The purpose of the research was the introduction of hazelnut (Corylus avellana L.) in order to obtain uncontaminated, high-quality planting material in a relatively short time. The research was carried out in the Embryology and Biotechnology Laboratory of the "Alexandru Ciubotaru" National Botanical Garden (Institute) of the USM. According to specialized literature, the initiation of in vitro culture for Corylus avellana L is difficult due to a number of reasons: the high degree of bacterial and fungal contamination, the oxidation of explant tissues, the excess of phenols and the explant necrosis following the action of the substances used for asepsis. In the previous years for the inoculation of Corylus avellana L. in in vitro culture, several variants of asepsis the explants were tested, but the percentage of infested and necrotic inoculum was high, because the plant material was collected from the plantations, but according to the specialized literature for for the inoculation to proceed successfully, it is necessary that the donor plants are kept in the greenhouse, or protected land and that the treatment with fungicidal preparations is carried out beforehand. The donor plants from which the explants were taken were processed with the preparation Tank 70 WP, which contains methyl thiophanate and is a systemic fungicide. After 7 days, the biological material was taken, portions of shoots with apical buds were used as explants. The collected biological material was washed according to the protocol developed in the laboratory. After that, the explants were disinfected with a 0,1% diacid solution for 5 minutes and modeled in a laminated air flow, being inoculated on agarized nutrient medium, one inoculum in a test tube. After treating the donor plants with the fungicide preparation and sanitizing with 0,1% diacid for 5 minutes, we obtained about 50-60% viable inoculums. Following the research we have determined that the preliminary treatment with the preparation Tank 70 WP and sterilization with 0,1% diacid for 5 minutes significantly increases the chance of obtaining viable inoculums, subsequently applied for the microcloning process.