B. Papp szerk.: Studia Botanica Hungarica 29. 1998 (Budapest, 1999)

Vasas, Gizella, Bohus, Gábor; Locsmándi, Csaba: Genetic resource collection of macrofungi in Hungary

The (biodiversity) conservational purpose genetic resource collections are very important also for the basic and applied research. From the isolates of type strains the given fungus species is reproducable at any time. These can be very important if genetic damages or mutations happened in a cultivated strain. In these cases the cryopreserved strains of the original gene pool are crucial. Genetically similar strains can be crossed and selected. The new hybrid or selected species or strains can be introduced into cultivation. The genetic resource collections can also supply several saprophytic strains containing anticarcinogenic, colesterine level reducing or antiviral substances useful for medical treatments. The number and size of the genetic resource collections became more extensive throughout the world in the last years (LOCSMÁNDI 1992). In Hungary there is only one cryopreserved genetic resource collection of macrofungi in the Macrofungi Collection of the Hungarian Natural History Museum, in Budapest, where in addition to the 191 isolates of cultivated or potencially cultivable mushrooms, 142 strains of rare, endangered or characteristic Hungarian species are found (VASAS et al. 1998) (Table 1). The technical development of cryopreservation and the foundation of the genetic resource collection storing in liquid nitrogen started here in 1991 with the financial support of the Hungarian Scientific Research Fund (OTKA No. 3187). The maintenance and the gradual enlargement of the collection since then have been further sponsored by the Hungarian Scientific Research Fund (OTKA No. 17767). TRADITIONAL MAINTENANCE OF MYCELIUM CULTURES The traditional method, the maintenance of isolates by periodic transfers on solid medium at room temperature, has several disadvantages. The cultures must be transferred quite frequently, 3-6 monthly after the substrate colonization, because of the senescence of the mycelium and the drying up of the medium. At lower storing temperature (2-5 °C) this time period can be extended up to 6-12 months. The cultures might be infected by microorganisms (bacteria, moulds etc.) during the isolation, incubation or storing. Morphological properties of the mycelium might change after a longer period, the growth rate, the yield rate, and the yielding capacity might decrease considerably. Also, transfers of the isolates take up much work. The traditional culture collection in the Hungarian Natural History Museum was founded by Gábor Bohus in the 1950s. The first pure cultures were prepared from various Agaricus bisporus strains. Involving these strains in cultivation, the Hungarian yielding rates increased considerably. Other strains of xylophagous species were very useful in testing fungicidal substances in case of wood de-