ABSTRACT
This study aimed to develop and validate a standard area diagram (SAD) set to estimate the severity of bacterial blight of eucalyptus caused by Erwinia psidii. For this purpose, an eight-level SAD was developed and validated by ten inexperienced raters. Accuracy and precision of the estimates by each rater, with and without the SAD, were determined based on Lin's concordance correlation coefficient. The proposed SAD improved the accuracy and precision of the estimates. The SAD set studied here is a useful tool in assessments of bacterial blight of eucalyptus for epidemiological research and breeding programs.(AU)
Este trabalho objetivou o desenvolvimento de uma escala para estimar a severidade da seca-de-ponteiros do eucalipto causada por Erwinia psidii. Para isso, uma escala de oito níveis foi desenvolvida e validada por dez avaliadores inexperientes. A acurácia e precisão das estimativas de cada avaliador, com e sem a escala, foram determinadas baseadas no coeficiente de correlação concordante de Lin. A escala proposta melhorou a acurácia e a precisão das estimativas. A escala estudada se mostrou uma ferramenta útil na avaliação da seca-de-ponteiros do eucalipto para estudos epidemiológicos e em programas de melhoramento.(AU)
Subject(s)
Plant Diseases/microbiology , Bacterial Infections/classification , Erwinia , Eucalyptus/microbiology , Reproducibility of ResultsABSTRACT
Abstract Plant growth-promoting rhizobacteria strains from special formulations have been used to optimize eucalyptus cutting production. To undertake quality control for the formulated products, the rhizobacterial strains should be characterized to assess their purity and authentication. In the present study, we characterized nine strains of rhizobacteria, including three Bacillus subtilis (S1, S2 and 3918), two Pseudomonas sp. (MF4 and FL2), P. putida (MF2), P. fulva (Ca), Frateuria aurantia (R1), and Stenotrophomonas maltophilia (CIIb). The strains were differentiated by colony morphology after 24 h of incubation in three different solid state culture media (glucose-nutritive agar, 523 medium and yeast extract-mannitol agar), sensitivity to a panel of 28 antibiotics (expressed according to the formation of inhibition halos of bacterial growth in the presence of antibiotics), and PCR-RFLP profiles of the 16S rDNA gene produced using nine restriction enzymes. It was possible to differentiate all nine strains of rhizobacteria using their morphological characteristics and sensitivity to antibiotics. The molecular analysis allowed us to separate the strains CIIb, FL2 and R1 from the strains belonging to the genera Bacillus and Pseudomonas. By using these three methods concomitantly, we were able to determine strain purity and perform the authentication.
Subject(s)
Bacteria , Eucalyptus/growth & development , Eucalyptus/microbiology , Rhizosphere , Bacteria/classification , Bacteria/growth & development , Bacteria/drug effects , Bacteria/genetics , Polymorphism, Restriction Fragment Length , RNA, Ribosomal, 16S/genetics , Microbial Sensitivity Tests , Anti-Bacterial Agents/pharmacologyABSTRACT
Introducción: la criptocococis es una micosis sistémica causada por C. neoformans y C. gattii, es frecuente y oportunista en inmunocomprometidos y patógeno primario en personas inmunocompetentes. C. neoformans tiene una distribución mundial y se ha aislado desde las excretas de palomas. C. gattii se considera restringida a regiones con clima tropical, subtropical, y templadas, se encuentra asociada frecuentemente a detritos de especies de Eucalyptus sp. La virulencia de estas levaduras le permite desarrollar patogénesis en mamíferos y supervivencia en el ambiente. Objetivo: Identificar y determinar la actividad de proteinasas y fosfolipasas, de C. neoformans y C. gattii aisladas desde las oquedades de árboles en lugares con alta afluencia de público. Materiales y Métodos: Se tomaron 200 muestras de hisopado desde distintas especies de árboles desde sectores de la región de OHiggins y el Maule. Se siembran en ASG, se aíslan y mantienen en ASD. Identificación con tinta china, Urea de Christensen, crecimiento a 37°C, asimilación y fermentación de azucares, y siembra en medio CGB. Se mide índice de actividad enzimática Prz de proteinasas y fofolipasas. Resultados y Conclusiones: Se obtuvieron 109 cepas de C. neoformans aisladas desde las oquedades de diferentes especies arbóreas y 3 cepas presuntivas de C. gattii desde Eucalyptus sp. y Prunus cerasifera artropurpurea. El 88,1 por ciento de las cepas C. neoformans y 100 por ciento de C. gattii, presentaron alta actividad proteolítica, El 49,5 por ciento de las cepas de C. neoformans y 33,3 por ciento de C. gattii mostraron alta actividad de fosfolipasas.
