Assessment of microfungi in fungus gardens free of the leaf-cutting ant Atta sexdens rubropilosa (Hymenoptera: Formicidae)

The purpose of this study was to determine the microfungi present in young nests of Atta sexdens rubropilosa when the fungus gardens were deprived of worker ants. The results were compared with another study in which worker ants had been killed by using toxic baits, and some species such as Acremonium kiliense, Escovopsis weberi, Moniliella suaveolens and Trichoderma sp. were confirmed among the most common inhabitants of this microenvironment, but differences in composition and proportion of species were observed. The importance and the role of these and other species of fungi within the symbiosis are discussed.

Cochliobolus heliconiae sp nov (Ascomycota)

A new species of Cochliobolus, C. heliconiae, is described and illustrated. The species is heterothallic and ascomata were produced in pure culture using two isolates of its Bipolaris anamorph, also described as new, obtained from lesions on Heliconia spp. in northern Australia.

Phyllosticta species on orchids (Orchidaceae), introducing Phyllosticta speewahensis sp. nov. (Phyllostictaceae, Ascomycota) from northern Australia

Several species of Phyllosticta (syn. Guignardia) have been described from orchids worldwide. A new species, Phyllosticta speewahensis, is proposed for a specimen isolated from leaf spots on a hybrid Vanda orchid in northern Queensland, Australia. Phylogenetic analysis of the nrDNA internal transcribed spacer region (ITS) and partial translation elongation factor 1-alpha (TEF1) gene sequences showed that P. speewahensis is most closely related to P. hostae. The likelihood that orchids harbour further cryptic species of endophytic and pathogenic Phyllosticta species is discussed.

Caracterização molecular de microorganismos do ecossistema agricola do cerrado. III. Acremonium strictum.

2003

Ensayo con fitoterápicos para la erradicación del endófito Acremonium coenophilalum en semillas de festuca

p.1-10

Parasitismo de tamarixia triozae (Burks) (hymenoptera: eulophidae) sobre bacteria cockerelli (sulc.) hemíptera: triozidae) y su interacción con aislamientos del hongo entomopatógeno beauveria bassiana (bálsamo) vuill (ascomycota: hypocreales).

Tesis (Doctor en Ciencias con especialidad en Microbiología) UANL, 2014.

Extraction of Glucan from Acremonium Diospyri and Its Application in Macrobrachium Rosenbergii Larval Rearing System Along With Bacterians as Microspheres

Present work is aimed at development of an appropriate microbial technology for protection of larvae of macrobrachium rosenbergii from disease and to increase survival rate in hatcheries. Application of immunostimulants to activate the immune system of cultured animals against pathogen is the widely accepted alternative to antibiotics in aquaculture. The most important immunostimulant is glucan. Therefore a research programme entitled as extraction of glucan from Acremonium diospyri and its application in macrobrachium rosenbergii larval rearing system along with bacterians as microspheres. The main objectives of the study are development of aquaculture grade glucan from acremonium diospyri, microencapsulated drug delivery system for the larvae of M. rosenbergii and microencapsulated glucan with bacterian preparation for the enhanced production of M. rosenbergii in larval rearing system. Based on the results of field trials microencapsulated glucan with bacterin preparation, it is concluded that the microencapsulated preparation at a concentration of 25g per million larvae once in seven days will enhance the production and quality seed of M. rosenbergii.

Application of bacterins and yeast Acremonium dyosporii to protect the larvae of Macrobrachium rosenbergii from vibriosis

The fresh water prawn, Macrobrachium rosenbergii, has proven potential for use as an aquaculture species (Hanson & Goodwin, 1997; Kurup, 1984). In India alone, culture of this species of prawn in low saline areas requires about 200 million seed per year (Kurup, 1984). In hatcheries poor survival rate has been associated with vibriosis at di#erent stages of the larval cycle. Members of the family Vibrionaceae associated with the larvae of M. rosenbergii were shown to be pathogenic under laboratory conditions (Bhat et al., 2000, in press). Vibrios have been associated with mortality of penaeid prawns by several workers (Aquacop, 1977; Hameed, 1993; Karunasagar et al., 1994). Two methods have been suggested to protect both the larvae and juveniles from vibriosis; one is the administration of bacterins prepared from pathogenic strains (Itami et al., 1989, 1991; Adams, 1991; Song & Sung, 1990; Sung et al., 1991) and the other is the utilization of yeast 1-3 and 1-6 glucans as immunostimulants for enhancing the non-specific defense system (Sung et al., 1994; Song et al., 1997). In the light of these observations it was hypothesised that bacterins and yeast glucans may also be e#ective in protecting the larvae of M. rosenbergii from vibriosis as has been achieved in the case of penaeids. To examine this hypothesis, the ability of bacterins and an extracellular glucan-producing yeast to increase the overall survival and metamorphosis of larvae in a hatchery, as well as to protect against an experimental challenge under laboratory conditions, was evaluated

