B. Papp szerk.: Studia Botanica Hungarica 34. 2003 (Budapest, 2003)

Vasas, Gizella: Investigations on macrofungi production effected by fungistasis at Pilisszentkereszt (Hungary)

Studia bot. hung. 34, pp. 19-26. 2003 INVESTIGATIONS ON MACROFUNGI PRODUCTION EFFECTED BY FUNGISTASIS AT PILISSZENTKERESZT (HUNGARY) G. VASAS Department of Botany, Hungarian Natural History Museum H-1476 Budapest, Pf. 222, Hungary; E-mail: vasas@bot.nhmus.hu Fungistasis of bacterial origin was studied by fungal production in Bacillus subtilis treated and control sites among natural conditions over three years. It was established that in the treated site the primary decomposer and the mycorrhizal fungi show no considerable difference in the number of fruitbodies compared to the controls. However, the numbers of species and fruit-bodies greatly increased. According to one of the possible reasons Bacillus subtilis starts the decomposing process, makes nutrients more easily available for secondary decomposers. Another possibility that Bacillus subtilis produces such fungistatic substances which inhibit or slow down the growth of the competitor organisms, while this effect is weaker on macrofungi. Key words: Bacillus subtilis, fungistasis, fruit-body, macrofungi, production INTRODUCTION Under natural conditions macrofungi are in continuous interaction with several other groups of living organisms. This fact is clearly demonstrated by the changes of several developing parameters of a macrofungi which was taken into sterile culture. Growth is usually accelerated, since nutrient sources are more abundant in the lack of competition with other species. The external conditions (temperature, humidity, etc.) are also possible to be optimalised. In case of fruit-body formation the correlation is not so clear. Most of the wood decaying fungi are able to produce fruit-bodies also under sterile conditions. In the case of mycorrhizal species the growth of mycelium is extremely slow and fruit-bodies have never formed so far. Neither terricolous saprotrophic fungi are able to produce fruit-bodies in culture, even if the growth of the mycelium remains at an acceptable level (VASAS et al. 1997). During the establishment and development of the mycological culture collection of the Hungarian Natural History Museum several thousands isolates were originated mainly from fruit-bodies (VASAS et al. 1998). Bacterial infections obviously started from the pieces of fruit-bodies were detected most of all at cultures isolated from secondarily saprotrophic and mycorrhizal species. The overwhelming majority of these infections was due to the presence of Bacillus and Pseudomonas species (Cs. LOCSMÁNDI pers. comm.). These species presumably effect pro-