Introduction: criptocococis is a systemic mycosis caused by C. neoformans and C. gattii, frequent and opportunistic in immunocompromised and primary pathogen in immunocompetent persons. C. neoformans has a worldwide distribution and has been isolated from the excreta of pigeons. C. gattii is considered restricted to regions with tropical, subtropical, and temperate, is often associated with species of Eucalyptus sp. The virulence of these yeasts develop pathogenesis allows survival in mammals and the environment. Objective: To identify and determine the activity of proteinases and phospholipases of C. neoformans and C. gattii isolated from the hollows of trees in places with high turnout. Materials and Methods: 200 swab samples were taken from different species of trees from areas of the region of OHiggins and Maule. Planted in ASG, they are isolated and kept in ASD. Identification with ink, Urea Christensen, growth at 37 ° C, assimilation and fermentation of sugars, and planting medium CGB. Prz index proteinase enzyme activity is measured and phospholipases. Results and Conclusions: We manage to get 109 strains of C. neoformans isolated from the hollows of different tree species and 3 presumptive strains of C. gattii from Eucalyptus sp. and Prunus cerasifera artropurpurea. 88.1 percent of the strains C. neoformans and C. gattii 100 percent , they showed high proteolytic activity, 49.5 percent of the strains of C. neoformans and C. gattii 33.3 percent showed high activity phospholipases.
Subject(s)
Humans , Cryptococcus gattii/isolation & purification , Cryptococcus gattii/enzymology , Cryptococcus gattii/pathogenicity , Cryptococcus neoformans/isolation & purification , Cryptococcus neoformans/enzymology , Cryptococcus neoformans/pathogenicity , Peptide Hydrolases , Phospholipases , Trees/microbiology , Chile , Cryptococcosis/etiology , Eucalyptus/microbiology , Lung Diseases, Fungal , Prunus/microbiologyABSTRACT
Se aislaron bacterias rizosféricas y endófitas a partir de rizósfera y tejidos de raíz de árboles de Eucalyptus nitens con el objetivo de evaluar su capacidad de promover el crecimiento en plántulas de la misma especie en condiciones de invernadero. Los aislamientos que incrementaron el crecimiento de las plántulas fueron identificados y caracterizados por su capacidad de producir ácido indolacético (AIA), solubilizar fosfato y expresar la 1-aminociclopropano-1-carboxilato (ACC) desaminasa. Los 105 aislamientos obtenidos fueron morfológicamente diferentes y solo 15 promovieron significativamente el crecimiento de plántulas de E. nitens. Los máximos incrementos observados fueron en el peso seco aéreo (142 %) y de la raíz (135 %); también aumentaron la altura de las plantas (50 %) y el largo de raíces (45 %) de las mismas. Las rizobacterias pertenecieron a los géneros Arthrobacter, Lysinibacillus, Rahnella y Bacillus. Los aislados identificados como A. phenanthrenivorans 21 y B. cereus 113 incrementaron la emergencia de E. nitens a los 12 días en un valor promedio de 3,15 veces con relación al control. R. aquatilis aislado 78 presentó la mayor producción de AIA (97,5 ± 2,87 μg/ml) en presencia de triptófano y el mayor índice de solubilización de fósforo (2,4). B. amyloliquefaciens aislado 60 fue positivo para la actividad ACC desaminasa. Los resultados obtenidos indican el potencial de las rizobacterias estudiadas como promotoras de emergencia y crecimiento de plántulas de E. nitens y su posible uso como inoculantes, ya que presentan más de un mecanismo de acción asociado a la promoción del crecimiento.
