© iForest -Biogeosciences and Forestry IntroductionAsh dieback is an emerging fungal disease caused by the ascomycete Hymenoscyphus pseudoalbidus Queloz et al. (2011), anamorph Chalara fraxinea Kowalski (2006). This highly pathogenic fungus was most likely introduced from the Far East (Zhao et al. 2012). The first symptoms of the disease were observed in Poland in 1992, and since the pathogen has spread throughout Europe (Timmermann et al. 2011, Pautasso et al. 2013. Common ash (Fraxinus excelsior L.) and narrow-leaved ash (F. angustifolia Vahl.) are European ash species the most heavily affected by the pathogen (Kirisits et al. 2009, Gross et al. 2014, although some introduced ash species could also be attacked (Drenkhan & Hanso 2010).Control of the ash dieback is hardly possible in areas where the disease is already established (Gross et al. 2014). However, proper control measures should still be taken to prevent or at least to slow down further spread of the pathogen (Pautasso et al. 2013), or to eradicate the pathogen at locations where this is still possible (relatively small, spatially limited and recently infected areas). Furthermore, the protection of individual high-value ash trees should also be often provided. Chemical treatment may be one of the options in some cases, but data on effective chemical agents for control of the ash dieback pathogen are lacking.Ascospores that develop in apothecia on infected ash leaf debris from the previous year are the major source of new infections (Gross et al. 2012(Gross et al. , 2014. Leaf debris from the previous year represents an inoculum source for some other well-known tree diseases. Good examples are cherry leaf spot caused by Blumeriella jaapii (Rehm) Arx and apple scab caused by Venturia inaequalis (Cook) Wint. For control of both mentioned diseases, urea treatments of the infected leaves are used to reduce pathogen sporulation (Sutton et al. 2000. Thus, removal of the infected ash leaf debris (if possible) or treatment of the debris to prevent sporulation of H. pseudoalbidus could therefore be regarded as potential control measures (Cooke et al. 2013).The main aim of this study was to examine the effect of eight different fungicides that are effective against different pathogens of the Helotiales order as well as the effect of urea on mycelial growth in Petri plates and development of H. pseudoalbidus apothecia on fallen ash leaf petioles. Materials and Methods H. pseudoalbidus isolates used in testingFour Slovenian isolates of Hymenoscyphus pseudoalbidus were used in this study (Tab. 1). Isolates were previously obtained from necrotic F. excelsior wood samples and stored in the culture collection of the Laboratory for Forest Protection at the Slovenian Forestry Institute (ZLVG). The selected isolates were of different morphology in culture and represented different geographical regions of the country. Three weeks before treatment experiments (preliminary testing was planned on July 13 th , 2010, and the main testing on August 26 th , 2010), all four is...

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This four-year study reports the occurrence of ergot alkaloids (EAs) in cereals intended for animal feeding collected in Slovenia. A total of 517 samples of cereals were analysed using liquid chromatography-tandem mass spectrometry for the presence of EAs. The sample set included wheat, rye, triticale, oat, spelt and barley. The study revealed that 17% of the analysed cereal samples were contaminated with at least one ergot alkaloid. EAs have two epimeric forms: -ine and -inine. The incidence rates of the -ine and -inine forms in the analysed samples were 16% and 15%, respectively. The highest contamination rates were observed in rye (54%), oat (50%) and spelt (30%), where the highest mean concentrations of total EAs were also determined (502 µg/kg, 594 µg/kg and 715 µg/kg, respectively). However, the highest concentrations of total EAs were found in wheat and rye (4217 µg/kg and 4114 µg/kg, respectively). The predominant EAs were ergometrine, ergosine and ergocristinine. The occurrence of six or more ergot alkaloids was observed in 49% of the positive samples. A weak correlation (p = 0.284) in the positive samples was found between the mass of sclerotia and the total concentrations of EAs using the Spearman correlation coefficient.

We analyzed with an amplified fragment length polymorphism (AFLP) marker system the genetic diversity and relationships among 67 Monilinia laxa isolates obtained from different host plants. From a total of 1,089 amplified bands scored using 20 primer combinations with two selective nucleotides, 354 were polymorphic and further used in genetic diversity analysis. Genetic relationships among isolates were assessed with different phenetic approaches, including unweighted pair group method with arithmetic mean clustering and principal coordinate analysis; the population's differentiation estimate was analyzed by molecular variance; and model-based clustering was employed to infer population structure. All four analyses clearly showed significant differences between isolates from apple trees and isolates from other host plants. No further grouping according to any other host plant was observed. The results indicate host specialization of apple isolates and support the taxonomic grouping of apple isolates.

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