Zs. P. Komáromy szerk.: Studia Botanica Hungarica 15. 1981 (Budapest, 1981)

Bohus, Gábor: Some results of systematical and ecological research on Agaricales, VIII

do not fructificate at all, or some of them take part in fructification if the favourable conditions last. In this respect we succeeded in carrying out experimental observations with a prairiespecies, Agaricus macrosporoides. The thoroughly mixed culture medium was divided into a number of culture vessels and sterilized in a special autoclave (the circumstances are homogenous). Inoculation was carried out from one inoculum (spawn) onto the surface of the culture medium; in some cases, 5-8% of the small sized spawn were mixed with the culture medium. In this last case a great number of mycelium thalli were produced during the period of interlace - thalli were started from several points of the medium and posses different growth intensity - the intensity differences become eliminated and the culture medium was fully interlaced. The parallel cultures were kept in a thermostate at 25 C during the period of interlace, then the cultures were placed in a thermostat at 16-18 C during the fructification period. The fruit bodies appeared in 21% of the cultures approximately at the same time; the appearance of the fruit bodies took place in some cases at other time, sometimes it takes long time. Rarely it also was observed that one of the parallel cultures did not produce fruit body at all (Table 1). On the basis of these observations, it can be supposed, that the dispersion of fructification in time is considerable, and it is possible that this is characteristic for other species, too. A further observation: IMREH (1969) carried out observations for decades in connection with fruit body formation of another prairie species, Agaricus maskae, about on 260 mycelium thalli. He found, that some 10 days after a substantial rainfall there occurred many fruit bodies but certain fairy-rings - next to the fructifying mycelium thalli - did not fructificate at all, or rarely produced fruit bodies. This observation was made possible by the fact that, by discolouring of grasses the boundary of the mycelium thalli is well visible even if the fungus does not produce any fruit body in the given case. Since the soil in these examined pastures is rather homogeneous, it has no mosaic pattern, so it is impossible that the différencies, observed in fructification, could be caused by soil factor. The observation related to Agaricus maskae, seems to be a reliable one. Table 1. Harvesting time of the first fruit bodies Date and method of inoculation Number of days from the beginning of ^production period in Date and method of inoculation 1st 2nd parallel culture 3rd 1970 . XX A 6.IV. . XX A 10 25 31 U.V. A 22 22 38 io.vm. A 3 17 17. IX. A 6 16 37 14.XI. A 16 18 18 1971 4.1. A 18 21 31 16.11. A 18 31 24.

m. A 26 30 1972 4.n. A 15 16 11.11. A 15 17 3i.m. A 21 22 28.VI. A 34 38 18. XII. A 14 26 Date and method of inoculation Number of days from the beginning of^production period in Date and method of inoculation 1st 2nd parallel culture 3rd 1973 22.1. A 37 50 7.rv. A 15 17 9.V. A 15 15 15 31.

V. A 17. 31 34 4.VI. A 34 44 46 26.VI. A 14 14 15 13. VII. A 27 29 32 11.

X. A 20 34 24.X. A 19 19 30 1974 17.1. A 14 28 22.1. A 16 38 23.1. A 15 36 25.1. A 23 38 31.1. A 24 27 35 14.11. A 19 22