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  • The microscopic fungi of orchid species in the Őrség National Park
    31-36.
    Views:
    164

    The wild orchids growing in Hungary are some of the most decorative and interesting members of the country's flora. The majority of species are rarely spotted, and some are only found in very few habitats, though others are quite common .All the species known in Hungary are protected, and 1 1 species are strictly protected. Itis thus important to monitor the health status of these plants, to determine what diseases affect them, what pathogens are found on them and how severely they are infected, and to take the necessary precautionary measures. Eleven of the 14 orchid species occurring in the 6rseg National Park were included in the study and the presence of microscopic fungi was detected on eight of these. Pathogenic species were found on lesser butterfly orchid (Platanthera bifolia), green-winged orchid (Orchis morio), burnt orchid (Orchis ustulara), sword-leaved helleborine (Cephalanthera longifolia), common twayblade (Listera ovata), autumn lady's-tresses (Spiranthes spiralis), western marsh orchid (Dacrylorhiza majalis) and broad-leaved helleborine (Epipactis helleborine). A detailed account is given of the symptoms of major diseases and of the microscopic traits of the pathogens. An attempt was made to determine to what extent the pathogenic fungal species found on protected orchid species influence the lives of these plants. Current knowledge on this subject is extremely deficient, as practically no data are available from Hungary.

  • The evaluation of grape vine decline pathogens in the experimental field of the Georgikon Faculty of Agriculture in Cserszegtomaj
    19-22.
    Views:
    155

    Vine decline causes important economic loss in viticulture, especially in longer view. Several causal pathogen were described lately, however little is known about the etiology or epidemiology of these pathogens on grapevine rootstock. It is well known that these diseases affect grafted and rooted grapevines and are not specific to any scion-rootstock combinations. Our aim was to determine what pathogens are presents in the experimental field, especially causal agents of the rootstock decline. Different grapevine rootstocks and scion varieties were tested in our trial. Isolations were made from the wood tissue and pathogenity tests were done with isolated Cylindrocarpon destructans. The possibility of infection during the propagation process was studied as well. Most commonly Cylindrocarpon sp. and Phomopsis sp. species were identified from the examined varieties. Cylindrocarpon destructans was able to spread to apical (shoot) and basal (root) direction from the point of infection with uneven speed. Callus development is not inhibited by the fungi causing the leaf symptom of the vine decline. Shoot development is reduced if unhealthy parts are grafted to each other.