Hongos anamorfos biodegradan los libros del Área Histórica de la Universidad Central del Ecuador (UCE) / Anamorphous fungi biodegrade the books of the Historical Area from the Central University of Ecuador (CUE)

Determinamos los géneros de hongos anamorfos que contaminan los libros del área de cuarentena y limpieza, dentro del Área Histórica de la Universidad Central del Ecuador (UCE). Realizamos un hisopado aleatorio a una muestra representativa de 50 de estos libros de acuerdo a una Tabla militarizada estándar. También hisopamos como muestra preferencial a 21 libros gravemente contaminados con hongos. Los hisopados tuvieron una superficie de 5x5 cm, friccionando en la pasta, el borde y el interior de estos libros. Las 213 muestras tomadas fueron inoculadas en medio de cultivo Agar Malta. Los medios fueron incubados a una temperatura de 28°C durante 7 días. Realizamos observaciones por microscopía a 40 y 100x además de usar literatura especializada para la identificación hasta el nivel de género de hongos anamorfos. Los géneros más abundantes en este estudio fueron Penicillium (80,2%) y Mucor (8,1%). (AU)

We determined the genera of anamorphic fungi that contaminate the books in the quarantine and cleaning area, within the Historical Area of the Central University of Ecuador (CUE). We performed a random swab on a representative sample of 50 of these books according to a standard militarized Table. We also swabbed as a preferential sample 21 books seriously contaminated with fungi. The swabs had a surface area of 5x5 cm, rubbing on the paste, the edge and the interior of these books. The 213 samples taken were inoculated in Agar Malta culture medium. The media were incubated at a temperature of 28° C for 7 days. We made observations by microscopy at 40 and 100x in addition to using specialized literature for the identification down to the genus level of anamorphic fungi. The most abundant genus in this study were Penicillium(80,2%) and Mucor(8,1%). (AU)

Especies oportunistas de importancia clínica de los géneros bipolaris shoemaker y curvularia boedijn: su caracterización bajo los nuevos criterios taxonómicos / Opportunistic species of clinical relevance in the bipolaris shoemaker & curvularia boedijn genera: its characterization under newest taxonomic criteria

Los géneros fúngicos Bipolaris y Curvularia,incluyen numerosas especies fitopatógenas,saprotrofas y algunas oportunistas emergentes enel ser humano como en otros animales. La distribuciónecológica de ambos taxas es cosmopolita enla gran mayoría de sus integrantes, encontrándosefrecuentemente en hojas, tallos y raíces de diferentespastos, en especial Poaceae, pero tambiénen una gran variedad de dicotiledoneas, aire y sueloen todos los continentes. Cochliobolus, Bipolarisy Curvularia integran un complejo de especiestaxonómicamente confuso, debido a los constantescambios en la nomenclatura de algunos de sus integrantesasexuales (Bipolaris y Curvularia), loscuales se han diferenciado principalmente en basea la morfología de sus conidios, situación a vecesmuy dificultosa debido a que en ambos génerosalgunas especies presentan similares característicasconidiales. Una cuidadosa identificación y unanominación precisa de las especies es crucial parael acceso a la información referente en la literaturamoderna, que gracias a la biología molecularha resuelto muchas de las dudas de la taxonomíabasada solo en el fenotipo.Las especies de ambos géneros (principalmenteCurvularia) pueden afectar a pacientesinmunocomprometidos e inmunocompetentes,en especial B. cynodontis, C. australiensis C.hawaiensis y C. spicifera, causando cuadros clínicosdiversos ya sea superficiales o profundos enmuchas áreas geográficas...

