Endo- and epiphytic fungal communities of olive twigs is influenced by cultivar and olive knot infection

Olive tree phyllosphere is colonized by a diverse microbial assemblage that may interact with pathogenic fungi, making them potential candidates for disease supression. Olive knot (OK) is a disease caused by the bacterium Pseudomonas savastanoi pv. savastanoi (Psv.) with significant economic losses in olive tree (Olea europaea L.). With this work we want to evaluate the effect of cultivar and OK infection on both endo- and epiphytic fungal community inhabiting olive twig tissues. For this, fungal composition and diversity was assessed in both asymptomatic and OK-symptomatic twigs of tree co-occurring olive cultivars with different susceptibilities to OK disease. The identification of isolated species was performed by ITS rDNA sequencing. The cultivar and OK infection were important in shaping both endophytic and epiphytic fungal communities. Fungal community composition was found to differ significantly (p=0.005) between olive tree cultivars, being Nectriaceae the dominant family in cvs. Cobrançosa and Verdeal Transmontana, whereas Pleosporaceae was dominant in the cv. Madural. Epiphytic and endophytic fungal communities also differed in size and in composition in asymptomatic and OK-symptomatic twigs, for the three cultivars. In general, asymptomatic twigs were more diverse and rich (up to 1.4-fold) when compared to OK-symptomatic twigs. Among the species identified in the asymptomatic tissues, Cladosporium cladosporioides and Chromelosporium carneum were the most frequently isolated within epiphytic and endophytic community, respectively; whereas in the OK-symptomatic tissues Cladosporium sp. and Fusarium lateritium were the most frequently isolated within epiphytic and endophytic community, respectively. According to indicator species analysis C. carneum, Pyronema dosmesticum and Phoma aloes (IndVal up to 0.56) may be promising species in the OK suppression. Better acknowledgement should be developed in order to uncover their role on plant health.FEDER funds through COMPETE (Programa Operacional Factores de Competitividade} and by national funds by FCT [Fundação para a Ciência e a Tecnologia) in the framework of the project EXCL/AGR-PRO/0591/2012. T. Gomes thanks FCT, POPH-QREN and FSE for PhD SFRH/BD/98127/2013 Grantinfo:eu-repo/semantics/publishedVersio

Barcoding of entomopathogenic fungi from olive tree pests : prospects and limitations

From all the barcoding initiatives in progress, fungal barcode is probably the one where more difficulties have been encountered. While for plants and animais the barcode regions were easy to define, for fungi the choice was not so straightforward. The internal transcribed spacer (ITS) region was one of the proposed DNA regions for barcoding fungi. This is an extensively used region, for molecular systematic and identification of species, being probably the most widely sequenced DNA region of fungi. This is due to the simplicity of the amplification, related to the multicopy nature of the rDNA; the possibility of using universal primers; and the high levei of sequence variation that occurs even between closely related species. Furthermore, a significant number of identified sequences for comparison are available in the GenBank database. Although the ITS region of rDNA was chosen for some groups of fungi, the use of this region presents very limited application for others, especially for Ascomycetes. As some of the most important entomopathogenic fungi are Ascomycetes, belonging to genera Beauveria, Cordyceps, Isaria, Lecanicillium and Paecilomyces, the use of the ITS region for barcoding purpose are being complemented with other regions. This work, based on the identification of fungal entomopathogens isolated directly from cadavers of one of the major pests in olive graves, the olive moth iPrevs oleae Bern.), intends to illustrate the application of the ITS region to identify these fungal species. The use of this region proved to be useful for the identification of most of the entomopathogenic fungi found in dead larvae and pupae of P. oleae. However, the use ot ITS region for barcode purposes did not allow the identification of several isolates, proving the requiremerít of using a second barcoding region, to enable full fungal identification.This work has been supported by FCT (PTDC/AGR-AAM/02600/2008)

Identification of fungi isolated from the olive moth (Prays oleae Bern.) based on ITS region