Rhizospheric and endophytic bacteria were isolated from the rizosphere and root tissue of Eucalyptus nitens. The objective of this work was to evaluate their capacity to promote growth in seedlings of the same species under greenhouse conditions. The isolates that improved seedling growth were identified and characterized by their capacity to produce indoleacetic acid (IAA), solubilize phosphates and increase 1-aminocyclopropane-1-carboxylate (ACC) deaminase activity. One hundred and five morphologically different strains were isolated, 15 of which promoted E. nitens seedling growth, significantly increasing the height (50%), root length (45%) as well as the aerial and root dry weight (142% and 135% respectively) of the plants. Bacteria belonged to the genus Arthrobacter, Lysinibacillus, Rahnella and Bacillus. Isolates A. phenanthrenivorans 21 and B. cereus 113 improved 3.15 times the emergence of E. nitens after 12 days, compared to control samples. Among isolated R. aquatilis, 78 showed the highest production of IAA (97.5±2.87 μg/ml) in the presence of tryptophan and the highest solubilizer index (2.4) for phosphorus, while B. amyloliquefaciens 60 isolate was positive for ACC deaminase activity. Our results reveal the potential of the studied rhizobacteria as promoters of emergence and seedling growth of E. nitens, and their possible use as PGPR inoculants, since they have more than one mechanism associated with plant growth promotion.
Subject(s)
Eucalyptus/microbiology , Rhizobium/isolation & purification , Rhizobium/physiology , Seedlings/growth & development , Seedlings/microbiology , Plant Roots/microbiologyABSTRACT
Trichoderma spp is the cause of the green mold disease in mushroom cultivation production. Many disinfection treatments are commonly applied to lignocellulose substrates to prevent contamination. Mushroom growers are usually worried about the contaminations that may occur after these treatments during handling or spawning. The aim of this paper is to estimate the growth of the green mold Trichoderma sp on lignocellulose substrates after different disinfection treatments to know which of them is more effective to avoid contamination during spawning phase. Three different treatments were assayed: sterilization (121 ºC), immersion in hot water (60 and 80 ºC), and immersion in alkalinized water. Wheat straw, wheat seeds and Eucalyptus or Populus sawdust were used separately as substrates. After the disinfection treatments, bagged substrates were sprayed with 3 mL of suspension of conidia of Trichoderma sp (10(5) conidia/mL) and then separately spawned with Pleurotus ostreatus or Gymnopilus pampeanus. The growth of Trichoderma sp was evaluated based on a qualitative scale. Trichoderma sp could not grow on non-sterilized substrates. Immersions in hot water treatments and immersion in alkalinized water were also unfavorable treatments for its growth. Co- cultivation with mushrooms favored Trichoderma sp growth. Mushroom cultivation disinfection treatments of lignocellulose substrates influence on the growth of Trichoderma sp when contaminations occur during spawning phase. The immersion in hot water at 60 ºC for 30 min or in alkalinized water for 36 h, are treatments which better reduced the contaminations with Trichoderma sp during spawning phase for the cultivation of lignicolous species.