The fungal genera Bipolaris and Curvularia,include numerous plant pathogenic species,saprophitic and some emerging opportunistic inman and other animals. The ecological distributionof both taxa is cosmopolitan in the vast majority ofits members, often being in leaves, stems and rootsof different grasses, especially Poaceae, but also ina variety of dicotyledonous, air and soil on all continents. Cochliobolus, Bipolaris and Curvulariaintegrate a complex of species taxonomically confusingdue to the constant changes in the nomenclatureof some of its asexual members (Bipolarisand Curvularia), which are differentiated mainlybased on the morphology of its conidia, a situationsometimes very difficult because in both generaconidial of some species have similar characteristics. Careful identification and a precise nominationof species is crucial for access to informationconcerning in modern literature, actually thanks tomolecular biology has solved many of the doubtsof taxonomy based only on the phenotype.The species of both genera (mainly Curvularia)can affect immunocompetent or debilitatepatients, especially B. cynodontis, C. australiensis,C. hawaiensis and C.spicifera, causing varioussuperficial or systemic clinical cases in manygeographic areas...

Growth rate inhibition of phytopathogenic fungi by characterized chitosans

The inhibitory effects of fifteen chitosans with different degrees of polymerization (DP) and different degrees of acetylation (F A) on the growth rates (GR) of four phytopathogenic fungi (Alternaria alternata, Botrytis cinerea, Penicillium expansum, and Rhizopus stolonifer) were examined using a 96-well microtiter plate and a microplate reader. The minimum inhibitory concentrations (MICs) of the chitosans ranged from 100 µg × mL-1 to 1,000 µg × mL-1 depending on the fungus tested and the DP and F A of the chitosan. The antifungal activity of the chitosans increased with decreasing F A. Chitosans with low F A and high DP showed the highest inhibitory activity against all four fungi. P. expansum and B. cinerea were relatively less susceptible while A. alternata and R. stolonifer were relatively more sensitive to the chitosan polymers. Scanning electron microscopy of fungi grown on culture media amended with chitosan revealed morphological changes.

Hongos geofílicos en la zona occidental de la región chaqueña (Argentina) / Geophilic fungi in western zone of Chaco Region, Argentina

Mediante las técnicas de Orr y de dilución, se estudiaron muestras de tierra de la zona occidental de la región chaqueña recogidas durante las estaciones de invierno y verano del año 2006. Mediante el anzuelo queratínico se aislaron 22 géneros y 25 especies fúngicas. Los Onygenales estuvieron representados con sólo 8 géneros, principalmente Chrysosporium indicum, Aphanoascus fulvescens y Myceliophthora vellerea, mientras en los no Onigenales, destacan: Paecilomyces lilacinus y Aspergillus fumigatus. En las muestras procesadas por dilución en PDA, se obtuvieron 24 géneros y 43 especies. Entre éstas, el género más frecuente y con mayor diversidad fue Aspergillus, siendo A. fumigatus la especie más representada, siguiendo en importancia los micelios hialinos y dematiáceos sin fructificar, los Penicillium del sub género Biverticillium y los Trichoderma de la sección Trichoderma. Se destaca la presencia de Corynascus verrucosus y C. setosus. Con ambas técnicas no se obtuvieron diferencias significativas respecto del número total de aislamientos entre invierno y verano.

Soil samples from the western zone of Chaco Region and collected during winter and summer of 2006 were studied by means of Orr and dilution techniques. Twenty two genera and 25 fungal species resulted with the use of the keratinic bait. Onygenales were represented by only 8 genera, mainly Chrysosporium indicum, Aphanoascus fulvescens and Myceliophtora vellerea, while Paecilomyces lilacinus and Aspergillus fumigates were present in the not Onygenales group. In samples processed by PDA dilution, 23 genera and 43 species were obtained. Among these, Aspergillus was the most frequent genus and which showed the highest diversity, being A. fumigatus the highest represented species, followed in importance by fructification-free hyaline and dematiaceous mycelia, Penicillium of the sub genus Biverticillium and Trichoderma from the Trichoderma section. The presence of Corynascus verrucosus and C. setosus is also pointed out. There were no significant differences detected under both techniques as regards the overall number of isolations within winter and summer.