Alkali insoluble glucan extracted from Acremonium diospyri is a more potent immunostimulant in the Indian White Shrimp, Fenneropenaeus indicus than alkali soluble glucan

E¡ect of an extraction method on the structure of glucan and its immunostimulatory response in Fenneropenaeus indicus was investigated. Here we extracted alkali insoluble glucan (AIG) and alkali soluble glucan (ASG) from a ¢lamentous fungi Acremonium diospyri following alkali^acid hydrolysis and the sodium hypochlorite oxidation and dimethyl sulphoxide extraction method respectively. Structural analysis showed that 85% of glucan in AIG was a (1 !3)-b-D-glucan and it increased the prophenoloxidase and reactive oxygen intermediate activity when administered to F. indicus. On the other hand, ASG, which contained 93% (1 !3)-a-glucan, did not induce signi¢cant immune response in shrimp. Here we report that the di¡erence in immunostimulatory potential between AIG and ASG is due to the di¡erence in the percentage of (1 !3)-b-D-glucans present in each preparation, which varies with the method of extraction employed. Also our observations suggest that glucan can be used as a potential immunostimulant to shrimp, provided it contains (1 !3)-b-D-glucan as the major fraction.

Evolutionary history of vegetative reproduction in Porpidia s. l. (lichen-forming ascomycota)

The evolutionary history of gains and losses of vegetative reproductive propagules (soredia) in Porpidia s.l., a group of lichen-forming ascomycetes, was clarified using Bayesian Markov chain Monte Carlo (MCMC) approaches to monophyly tests and a combined MCMC and maximum likelihood approach to ancestral character state reconstructions. The MCMC framework provided confidence estimates for the reconstructions of relationships and ancestral character states, which formed the basis for tests of evolutionary hypotheses. Monophyly tests rejected all hypotheses that predicted any clustering of reproductive modes in extant taxa. In addition, a nearest-neighbor statistic could not reject the hypothesis that the vegetative reproductive mode is randomly distributed throughout the group. These results show that transitions between presence and absence of the vegetative reproductive mode within Porpidia s.l. occurred several times and independently of each other. Likelihood reconstructions of ancestral character states at selected nodes suggest that - contrary to previous thought - the ancestor to Porpidia s.l. already possessed the vegetative reproductive mode. Furthermore, transition rates are reconstructed asymmetrically with the vegetative reproductive mode being gained at a much lower rate than it is lost. A cautious note has to be added, because a simulation study showed that the ancestral character state reconstructions were highly dependent on taxon sampling. However, our central conclusions, particularly the higher rate of change from vegetative reproductive mode present to absent than vice versa within Porpidia s.l., were found to be broadly independent of taxon sampling. [Ancestral character state reconstructions; Ascomycota, Bayesian inference; hypothesis testing; likelihood; MCMC; Porpidia; reproductive systems]

Control of Leveillula taurica in tomato by Acremonium alternatum is by induction of resistance, not Hyperparasitism

Spores of the hyperparasite Acremonium alternatum reduced powdery mildew infection by Leveillula taurica on greenhouse tomato. The effect was slightly increased when spores were applied killed, and therefore not due to direct parasitism. The effect was systemic, protecting untreated leaves above the treated ones. Spores killed by heat had more effect than when killed by UV, so the effect was presumably due to induction of host resistance by substances released when cells were heat killed. The size of the effect depended upon leaf age and level of infection. Effects on primary infection and expansion of successful infections appear to be under independent control.

Morfoanatomia comparada do talo de duas espécies de Parmotrema (Parmeliaceae, Ascomycota liquenizados) com rizinas dimórficas

Utilizando técnicas convencionais para estudos histológicos em microscopia de luz com auxílio de luz polarizada, se descreve e compara a anatomia do talo de duas espécies de Parmotrema, Parmotrema consors e Parmotrema cf. reparatum, com rizinas dimórficas e máculas efiguradas, antigamente incluídas em Canomaculina. Os dados obtidos neste estudo mostram que as duas espécies são anatomicamente distintas em relação às características do epicórtex, córtex superior e rizinas. Parmotrema cf. reparatum é anatomicamente similar ao grupo de Parmotrema com máculas reticulares (antigamente incluídas em Rimelia) previamente estudados. Os polissacarídeos típicos do epicórtex e córtex superior do grupo de espécies de Parmotrema com rizinas dimórficas possuem diferenciação histoquímica daqueles mencionados para o epicórtex e córtex superior do grupo de Parmotrema com máculas reticulares.

Anatomia comparada do talo de duas espécies de Parmotrema (Parmeliaceae, Ascomycota liquenizados) com máculas reticulares

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Thallus structure and isidium development in two Parmeliaceae species (lichenized Ascomycota)

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)