Genetic analyses place most Spanish isolates of Beauveria bassiana in a molecular group with word-wide distribution

<p>Abstract</p> <p>Background</p> <p>The entomopathogenic anamorphic fungus <it>Beauveria bassiana </it>is currently used as a biocontrol agent (BCA) of insects. Fifty-seven <it>Beauveria bassiana </it>isolates -53 from Spain- were characterized, integrating group I intron insertion patterns at the 3'-end of the nuclear large subunit ribosomal gene (LSU rDNA) and elongation factor 1-alpha (EF1-α) phylogenetic information, in order to assess the genetic structure and diversity of this Spanish collection of <it>B. bassiana</it>.</p> <p>Results</p> <p>Group I intron genotype analysis was based on the four highly conserved insertion sites of the LSU (Ec2653, Ec2449, Ec2066, Ec1921). Of the 16 possible combinations/genotypes, only four were detected, two of which were predominant, containing 44 and 9 members out of 57 isolates, respectively. Interestingly, the members of the latter two genotypes showed unique differences in their growth temperatures. In follow, EF1-α phylogeny served to classify most of the strains in the <it>B. bassiana s.s</it>. (<it>sensu stricto</it>) group and separate them into 5 molecular subgroups, all of which contained a group I intron belonging to the IC1 subtype at the Ec1921 position. A number of parameters such as thermal growth or origin (host, geographic location and climatic conditions) were also examined but in general no association could be found.</p> <p>Conclusion</p> <p>Most Spanish <it>B. bassiana </it>isolates (77.2%) are grouped into a major phylogenetic subgroup with word-wide distribution. However, high phylogenetic diversity was also detected among Spanish isolates from close geographic zones with low climatic variation. In general, no correlation was observed between the molecular distribution and geographic origin or climatic characteristics where the Spanish <it>B. bassiana </it>isolates were sampled.</p

Pathogenicity and thermal biology of mitosporic fungi as potential microbial control agents of Varroa destructor (Acari: Mesostigmata), an ectoparasitic mite of honey bee, Apis mellifera (Hymenoptera: Apidae)

Pathogenicity and thermal biology (tb) were investigated for entomopahogenic fungi isolates (EFI), which were examined as potential biocontrol agents of the ectoparasite Varroa destructor, the major disease of honey bees in Andalusia (Spain). All 16 of the assayed EFI were pathogenic to V. destructor, while two of them were exceptionally pathogenic to the mite: Metarhizium anisopliae 01/121-Su [AST 35.0 h, 100% mortality at 72 h post infection (p.i.)] and Beauveria bassiana 01/103-Su (AST 39.4 h, 96.0% mortality at 72 h p.i.). The tb of the five most virulent isolates against the mite was investigated at seven temperatures (10–40 °C) by using a modified generalized beta function that accounted for 79.8–96.4% of the data variance. Optimum temperatures and maximum temperatures for growth ranged from 24.9 to 31.2 °C and from 30.1 to 35.0 °C respectively. On the basis of their pathogenicity, thermal requirements and safety to honey bees, two isolates showed promise as candidates for V. destructor control

Assessing the effect of soil treatments with the entomopathogenic fungus Metarhizium anisopliae (Metchnikoff) Sorokin against puparia of Bactrocera oleae (Diptera: Tephritidae) on soil dwelling non target arthropods