Tiña corporis y tiña capitis / Tinea corporis and tinea capitis

La tiña es una infección de la piel, piel cabelluda, uñas o pelo causada por hongos dermatofíticos que invaden el estrato corneo y usan la queratina como nutriente. Existen tres géneros de dermatofitos: Trichophyton, Epidermophyton y Microspurum.

Evaluación in vitro de mutantes de cepas de Trichoderma para el control de Rhizoctonia solani y Phytophthora nicotianae en tomate / In vitro evaluation of Trichoderma strains mutant for the control of Rhizoctonia solani and Phythopthora nicotianae in tomatoes

Se determinó la capacidad antagónica in vitro de mutantes de Trichoderma harzianum (Th), T. piluliferum (Tpi) y T. viride (Tvi), en Rhizoctonia solani cepas 509 (GA 2-1) y 618 (GA 4) y Phytophthora nicotianae cepa 699, aisladas de tomate. Se efectuaron pruebas de antagonismo directo en cultivos duales, metabolitos volátiles y difusibles. Todos los ensayos se desarrollaron a la temperatura y pH óptimos de los 2 patógenos mencionados. Los mutantes se obtuvieron en estudios previos por medio de nitroso guanidinio y luz ultravioleta A (320 nm) y C (256 nm), de progenitores previamente caracterizados y seleccionados por su excelente capacidad para expresar mecanismos múltiples de antagonismo en estos patógenos. Todos los mutantes demostraron cierto grado de capacidad antagónica, los mejores correspondieron a los obtenidos con luz ultravioleta A y C, como: Th 11 A 20.1, Th 11 A 80.1, Th 11 A 160.1 y Th 12 A 10.1, provenientes de las cepas de T. harzianum 11 y 12; mientras que para mutantes de nitroso guanidinio el mejor fue Tvi NG 10, de la cepa T. viride. Los resultados obtenidos se evaluarán en ensayos de invernadero y de campo.

The in vitro antagonic capacity of Trichoderma harzianum (Th), T.piluliferum (Tpi) and T.viride (Tvi)mutants was determined in Rhizoctonia solani strains 509 (GA 2-1) and 618 (GA4) and in Phytophthora nicotianaestrain 699 isolated from tomatoe. Direct antagonism tests were performed in dual cultures, volatile metabolite anddiffusible metabolites. All tests were carried out at the optimum temperature and pH of the two pathogens mentioned above. Mutants resulted from early studies by means of nitrous guanidinio and UV light A (320 nm) and C (256 nm), and they came from parents that had been previously characterized and selected for their excellent ability to express multiple antagonism mechanisms in these pathogenous. All mutants showed a certain degreeof antagonic capacity , being the best of them those obtained under UV light A and C, such as: Th 11 A 20.1, Th 11 A 80.1, Th 11 A 160.1 and Th 12 A 10.1, which came from T.harzianum strains 11 and 12; as to nitrous guanidinio mutants, the best fell in Tvi NG 10 from T. viride strain. Final results will be evaluated in greenhouse and field tests.

Análisis cuantitativo y cualitativo de la aeromicota aislada de la Catedral de Santiago de Compostela (Galicia, España) / Quantitative and qualitative analysis of the airborne fungi isolated in the Cathedral of Santiago de Compostela (Galicia, Spain)

Mediante un estudio de la presencia de mitosporas fúngicas atmosféricas en el interior y exterior de la Catedral de Santiago de Compostela (España) durante un año, a través de un sistema de captación volumétrico viable, se identificaron 28 taxa, principalmente: Alternaria, Aspergillus, Cladosporium y Penicillium. Desde el punto de vista cuantitativo no existen diferencias significativas entre interior/exterior, y en ambos casos las concentraciones son ligeramente más elevadas en primavera-verano. Las especies más abundantes fueron: Penicillium purpurogenum Stoll, con un 94 por ciento en la atmósfera interna y un 82 por ciento en el exterior y Aspergillus fumigatus Fres., con un 65 por ciento y un 63 por ciento respectivamente.