Subject(s)
Agaricales/growth & development , Disinfection/methods , Trichoderma/growth & development , Alkalies/metabolism , Anti-Infective Agents/metabolism , Eucalyptus/microbiology , Hot Temperature , Populus/microbiology , Temperature , Trichoderma/drug effects , Trichoderma/radiation effects , Triticum/microbiologyABSTRACT
Eucalypts is one of the main species used for commercial reforestation in the state of Rio Grande do Sul, Brazil. This study aimed to evaluate the survival and early growth of eucalyptus trees in an area subject to sandy process after three years of growth. The Eucalyptus grandis seedlings were grown in a greenhouse, innoculated or not with the isolated ectomycorrhizal Pisolithus microcarpus (UFSC-Pt116), produced in peat or Entisol. After 120 days, the seedlings were transplanted to an area subject to the sandy process, in the city of São Francisco de Assis, RS. The plants have been evaluated regarding survival, height, stem diameter, nitrogen, phosphorus and potassium levels and total phosphorus, inorganic phosphorus, organic phosphorus and wood production on different days after planting. The seedlings grown on the Entisol which was inoculated with the isolated UFSC-Pt116 presented higher survival rates, height, stem diameter, nitrogen concentration and wood production compared to the non-inoculated seedlings. Inoculation with ectomycorrhizal fungi enhanced the production of E. grandis seedlings in survival rates, height, stem diameter.
Subject(s)
Basidiomycota/growth & development , Eucalyptus/growth & development , Eucalyptus/microbiology , Mycorrhizae/growth & development , Brazil , Eucalyptus/physiology , Plant Development , Seedlings/growth & development , Seedlings/microbiology , Seedlings/physiologyABSTRACT
A circular cryptic plasmid named pPAGA (2,734 bp) was isolated from Pantoea agglomerans strain EGE6 (an endophytic bacterial isolate from eucalyptus). Sequence analysis revealed that the plasmid has a G+C content of 51 percent and contains four potential ORFs, 238(A), 250(B), 131(C), and 129(D) amino acids in length without homology to known proteins. The shuttle vector pLGM1 was constructed by combining the pPAGA plasmid with pGFPmut3.0 (which harbors a gene encoding green fluorescent protein, GFP), and the resulting construct was used to over-express GFP in E. coli and P. agglomerans cells. GFP production was used to monitor the colonization of strain EGE6gfp in various plant tissues by fluorescence microscopy. Analysis of EGE6gfp colonization showed that 14 days after inoculation, the strain occupied the inner tissue of Eucalyptus grandis roots, preferentially colonizing the xylem vessels of the host plants.
Subject(s)
Eucalyptus/microbiology , Pantoea/genetics , Plasmids , DNA, Bacterial , Green Fluorescent Proteins , Polymerase Chain Reaction , RNA, Ribosomal, 16SABSTRACT
Chrysophorte cubensis induced canker occurs in nearly all tropical and subtropical regions where eucalypts are planted, causing losses in both wood quality and volume productivity, especially so in the warmer and more humid regions of Brazil. The wide inter and intra-specific genetic variability of resistance to canker among Eucalyptus species facilitates the selection of resistant plants. In this study, we evaluated resistance to this pathogen in five Eucalyptus grandis (G) and 15 E. urophylla (U) trees, as well as in 495 individuals from 27 progenies derived from crosses between the trees. In the field, six-months-old test seedlings were inoculated with C. cubensis. Lesion length in the xylem and bark was measured eight months later. The results demonstrated that xylem lesions could preferentially be used for the selection of resistant clones. Eight trees (7 U and 1 G) were susceptible, and the remainder (8 U and 4 G) resistant. Individual narrow and broad sense heritability estimates were 17 and 81 percent, respectively, thereby suggesting that canker resistance is quantitative and highly dependent on dominance and epistasis.