5 páginas, 4 figuras.-- Trabajo presentado por el Working Group: "Integrated protection of Olive Crops" al Meeting de Bragança (Portugal) celebrado del 10 al 12 de Octubre de 2007.The objective of this study was to determine the persistence of the autochthonous Metarhizium anisopliae EAMa 01/58-Su isolate in the soil when applied beneath olive trees for controlling olive fly puparia and to elucidate its possible effect on non-target soil dwelling arthropod communities. For that, we selected 200 olives trees in an organic olive orchard at the province of Málaga(Spain) to be sprayed either with a 2.5 x·107 conidia m-2 suspension of the fungus on the ground beneath the tree canopy (100 trees) or with the blank formulation as controls (100 trees). Before fungal treatments, we selected 10 trees from the treated ones for evaluating both the possible presence of indigenous entomopathogenic fungi in the soil by using the Galleria Bait Method and the evolution of the conidial densities in the soil after spraying. The entomopathogenic fungus Beauveria bassiana (Balsamo) Vuill. was the most common species, being found in all the samples, while M. anisopliae was found only in one sample. After spraying the 100 treated and 100 control trees, soil samples beneath the 10 selected trees from the top 10 cm were taken to calculate the number of conidial forming units per gram of soil at 1, 7, 14, 28, 35, 42, 49, 56 and 63 days after treatment respectively. Our preliminary data indicate that the soil ecosystem favours the persistence of this autochthonous isolate, which could allow long term protection of the crop against olive fly puparia. In order to assess the possible effect of the fungal treatment on soil arthropod populations, 40 pitfall traps (7.5 cm diameter by 10 cm deep) placed beneath the tree canopy of randomly selected 20 treated and 20 controls trees, were sampled every two weeks. Our preliminary data indicate that formicidae species are the most abundant arthropods trapped, but no infected insects have been found in field as a result of the treatment to now.Peer reviewe

Potential of an indigenous strain of the entomopathogenic fungus Beauveria bassiana as a biological control agent against the Red Palm Weevil, Rhynchophorus ferrugineus

The potential of a strain of Beauveria bassiana (Ascomycota: Clavicipitaceae) obtained from a naturally infected Rhynchophorus ferrugineus (Coleoptera: Curculionidae) pupa as a biological control agent against this weevil was evaluated both in the laboratory and in semi-field assays. Laboratory results indicate that this strain of B. bassiana can infect eggs, larvae and adults of R. ferrugineus (LC50 from 6.3×107 to 3.0×109 conidia per ml). However, mortality was not the only indicator of treatment efficacy because adults of either sex inoculated with the fungus efficiently transmitted the disease to untreated adults of the opposite sex, with male-to-female and female-to-male rates of transmission of 55% and 60%, respectively. In addition, treatment with B. bassiana significantly reduced fecundity (up to 62.6%) and egg hatching (32.8%) in pairing combinations with fungus-challenged males, females or both sexes. Likewise, 30-35% increase in larval mortality was observed in larvae obtained from eggs from fungus-challenged females or from untreated females coupled with inoculated males, resulting in an overall 78% progeny reduction. Semi-field preventive assays on potted 5-year old Phoenix canariensis palms, with efficacies up to 85.7%, confirmed the potential of this strain as a biological control agent against R. ferrugineus. © 2010 Elsevier Inc

Detection of potentially valuable polymorphisms in four group I intron insertion sites at the 3'-end of the LSU rDNA genes in biocontrol isolates of <it>Metarhizium anisopliae</it>

Abstract Background The entomopathogenic anamorphic fungus Metarhizum anisopliae is currently used as a biocontrol agent (BCA) of insects. In the present work, we analyzed the sequence data obtained from group I introns in the large subunit (LSU) of rDNA genes with a view to determining the genetic diversity present in an autochthonous collection of twenty-six M. anisopliae isolates selected as BCAs. Results DNA fragments corresponding to the 3'-end of the nuclear LSU rDNA genes of 26 M. anisopliae isolates were amplified by PCR. The amplicon sizes ranged from 0.8 to 3.4-kb. Four intron insertion sites, according to Escherichia coli J01695 numbering, were detected- Ec1921, Ec2066, Ec2449 and Ec2563- after sequencing and analysis of the PCR products. The presence/absence of introns allowed the 26 isolates to be distributed into seven genotypes. Nine of the isolates tested showed no introns, 4 had only one, 3 two, and 10 displayed three introns. The most frequent insertion sites were Ec1921 and Ec2449. Of the 26 isolates, 11 showed insertions at Ec2563 and a 1754-bp sequence was observed in ten of them. The most-parsimonious (MP) tree obtained from parsimony analysis of the introns revealed a main set containing four-groups that corresponded to the four insertion sites. Conclusion Four insertion sites of group I introns in the LSU rDNA genes allowed the establishment of seven genotypes among the twenty-six biocontrol isolates of M. anisopliae. Intron insertions at the Ec2563 site were observed for first time in this species.</p