A study was carried out on the atmosphericfungal content in the Cathedral of Santiago deCompostela (Spain) and its exterior during a year, usinga viable volumetric collecting system. A total of 28 taxawere identified, the most abundant of which were:Alternaria, Aspergillus, Cladosporium and Penicillium.In quantitative terms there were no significant indoor/outdoor differences, and the concentrations were slightlyhigher in Spring-Summer in both cases. The mostabundant species were Penicillium purpurogenum Stoll,with 94 percent in the indoor atmosphere and 82 percent outdoors,and Aspergillus fumigatus Fres., representing 65 percent inthe indoor and 63 percent outdoors.

Comportamiento temporal de las mitosporas de Cladosporium en la atmósfera de Galicia (España) / Temporary behaviour of Cladosporium mitospores in the atmosphere of Galicia, Spain

Se ha realizado el recuento de las mitosporas de poblaciones de Cladosporium en la atmósfera de ocho ciudades de Galicia (España), mediante un sistema de captación volumétrica no viable, obteniéndose un total de 40 registros anuales. Los valores promedio de los años de estudio oscilaron entre 96.726 mitosporas en Coruña y 326.898 en Trives, destacando en todas las localidades una mayor abundancia de las mismas durante la época estival. El máximo diario de Cladosporium cladosporioides se registró en Ourense (7.556 mitosporas/m3 el 8 de septiembre de 2004) mientras que el de Cladosporium herbarum correspondió a Trives (7.130 mitosporas/m3 el 8 de julio de 2003). El modelo de comportamiento intradiario varió según la localidad, pero en general se observó una mayor concentración de mitosporas a partir de las 13h.

By using a non viable volumetric capturing system it was possible to count populations of Cladosporiummitospores in the atmosphere of eight cities of Galicia (Spain), yielding a total of 40 annual records. Average values of the examined years ranged from 96.726 mitospores in Coruña and 326.898 in Trives, the highest abundance occurring during summer in all the localities. The daily maximum of Cladosporium cladosporioides was recorded in Ourense (7.556 mitospores/m on September 2004) while that of Cladosporium herbarum was detected in Trives (7.130 mitospores/m on july 8 2003). The intradaily model of behaviour varied according to the locality yet in general a major mitospore concentration could be observed sinceone o´clock p.m.

Patogenicidade de fungos hifomicetos aos pulgões Aphis gossypii Glover e Myzus persicae (Sulzer) (Hemiptera: Aphididae) / Pathogenicity of hyphomycet fungi to aphids Aphis gossypii Glover and Myzus persicae (Sulzer) (Hemiptera: Aphididae)

As espécies de pulgões Aphis gossypii e Myzus persicae são cosmopolitas e polífagas, causando prejuízos em plantas cultivadas. Os efeitos dos fungos entomopatogênicos Beauveria bassiana (isolado IBCB 66), Metarhizium anisopliae (isolado IBCB 121), Paecilomyces fumosoroseus (isolado IBCB 141) e Lecanicillium (= Verticillium) lecanii (isolado JAB 02) foram avaliados sobre ninfas de 3° ínstar de A. gossypii e M. persicae. O experimento foi realizado a 25 ± 1°C, 70 ± 10 por cento de UR e fotofase de 12h. Os pulgões foram colocados em disco foliar (algodão/pimentão) com uma camada de 1 cm de espessura de ágar-água, em placas de Petri. A inoculação de 1 ml de suspensões fúngicas foi realizada com concentrações que variaram de 1,0 x 10(6) a 1,0 x 10(8) conídios/ml de cada fungo. No tratamento testemunha foi adicionado 1 ml de água esterilizada sobre os discos foliares. A mortalidade dos pulgões foi avaliada diariamente. B. bassiana e M. anisopliae causaram mortalidade de 100 por cento no 7° dia após a inoculação, para ambas espécies. L. lecanii foi o fungo que provocou mortalidade mais tardia nos pulgões e M. persicae foi mais suscetível aos fungos que A. gossypii.