Subject(s)
Eucalyptus/genetics , Fungi , Immunity, Innate , Plant Diseases/microbiology , Eucalyptus/microbiology , Genetic VariationABSTRACT
En un control fitosanitario efectuado en las provincias de San Antonio y Valparaíso, algunos árboles de plantaciones de Eucalyptus sp., presentaron un daño cortico vascular, síntomas de amarillez foliar y presencia de galerías subcorticales con compromiso medular, abundantes larvas de un coleóptero xilófago y presencia de micelio. Las muestras del tronco mantenidas en cámara de crianza por 45 días, permitieron la emergencia del estado adulto del insecto, determinándose como Ectinogonia buquetti Spinola (Coleoptera, Buprestidae). En los cultivos en cámara húmeda de la corteza afectada y del escarabajo en agar avena, se desarrolló además un hongo con abundantes peritecios negros de largos cuellos. Morfológicamente se clasificó como Ophiostoma stenoceras (Robak) Melin & Nannf., con anamorfo en Sporothrix (Ascomycota, Ophiostomatales, Ophiostomataceae), determinación ratificada por M.J. Wingfield en Sud Africa. Su fase conidial es casi indistinguible del patógeno humano Sporothrix schenckii. Actualmente se considera como un saprófito o un topatógenodébil, sin registros aparentes en Chile. Se aportan datos taxonómicos y filogenéticos actuales del complex O. stenoceras, de sus integrantes en el suelo, madera de coníferas y su asociación a coleópteros vectores.
During a phytosanitary control carried out in San Antonio and Valparaíso provinces, some trees belongingto Eucalyptus sp. plantations exhibited vascular cortical lesions, yellowish leaves signs and the existence ofsubcortical galleries involving some medular compromise together with a high number of xylophagous coleopteran larvae and presence of mycelia. Samples of the trunk which were kept in breeding chambers for 45 days allowed the emergence of the insect in its adult stage which was identified as Ectinogonia buquetti Spinola (Coleoptera, Buprestidae). In cultures of the affected bark kept in a humid chamber as well as the beetle put in oatagar, a fungus having abundant black long-necked perithecia was developed. It was morphologically classified as Ophiostoma stenoceras (Robak) Melin &Nannf, with its anamorph in Sporothrix (Ascomycota, Ophiostomatales, Ophiostomatacea), a classificationwhich was confirmed by M.J.Winfield in South Africa. Its conidial stage is almost undistinguished from the human pathogen Sporothrix schenckii. It is considered at present as a saprophyte or a weak phytopathogenous which lacksapparent records in Chile.Updated taxonomic and phylogenetic data of the O.stenoceras complex, about its components in the soil, conipherous wood as well as its association with coleopteran vector are supplied.
Subject(s)
Trees/microbiology , Coleoptera , Eucalyptus/microbiology , Fungi/isolation & purification , Fungi/classification , Fungi/pathogenicity , Insect Vectors , ChileABSTRACT
Introducción. Cryptococcus gattii serotipo B ha sido asociado con diferentes especies de árboles en regiones tropicales y subtropicales. Este serotipo es el segundo de mayor importancia clínica en Colombia, pero no se había recuperado del ambiente en ninguno de los estudios realizados por nuestro grupo. Objetivo. Para establecer la presencia y distribución de las especies del complejo C. neoformans, especialmente del serotipo B, y determinar algunas características fenotípicas relacionadas con la virulencia de los aislamientos recuperados, se diseñó un muestreo de material vegetal en un bosque de piso térmico frío del departamento de Cundinamarca. Materiales y métodos. Durante febrero y