Fundação para a Ciência e Tecnologia (FCT) - Project PTDC/AGR-AAM/102600/200

Fungal diversity among different annual generations of Prays oleae

Comunicação em painelThe olives and olive oil production are important agricultural activities in Portugal. In the region of Trás-os-Montes, olive orchards are strongly affected by Prays oleae Bern., which is responsible for high losses in the olive production, as much as 40% of the expected yield. This lepidopteran presents three generations per year (phyllophagous, antophagous and carpophagous) that damage the olive tree in different organs (leaves, flowers and fruits, respectively). In an attempt to identify fungi that might cause the death of olive moths, larvae and pupae of those three annual generations were collected and surveyed for natural fungal infection. After their isolation, the fungal agents were molecularly identified by sequencing the amplified internal transcribed spacer (ITS) region of rDNA. In the present work, the diversity of fungal species associated to P. oleae, in several olive orchards located in Trás-os-Montes region, is discussed. The diversity and abundance of fungal species differed between all three generations. Higher diversity was found in the carpophagous generation, followed by the antophagous and phyllophagous generations. The use of already adapted fungal species to control one of the major pests of olive groves will increase the success of a future biocontrol strategy. In this context, the identification of fungi associated to P. oleae from olive orchards provided a pool of potential biocontrol agents. In this work, Beauveria bassiana proved to be the most promising fungus to be used as biocontrol agent against olive moth, being strongly associated to the phyllophagous generation. Other fungal species presenting entomopathogenic, antagonistic and phytopathogenic characteristics were also found.This work has been supported by FCT (PTDC/AGR-AAM/102600/2008)

Manejo de colônias de abelhas-sem-ferrão.

Introdução; Ninho; Escolha de espécie; Localização do meliponário; Caixa racional; Instalação das colmeias; Revisão das colônias; Fortalecimeto das colônias; Alimentação; Divisão de colônias; Inimigos naturais; Produção de mel; Referências.bitstream/item/95760/1/CT219.pd

Optical Properties of Strained Graphene

The optical conductivity of graphene strained uniaxially is studied within the Kubo-Greenwood formalism. Focusing on inter-band absorption, we analyze and quantify the breakdown of universal transparency in the visible region of the spectrum, and analytically characterize the transparency as a function of strain and polarization. Measuring transmittance as a function of incident polarization directly reflects the magnitude and direction of strain. Moreover, direction-dependent selection rules permit identification of the lattice orientation by monitoring the van-Hove transitions. These photoelastic effects in graphene can be explored towards atomically thin, broadband optical elements

Energy of general 4-dimensional stationary axisymmetric spacetime in the teleparallel geometry

The field equation with the cosmological constant term is derived and the energy of the general 4-dimensional stationary axisymmetric spacetime is studied in the context of the hamiltonian formulation of the teleparallel equivalent of general relativity (TEGR). We find that, by means of the integral form of the constraints equations of the formalism naturally without any restriction on the metric parameters, the energy for the asymptotically flat/de Sitter/Anti-de Sitter stationary spacetimes in the Boyer-Lindquist coordinate can be expressed as $E=\frac{1}{8\pi}\int_S d\theta d\phi(sin\theta \sqrt{g_{\theta\theta}}+\sqrt{g_{\phi\phi}}-(1/\sqrt{g_{rr}})(\partial{\sqrt{g_ {\theta\theta} g_{\phi\phi}}}/\partial r))$. It is surprised to learn that the energy expression is relevant to the metric components $g_{rr}$, $g_{\theta\theta}$ and $g_{\phi\phi}$ only. As examples, by using this formula we calculate the energies of the Kerr-Newman (KN), Kerr-Newman Anti-de Sitter (KN-AdS), Kaluza-Klein, and Cveti\v{c}-Youm spacetimes.Comment: 12 page

Inclusão parcial e total de raspa de mandioca na porção energética de rações para caprinos.

A utilização de culturas adaptadas ou nativas ao semi-árido, como a silagem de maniçoba, a raspa de mandioca e o sorgo na alimentação animal poderia reduzir a deficiência alimentar dos rebanhos, elevar os índices de produtividade e conferir competitividade aos sistemas de produção animal. O bjetivo do presente estudo foi avaliar o desempenho de caprinos em crescimento alimentados com rações contendo silagem de Maniçoba e inclusões parciais e total de raspa de mandioca na porção energética do concentrado, usando a proporção de 80% de volumoso e 20% de concentrado, na matéria seca. Os tratamentos avaliados foram: raspa de mandioca, raspa de mandioca em associação com farelo de trigo e raspa de mandioca associada ao sorgo em grãos. Foram utilizados 18 caprinos machos com peso vivo inicial médio de 14,06±3,61 kg distribuídos em três grupos, mantidos em baias coletivas, cada baia com seis animais. O delineamento experimental adotado foi o inteiramente casualizado com seis repetições. Não foram observadas diferenças significativas (P>0,05) entre os tratamentos avaliados sobre os pesos vivos iniciais e finais, ganhos médios diários, ganhos de peso totais e escores de condição corporal inicial e final. As inclusões parciais e total da raspa de mandioca em rações para caprinos em crescimento alimentados com silagem de maniçoba foram tecnicamente viáveis. A opção de uso ficará por conta das vantagens econômicas de cada uma das estratégias avaliadas