Zs. P. Komáromy szerk.: Studia Botanica Hungarica 16. 1982 (Budapest, 1982)
Bohus, Gábor: Some results of systematical and ecological research on Agaricales, IX.
Table 1. The effect of rising sodium sulphate concentration on the growth of the mycelia and the fructification Percentage of sodium sulphate Extent of mycelium intrusion 90 day' s crop related to the in the culture media into the culture media on the dry matter weight of the cul35th day ture media 4.5 cm 103% 3.5 cm 3.0 cm Agaricus bernardii In the case of this species no "in vitro" fruit body formation could be attained, therefore the effect of the treatment was only examined in the vegetative phase. It could be stated that 1% sodium sulphate in the culture media caused some inhibitory effect: the growth rate of mycelium was reduced by 1/3 (similarly as in Agaricus macrosporoides) . Agaricus flssuratus In the case of this species, too, only the effect on the vegetative phase could be examined. It can be detected that 1% sodium sulphate moderately inhibits. The growth rate of mycelium was reduced to some one half of its usual rate. Agaricus bisporus control 1% sodium sulphate in the culture medium causes full inhibition. On the 25th day after inoculation, the inoculation material did not even become pubescent, while in the culture without sodium sulphate, the interlacing was already in progress. This examination demonstrated the sensitivity of this species - not living on saline ground - to sodium sulphate, well. On the basis of in vitro examinations it may be stated that temporary decrease of salt concentration during rainy weather may be an impulse among the factors which act upon fructification during the favourable rainy weather. It is just possible that fungus species living on saline soils "are not fond of salts; they only tolerate the higher salts concentration. In consequence of this ability they can live on moderately saline areas from which, however, the species more sensitive to higher salt concentration are ousted. In the case of Agaricus bernardii, which is well known as living in saline soils, and which is very common in saline soils in Hungary, the location of the thalli could be well observed in the field. It is more frequent on those parts of Achilleo-Festucetum pseudovinae and A r t e m i si on - Fe stuc e tum pseudovinae associations where Festuca pseudovina is dominant. Its fairy rings of great size can be seen well - because of fading of Festuca pseudovina - even at a time when the thallus temporarily does not form fruit bodies. At the levels a few cm lower (see Fig. 3) no Agaricus bernardii fruit bodies were found in the Camphorosmetum annuae and Puccinellietum limosae associations. In the areas flooded with water for longer periods, on the saline plains of higher salt concentration, on the "blind saline soils", the fairy rings are interrupted . 0.5 1.0 1.5