marzo de 2003 se realizaron 4 muestreos en el bosque y se tomaron 167 muestras de detritos de eucaliptos y 28 muestras de otras especies de árboles, las cuales se procesaron empleando el método convencional de extracción y siembra en medio selectivo. Se determinó el tamaño celular y capsular en los filtrados, el crecimiento a 37°C, la virulencia en un modelo animal y la pareja sexual por PCR. Resultados. Se aisló C. gattii serotipo B de 46 muestras de eucaliptos (27,5 por ciento ). El tamaño celular en el extracto estuvo entre 3,10 y 4,15 µm y el tamaño capsular entre 0,30 y 0,46 µm. Los 46 aislamientos crecieron a 37°C, pero ninguno de los dos aislamientos empleados causó la muerte de los animales inoculados durante los 70 días de observación. Todos los aislamientos fueron pareja sexual a. Conclusiones. Este estudio es el primer informe sobre el aislamiento de C. gattii, serotipo B, pareja sexual a, en Colombia a partir de detritos de eucaliptos
Subject(s)
Cryptococcus/isolation & purification , Ecosystem , Eucalyptus/microbiology , Phenotype , Birds/microbiology , FecesABSTRACT
Cryptococcus neoformans é um fungo patogênico oportunista que causa meningoencefalite como a apresentação clínica mais importante em pacientes imunocomprometidos, principalmente, em pessoas infectadas pelo HIV. O agente é uma levedura encapsulada, comumente encontrada em solo enriquecido com excretas de aves e em resíduos de plantas. O total de 290 amostras de excretas de pombos e outras aves, de árvores ornamentais e materiais vegetais de Eucalyptus foram coletadas para estudar possíveis fontes ambientais de Cryptococcus spp, na cidade de Goiânia, Goiás. A determinação das variedades, sorotipos e suscetibilidade in vitro frente a fluconazol, itraconazol e anfotericina B dos isolados de C. neoformans foram realizadas. C. neoformans var. grubii (sorotipo A) foi a única isolada, ocorrendo em 36 (20.3%) das 177 amostras fecais de pombos e em 5 (14.3%) das 35 amostras de Eucalyptus. Nenhum dos isolados ambientais de C. neoformans mostrou resistência in vitro aos três antifúngicos avaliados. O conhecimento da principal via para infecção criptocócica humana, isto é inalação de partículas infecciosas de fontes saprofíticas e a ocorrência de 60 casos de criptococose em pacientes com AIDS, em Goiânia, entre outubro de 2001 e abril de 2002, justificam o estudo de habitats do agente como prováveis fontes de criptococose nesta cidade.
Subject(s)
Animals , Humans , Antifungal Agents/pharmacology , Cryptococcus neoformans/isolation & purification , Environmental Microbiology , Brazil , Columbidae , Cryptococcus neoformans/classification , Cryptococcus neoformans/drug effects , Eucalyptus/microbiology , Feces/microbiology , Microbial Sensitivity Tests , Serotyping , Urban HealthABSTRACT
Ninety five samples of plant debris collected from November 1993 to July 1995 under the canopies of Eucalyptus camaldulensis plantation in the northeastern state of Sergipe, Brazil, were examined for yeast of the genus Cryptococcus growth. C. laurentii was repeatedly isolated from samples collected under the canopies of the trees during all the period of study. The long lasting positivity suggest colonization of these microenviroments and point to a saprobiotic natural of C. laurentii related to E. camaldulensis. Flower buds and green leaves, also examined, produced negative results. Essential oils extracted from E. camaldulensis showed ability to inhibit the growth of C. laurentii and both varieties of C. neoformans.These findings argue against the possibility of endophytic relation between these yeasts and E. camaldulensis.