The aphids Aphis gossypii and Myzus persicae are cosmopolitan, poliphagous and damage cultivated plants. The effects of the entomopathogenic fungi Beauveria bassiana (isolate IBCB 66), Metarhizium anisopliae (isolate IBCB 121), Paecilomyces fumosoroseus (isolate IBCB 141) and Lecanicillium (= Verticillium) lecanii (isolate JAB 02) on third instar nymphs of A. gossypii and M. persicae were evaluated in the laboratory at 25°C, 70 ± 10 percent RH and 12h photophase. The aphids were transferred to petri dishes with a foliar disk (cotton or pepper) with a layer of 1 cm tick of agar-water. The fungi were applied in a suspension containing 1.0 x 106 to 1.0 x 108 conidia/ml. In the control treatment 1 ml of sterilized water was added to the foliar disks. The mortality of aphids was evaluated daily. B. bassiana and M. anisopliae caused 100 percent mortality at the seventh day after inoculation, for both species. L. lecanii was the fungus that provided mortality later in the aphids and M. persicae was more susceptible to both fungi than A. gossypii.

Incidencia de Myrothecium roridum Tode: Fries, como agente de la pudrición del cuello de plantas de pensamiento (Viola tricolor L. ) en la provincia de Quillota, Chile / Incidence of Myrothecium roridum Tode: Fries as crown root agent of pansy neck plants (Viola tricolor L. ) in the Quillota province, Chile

El pensamiento (Viola tricolor L.) es una especie ornamental de considerable importancia económica para la Provincia de Quillota, especialmente por la producción de semilla híbrida. Desde hace al menos 5 años se ha observado una enfermedad que ocasiona necrosis en la zona del cuello de plantas de pensamiento donde frecuentemente se han observado esporodoquios de Myrothecium roridum. El anßlisis de 114 plantas sintomaticas aportadas por 14 viveros demostró que Botrytis cinerea y M. roridum son los principales fitopatógenos asociados a plantas afectadas por la enfermedad. A travÚs de plaqueo de discos de hojas asintomaticas provenientes de viveros y macizos florales de la región, se demostró que M. roridum estß frecuentemente representado como habitante de la filósfera. En ensayos de patogenicidad sobre semillas y almßcigos, M. roridum afectó en gran medida la germinación de las semillas y ocasionó necrosis en la radícula en emergencia. En plantas adultas, M. roridum provocó pardeamiento y necrosis de la zona del cuello con abundante producción de esporodoquios, ademas de clorosis, marchitamiento y colapso de las plantas.

Peniciliose pulmonar aguda / Acute pulmonary penicilliosis

"Penicillium marneffei" é um fungo endêmico do Sudeste Asiático, que causa infecção disseminada geralmente em pacientes imunodeprimidos infectados pelo vírus HIV. Os autores descrevem o caso de uma mulher de 55 anos de idade com asma leve, que apresentou tosse e hemoptise importante. A paciente foi contaminada a distância do foco endêmico, pela aspiração de esporos de objetos artesanais provenientes da Indonésia. O diagnóstico foi feito através de exame de escarro e cultura para fungos, que revelou a presença de colônias de P. marneffei. O tratamento foi realizado com antifúngico, obtendo boa resposta terapêutica. Salientam-se as conseqüências da globalização, na qual as doenças podem ser difundidas universalmente.