[Correspondencia de Camilo Díaz Baliño] , 1917-1936

Mss. (algúns en fotocopia) autógrafo e mecanografiadoResumen: Correspondencia recibida por Camilo Díaz Baliño entre os anos 1917-1936 relacionada con asuntos persoais e laboraisBiblioteca de GaliciaForma de ingreso: Depósito. Fuente de ingreso: Díaz Pardo, Isaac. Fecha de ingreso: 2011. Propietario: Herdeiros de Isaac Díaz PardoDixitalización Telefónica-IDP 2012Contén : Cartas de: Manuel Abelenda (1 páx.) -- Cesar Alvarez (1 páx.) -- Carlos Amigo Collía (2 páxs.) -- Banco Hispano-Americano (2 páxs.) -- Alfonso Barreiro (3 páxs.) -- Eliseo Barros Gamallo (1 páx.),(2 páxs.) -- Ramón Beade (2 páxs.) -- Benito(2 páxs.) -- Fernando Blanco(1 páx.) -- José Bouzas y Cardama (1 páx.) -- Albino Bouzó Fernández (1 páx.),(2 páxs) -- José Cabada Vázquez (4 páxs.),(1 páx.),(1 páx.) --Salvador Cabeza (1 páx.) -- Antonio Carballa (1 páx.) -- Leandro y Euxenio Carré (2 páxs.) -- V. Carro (1 páx.) -- Santiago Casares (1 páx.) -- Alvaro Cebreiro (2 páxs.) -- Centro Gallego de Buenos Aires (1 páx.),(1 páx.) -- Compostela (2 páxs.) -- Manolo: Continental (2 páxs.) -- Coral de Ruada (1 páx.),(2 páxs.) -- Amando Cotarelo(1 páx.),(1 páx.) -- Eduardo Dorado Xaneiro (8 páx.) -- Círculo Mercantil e Idustrial: Ramón Fernández (1 páx.) --Virgilio Fernández(3 páxs.) -- Ramón Fernández Mato (2 páxs.) -- B. Ferreiro(1 páx.) -- Jenaro de la Fuente (1 páx.) -- Isaac Fraga: Espéctaculos Empresa Fraga (1 páx.),(1 páx.) -- Antonio Folgar Lema(1 páx.)--Alicio Garcitoral (1 páx.) -- Cándido González Raño (1 páx.) -- Daniel González Rodriguez (2 páxs.),(2 páxs.) -- Edurardo G.del Río (1 páx.) -- Hermanos Hernández (2 páxs.),(1 páx.),(1 páx.),(1 páx.) -- José Iglesias Sánchez (2 páxs.) -- Irmandades da Fala (1 páx.) -- José Silva? (2 páxs.) -- Arturo Longa (1 páx.) -- Casimiro López (1 páx.) -- Edmundo López (1 páx.),(1 páx.) -- Eduardo R. Losada y Rebellón (2 páx.) -- Carlos Maside (1 páx.) -- Enrique Mayer (1 páx.) -- Antonio Méndez Laserna (1 páx.) -- Anselmo Padín (1 páx.) -- Xavier Pardo (1 páx.) -- Partido Republicano Radical Socialista (1 páx.) -- Pérez Bustamante (1 páx.) -- Modesto Piñeiro (2 páxs.) -- Salustiano Portela (2 páxs.) -- José Seijo Rubio (2 páxs.) -- Suarez Picallo (2 páxs.) -- Luis Losada (1 páx), (1 páx.) -- Ricardo Valdés (2 páxs.),(2 páxs.),(2 páxs.),(1 páx.) -- A.Nilo Varela (1 páx.),(2 páxs.),(2 páxs.) -- Juan Varela de Limia (1 páx.) -- Victorino? Varela (1 páx.) -- Jesús Varela (3 páxs.) -- F.Vázquez Suarez (1 páx.) -- Santiago Vidal Gimeno (1 páx.) -- Pedro Vieitez (1 páx.) -- M. Villar (2 páxs.) -- Anónima (1 páx.) -- Anónima (1 páx.