INSTYTUT DENDROLOGII

Investigations concerning a new method against pathogenic species of fungi on acorns of Pedunculate oak and on seeds of European beech, increasing of the frost resistance of acorns by hardening as well as the acceleration and standardization of the emergence of oak seedlings grown in containers were the basic aims of the presented Ph.D. thesis.

During the investigations a positive influence of the applied various fungicides (8 for oak and 13 for beech) on germination of seeds has not been confirmed.

A new method of thermotherapy of acorns in warm and humid air and that of beechnuts in warm water was presented. In both cases a positive effect of this measures on seedling emergence was proved.

The possibility of an increase of frost resistance of acorns was investigated. Freshly collected acorns are very sensitive to low temperature. It was found that during storage the gradual decrease of temperature causes the frost resistance of acorns to increase even to -15°C for a short time.

Rentability of the production of seedlings of oak in containers is seriously reduced in consequence of the prolonged germination of seeds and seedling emergence. These processes can be significantly accelerated by sowing into containers acorns deprived of about 1/3 of their original length by cutting off the apical ends of their cotyledons. The mean germination time is shortened from about 8 to 4 weeks.