Molecular characterization of low-level vancomycin-resistant enterococci found in coastal water of Thermaikos Gulf, Northern Greece.

Enterococcus includes species that may pose emerging health risks and has been used as biomarkers for environmental contamination while little is known concerning their occurrence in marine water. Classification of enterococci in environmental samples can be problematic and requires polyphasic taxonomy. In this study, we investigated the presence of vancomycin-resistant enterococci (VRE) in the inner bay of Thermaikos Gulf in Northern Greece. Based on physiological and biochemical criteria, 121 presumptive enterococcal strains were identified. High-level VRE were undetectable in seawater and only 35 vancomycin gene-negative strains possessed low-level vancomycin resistance. Genotyping by pulsed field gel electrophoresis (PFGE) proved to be more reliable for marine enterococcal discrimination and revealed distinguished characteristics of the seawater enterococci, indicating high genetic diversity. Random amplified polymorphic DNA-PCR (RAPD-PCR) was unable to separate distinct species analyzed in this study. This study indicates the need of polyphasic taxonomy for seawater enterococcal species' identification and provides information for future biomonitoring programs of Thermaikos Gulf.

Multiple resistance of Botrytis cinerea from kiwifruit to SDHIs, QoIs and fungicides of other chemical groups.

BACKGROUND: Botrytis cinerea Pers.: Fr. is a high-risk pathogen for fungicide resistance development that has caused resistance problems on many crops throughout the world. This study investigated the fungicide sensitivity profile of isolates from kiwifruits originating from three Greek locations with different fungicide use histories. Sensitivity was measured by in vitro fungitoxicity tests on artificial nutrient media. RESULTS: Seventy-six single-spore isolates were tested for sensitivity to the SDHI fungicide boscalid, the QoI pyraclostrobin, the anilinopyrimidine cyprodinil, the hydroxyanilide fenhexamid, the phenylpyrrole fludioxonil, the dicarboxamide iprodione and the benzimidazole carbendazim. All isolates from Thessaloniki showed resistance to both boscalid and pyraclostrobin, while in the other two locations the fungal population was sensitive to these two fungicides. Sensitive isolates showed EC(50) values to boscalid and pyraclostrobin ranging from 0.9 to 5.2 and from 0.04 to 0.14 mg L(-1) respectively, while the resistant isolates showed EC(50) values higher than 50 mg L(-1) for boscalid and from 16 to > 50 mg L(-1) for pyraclostrobin. All QoI-resistant isolates carried the G143A mutation in cytb. Sensitivity determinations to the remaining fungicides revealed in total eight resistance phenotypes. No isolates were resistant to the fungicides fenhexamid and fludioxonil. CONCLUSION: This is the first report of B. cinerea field isolates with resistance to both boscalid and pyraclostrobin, and it strongly suggests that there may be a major problem in controlling this important pathogen on kiwifruit.

Description and analysis of genetic diversity among squash accessions

In this work, the part of the squash core collection, maintained in the Greek Gene Bank, was assessed using the morphological and molecular data. Sixteen incompletely classified accessions of the squash were characterized along with an evaluation of their resistance against two isolates of Fusarium oxysporum. A molecular analysis using Random Amplified Polymorphic DNA (RAPD) markers was also performed, revealing high level of polymorphism. To study the genetic diversity among the squash accessions, a clustering procedure using Unweighed Pair Group Method and Arithmetic Average (UPGMA) algorithm was also adopted. Two independent dendrograms, one for the morphophysiological and one for molecular data were obtained, classifying the accessions into two and three main clusters, respectively. Despite the different number of the clusters there were many similarities between these two dendrograms, and a third dendrogram resulting from their combination was also produced, based on Gower's distance and UPGMA clustering algorithm. In order to determine the optimal number of clusters, the upper tail approach was applied. The more reliable clustering of the accessions was accomplished using RAPD markers as well as the combination of the two different data sets, classifying the accessions into three significantly different groups. These groups corresponded to the three different cultivated species of C. maxima Duch., C. moschata Duch., and C. pepo L. The same results were also obtained using Principal Component Analysis.

A abobrinha de inverno compõe um cultivo agrícola com valor econômico determinado exercendo, no entanto, um papel importante em zonas caracterizadas por um cultivo menos intensivo. Na Grécia, o cultivo da abobrinha se baseia, principalmente, em variedades locais conservadas a muitos anos por agricultores locais. Uma parte do cultivo nuclear da abobrinha, que é conservada pelo Banco Grego de Genes, foi melhorada utilizando-se dados morfológicos e moleculares, especialmente dezesseis cultivos de abobrinha classificados incompletamente, que foram diferenciados apenas com base em características morfológicas, em relação a uma avaliação à resistência contra o Fusarium Oxysporum, em dois isolamentos. Foi realizada uma análise molecular utilizando DNA Polimórficos Casual Amplificados índices (RAPDs), revelando um alto nível de polimorfismo. Para estudar a diversidade genética entre a coleção de abobrinhas, um procedimento de agrupamento foi realizado usando-se o algoritmo U.P.G.M.A. Dois dendrogramas independentes, um morfofisiológico e outro para dados moleculares, foram coletados, classificando as coleções em dois e três grupos básicos, respectivamente. Apesar do número diferente dos grupos, foram introduzidas muitas semelhanças entre os dois dendrogramas e um terceiro dendrograma foi produzido como resultado da combinação dos dois primeiros, baseado na distância de Gower e no algoritmo de agrupamento U.P.G.M.A. Para determinar o número ótimo dos grupos, a aproximação "upper tail" foi aplicada. O grupo mais aceitável das coleções foi conseguido usando-se índices RAPD, assim como a combinação dos dois grupos de dados diferentes, classificando as coleções em três grupos consideravelmente diferentes. Os grupos que correspondem às três espécies cultivadas diferentemente, que correspondem às três espécies cultivadas diferentemente por C.máxima Duch., C.moschata Duch. e C. pepo L. além disso, os mesmos resultados foram conseguidos usando-se a "Principal...