Avaliaçäo in vitro da patogenicidade dos isolados CG17, EP01 e 986 do fungo Beauveria bassiana (balsamo) Vuillemin sobre larvas do carrapato Anocentor nitens (Neumann, 1897) (Acari: Ixodidae) / Patogenicity of isolates CG17, EP01 and 986 of the fungi Beauveria bassiana on larvae of the tick Anocentor nitens (Neumann, 1897) (Acari: Ixodidae) in laboratory

A patogenicidade in vitro de três isolados do fungo Beauveria bassiana, CG17 e EP01 e 986 foi avaliada em larvas do carrapato Anocenter nitens mantidas em temperatura controlada (27ºC e 80 por cento U.R.). A susceptibilidade das larvas aos isolados foi determinada experimentalmente por imersäo de grupos de larvas näo alimentadas com 25mg de larvas por grupo, durante três minutos, em quatro concentraçöes (10(5), 10(6), 10(7) e 10(8) conídios/ml) de cada isolado e um grupo controle imerso em água (com dez repetiçöes para cada tratamento). Após dez dias de infecçäo, a concentraçäo 10(8) causou a mortalidade de aproximadamente 93 por cento das larvas para todos os isolados, e a concentraçäo 10(5) causou a mortalidade de 7,6 por cento, 17,5 por cento e 43 por cento, nos tratamentos com os isolados 986, EP01 e CG17, respectivamente. A mortalidade média de larvas do grupo controle näo excedeu a 0,9 por cento, fato este que demonstra o poder patogênico deste fungo em larvas de A. nitens. A CL 50 para os isolados 986, CG17 e EP01 foi 1,8 X 10(7); 1,6 X 10(6) e 2,5 X 10(7), respectivamente.

In vitro interaction of Brazilian strains of the Nematode-trapping fungi Arthrobotrys spp. on Panagrellus sp. and Cooperia punctata

In vitro tests were carried out to verify the activity of 26 Brazilian isolates of predatory fungi of the genus Arthrobotrys on a free-living nematode (Panagrellus sp.) and on infective larvae of Cooperia punctata, a parasitic gastrointestinal nematode of cattle. The results showed that the free-living nematode Panagrellus sp. was the most preyed upon, compared to C. punctata, for all the fungal treatments. Also, variable predatory capacity was observed for different fungal isolates belonging to the same genus when applied to different nematode species

In vitro activity of Brazilian strains of the predatory fungi Arthrobotrys spp. on free-living nematodes and infective larvae of Haemonchus placei

In vitro tests were carried out to assess the activity of 26 Brazilian isolates of predatory fungi of the genus Arthrobotrys on a free-living nematode (Panagrellus sp.) and on infective larvae of Haemonchus placei, a parasitic gastrointestinal nematode of cattle. The results showed that the free-living nematode Panagrellus sp. was the most preyed upon, compared to H. placei, for all the fungal treatments. Also, variable predatory capacity was observed for different fungal isolates belonging to the same genus when applied to different nematode species

Differential in vitro pathogenicity of predatory fungi of the genus Monacrosporium for phytonematodes, free-living nematodes and parasitic nematodes of cattle

In vitro tests were carried out on the pathogenicity of nine isolates of the predatory fungi of the genus Monacrosporium (5 M. sinense isolates, 3 M. appendiculatum and 1 M. thaumasium isolate) for a phytonematode (second stage juveniles from Meloidogyne incognita, race 3), a free-living nematode (Panagrellus spp), and two gastrointestinal parasitic nematodes of cattle (infective larvae of Cooperia punctata and Haemonchus placei). A suspension containing 2,000 nematodes from each species was added to Petri dishes containing fungi and grown on 2 percent water-agar medium at 25oC in the dark for up to 7 days. The dishes were examined every other day for 7 days and predation-free nematodes were counted. The results showed that the free-living nematodes, Panagrellus spp, were the most susceptible (P<0.05), followed by the phytonematode M. incognita, while the controls were 98.5 percent viable. However, a variable susceptibility of the nematodes to different fungi was observed. This indicates that the use of predatory fungi for the environmental control of nematodes will be limited by the multiplicity of nematodes in the environment and their differential susceptibility to fungal isolates of the same genus

