EN
Ripe, stratified beechnuts, turned out to be almost impossible to sterilize employing the commonly used sterilizers. The recommended way of sterilizing beech nuts is to soak (for 5 minutes, in a 2% solution of NaOCl) the embryos with parts of cotyledons, isolated from nuts partly sterilized with an 15% solution of NaOCl for 15 minutes. The chloraminę (concentration 4%, time of soaking 2 minutes) provided 100% sterility of the fragments of epicotyles and buds; it also increased up to 80% the effectiveness of the sterilization of cotyledons of beech seedlings. The only way to obtain the required effectiveness of sterilization of buds collected in winter from 20-year old trees turned out to be soaking in HgCl2; its concentration and time of exploit soaking can be reduced in comparison to those proposed by Chalupa (1985a), namely from 0.1-0.3% and 15-30 minutes down to 0.05% and 30 seconds.