Subject(s)
Cryptococcus/isolation & purification , Eucalyptus/microbiology , Cryptococcus/growth & developmentABSTRACT
O presente trabalho estuda o processo fermentativo de produçÝo de 2, 3-butanodiol, a partir de hidrolisado hemicelulósico de eucalipto, empregando a bactéria Klebsiella pneumoniae. Primeiramente foram comparados diversos tratamentos para a remoçÝo de inibidores do crescimento bacteriano presentes na matéria-prima, verificando-se a necessidade de se combinar a precipitaçÝo por variaçÝo do pH com a adsorçÝo por carvÝo ativo. Em seguida estudou-se as condiçSes de fermentaçÝo para a conduçÝo do processo em regime descontínuo alimentado em reator, o qual se mostrou mais eficiente que o regime descontínuo em frascos agitados. Finalmente avaliou-se a influência da concentraçÝo de substrato do meio de alimentaçÝo ('S IND. i') e da vazÝo de alimentaçÝo (phi), sobre a cinética do processo
Subject(s)
Eucalyptus/microbiology , Fermentation , Klebsiella pneumoniae/metabolism , BiotechnologyABSTRACT
O objetivo deste trabalho foi mostrar a aplicaçäo das metodologias estatísticas de modelagem matemática ao estudo do processo fermentativo de produçäo de proteína microbiana pelo fungo Paecilomyces variotii cultivado em hidrolisado hemicelulósico de eucalipto. Conceitos de estatística multivariada com a aplicaçäo de técnicas de planejamento fatorial fracionário foram utilizados para realizar uma triagem das variáveis que de fato säo importantes para o processo. Em seguida foi feita a quantificaçäo dos níveis das variáveis significativas do processo, mediante o emprego da metodologia de superfície de resposta. O trabalho resultou em três modelos matemáticos principais, que representam satisfatoriamente os processos envolvidos nos experimentos: a) Um modelo matemático para representaçäo do processo hidrolítico, em funçäo da concentraçäo ácida ('X IND. 2') e da temperatura ('X IND. 3'), considerando a concentraçäo ácida de 0,35 por cento de 'H IND. 2' S 'O IND. 4', dado por: Y=21,87+0,37'X IND. 3'-2,87'X POT. 2 IND. 2'-7,20'X POT. 2 IND. 3' b) Um modelo matemático para representar os nutrientes necessários, e suas concentraçöes, assim como o tempo adequado para a incubaçäo, dado pela equaçäo: Y=10,65+2,40'X POT. 1'+2,36'X POT. 2'+1,16'X POT. 1''X POT. 2'-2,10'X POT. 2 IND. 1'-1,06'X POT. 2 IND. 2', onde 'X IND. 1', representa a concentraçäo de sulfato de amônio e 'X POT. 2', o tempo de fermentaçäo. c) Um modelo matemático para representar as condiçöes de fermentaçäo ao cultivar o microorganismo em um fermentador de sete litros, em funçäo de 'X IND. 1' (agitaçäo) e 'X IND. 2' (aeraçäo), dado pela equaçäo: Y=11,19+2,53'X IND. 1'+2,26'X IND. 2'-2,45'X POT.2 IND.2'. Além de fornecer esses modelos, as metodologias permitiram reduzir o tempo de fermentaçäo em cinquenta por cento
Subject(s)
Biomass , Biotechnology , Statistics/methods , Eucalyptus/microbiology , Fermentation , Fungal Proteins , Paecilomyces , Chromatography, High Pressure Liquid/methods , Culture Media , Food Microbiology , Food Technology , PotentiometryABSTRACT
Na regiäo de Viçosa - MG, foram coletadas raízes finas e solo, de viveiro e de duas florestas de Eucaliptus spp verificando-se a ocorrência de ectomicorrizas. A identificaçäo do fungo ectomicorrízico baseou-se na comparaçäo do micélio e rizomorfas circundantes da ectomicorriza com aqueles encontrados na base do basidiocarpo e conexäo entre micorrizas e basidiocarpos. Também foi observada colonizaçäo endotrófica por descoloraçäo de raízes em KOH 10 e coloraçäo em azul de algodäo. O fungo simbionte foi identificado pela cor, forma e tamanho dos esporos, extraidos do solo através de centrifugaçäo em sacarose. A frequencia anual de ambos tipos micorrízicos foram relacionados com fatores ecológicos como temperatura do ar, pluviosidade e tipo de solo (pH). Verificou-se que, de maneira geral, temperaturas do ar, unidade e elevada e pH de 4,5-7,0, favoreceram a colonizaçäo. Foram identificados as ectomicorrizas: 1- Eucaliptus grandis + Scleroderma spp, 2- Eucalyptus citriodora + Pisolithusss tinctorius, 3- Eucaliptus robusta + P. tinctorius e os fungos endotróficos: Acaulospora screobiculata e Glomus clarum