Aerosporas fúngicas del área oriente de Santiago (1996-1997) / Fungal aerospores from orient area of Santiago (1996-1997)

Utilizando un captador Burkard se estudia la aeromicrobiota presente en Santiago oriente durante 12 meses (agosto 1996 a julio 1997) identificando las aerosporas fúngicas por microscopía directa. Estas fueron agrupadas en 19 categorías taxonómicas, correspondiendo el 76.2 porciento a deuteromycetes, el 16.6 porciento a basidiomycetes, 2 porciento a ascomycetes y el 8.3 porciento a aerosporas no identificadas. En nuestro registro predominan los hongos dematiáceos debido a la gran pasiencia de cladosporium, 73 porciento. Las basidiosporas ( no identificadas) constituyeron el 8,4 porciento, carbones 4.3 porciento, ascosporas (no identificadas) 1.6 porciento, alternaria 1 porciento y el resto de los géneros con frecuencia menores al 1 porciento. Cladosporium presenta un contenido aéreo mayor en otoño (abril) como epicoccun y stemphylium; las basidiosporas, conidios de aspergillus/penicillium y ascosporas aumentan en los meses de invierno. Alternaria se dispersa con igual frecuencia durante primavera y otoño. Ganoderma y helminthos-porium aumentan durante el verano. Con el registro de tres años consecutivos se confeccionará un calendario aeromicológico que permita a los pacientes con rinitis o asma reconocer los períodos de mayor dispersión aérea de estos alérgenos

Selection of Beauveria bassiana and Metarhizium anisopliae isolates to control Triatoma infestans

Twenty three isolates of Beauveria bassiana and 13 isolates of Metarhizium anisopliae were tested on third instar nymphs of Triatoma infestans, a serious vector of Chagas disease. Pathogenicity tests at saturated humidity showed that this insect is very susceptible to fungal infection. At lower relative humidity (50 per cent), conditions expected in the vector microhabitat, virulence was significantly different among isolates. Cumulative mortality 15 days after treatment varied from 17.5 to 97.5 per cent and estimates of 50 per cent survival time varied from 6 to 11 days. Maintaining lower relative humidity, four B. bassiana and two M. anisopliae isolates were selected for analysis of virulence at different conidial concentrations and temperatures. Lethal concentration sufficient to kill 50 per cent of insects (LC50) varied from 7.1x10 5 to 4.3x10 6 conidia/ml, for a B. bassiana isolate (CG 14) and a M. anisopliae isolate (CG 491) respectively. Most isolates, particularly B. bassiana isolates CG 24 and CG 306, proved to be more virulent at 25 and 30ºC, compared to 15 and 20ºC. The differential virulence at 50 per cent humidity observed among some B. bassiana isolates was not correlated to phenetic groups in cluster analysis of RAPD markers. In fact, the B. bassiana isolates analyzed presented a high homogeneity (>73 per cent similarity).

Biodeterioro de materiales plásticos por microhongos / Biodegradation of plastic compounds by microfungi

Mediante la selección de 8 compuestos plásticos utilizados en el mercado, adquiridos a la firma Aldrich Química SRL (Alemania), se valoró su capacidad de ser asimiladas como única fuente de carbono in vitro, por 2 grupos de microhongos pertenecientes a los asco-deuteromycetes. Estos compuestos fueron: poliestireno, polivinilacetato, poliacrilonitrito, policaprolactona, polimetacrilato de metilo, polivinilcloruro, acetato de celulosa y polietileno. Solo la policaprolactona y el polivinilacetato fueron utilizados por los 2 grupos de hongos en estudio, en especial por cepas de aspergillus, chaetomiun, cladosporium, fusarium, penicillium y scopulariopsis. La policaprolactona fue el polímero más utilizado entre ph 6.5 a 8. Las diferentes especies pertenecientes a los géneros aspergillus y fusarium, presentaron la mayor actividad en la utilización de estos compusetos