresh tissue was recorded in inoculated plants whereas 2.7x102 cells per gram of fresh tissue in non-inoculated ones (control); therefore, it is necessary to increase bacterial concentration, both under experimental and field conditions, to obtain an adequate answer of agrobiological effect on the above mentioned species. The answer of casaba, dasheen and papaya to inoculation constitutes a first world report. There was a great economic impact of inoculation with a higher benefit/cost ratio than 40:1; thus, it is an extremely attractive biotechnology to be introduced into the current agrobiological market. Besides, the result has a scientific, technological, environmental and social impact. [ABSTRACT FROM AUTHOR]

Removing bacteria from seed surface is one of the main issues when identifying endophytic bacteria as well as with microorganism-inoculating trials. Disinfection by chemical methods has been a commonly used strategy with this goal. However, it is very hard to fully disinfect rice seeds, due to its particular characteristics (rough and velvety surface), so that most disinfection methods described by literature are often useless. Therefore, this investigation was aimed at searching an efficient rice seed disinfection methodology. Then, seeds from cv. J-104 were used and four disinfection protocols were assessed by employing different disinfecting solutions (chloramine T, calcium hypochlorite and alcohol, among others), exposure times and solution combination. Results showed that by disinfection protocol 4, using calcium hypochlorite in two plant growth stages, the best germination and disinfection rates were achieved, obtaining an efficient disinfection method, which could be applied to plant- microorganism interaction studies, from the practical point of view. [ABSTRACT FROM AUTHOR]

Gluconacetobacter diazotrophicus is an endophyte of sugarcane that produces high quantities of fixed nitrogen and plant growth regulating substances. These capacities are very important for the improvement of sugarcane crop. In this work, the interactions between this species and endophytic microbial community members were demonstrated. Different interactions are present in the microbial endophytic community. Gluconacetobacter diazotrophicus inhibits the growth of some species and it is also stimulated by others. These relationships are influenced by their strain and growth time. The relationships between Gluconacetobacter diazotrophicus and other members of the microbial endophytic community could contribute to enhance their effect on this important graminaceous crop. [ABSTRACT FROM AUTHOR]