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The present document attempts to anylize the plant biotechnology situation in Eastern European Countries. Existing limitations, and new developments made in the practical applications of modern plant biotechnology in most Eastern European countries have been discussed Recommendations have been made to create a Plant Biotechnology Network for these countries, in order to promote the implementation of biotechnological tools, enhance communication among scientists, and coordinate efforts in order to improve the scientific development in this area. Particular emphasis has been put on FAO's role in providing assistance to facilitate the creation of the Network.

Apple is the most important fruit tree species, largely cultivated in the temperate zones of both world hemispheres. Although. possessing a comparatively high level genetic variation, due to easy intercrossing within the Malus genus, the spontaneous m•utation rate of apple is low. Successful efforts to induce mutations in vivo have resulted in the registration of 10 commercial varieties. However effective for increase of genetic mutation frequency, classical mutation breeding is a rather slow process. In vitro techniques present an alternative for overcoming problems related to long-life cycle, jouvenile period, chimaera formation, etc. As a result of the studies, relevant to this paper, we have established a reliable method for regeneration of adventitious shoots from leaf somatic tiss•ues of two important apple varieties, Prima and Granny Smith, in vitro. Up to 100% of the leaf explants of both varieties produced one or more regeneration events when cultured on Murachige and Skoog (3) basic medium supplemented with 5 mg/1 ben::ylaminopurine (BA P), 1 mg/1 naphtaleneacetic acid (NAA) and 1 mg/1 thidiazur•one (TDZ) with a 35 day pretreat111c11t in 24 It darkness, followed by expos•ure to 16 h photoperiod both performed at 25°± /° C. The values of the critical dose of irradiation with gamma rays of 6°C o, i.e. LD:Jo, for in vitro pmpagaled plants of both varieties were established. LD 30 values were obt>iously genotype dependent. The effect of gamma irradiation on a~ven titious shoot regeneration capacity wcr•e studied. It was dependent on growth r•egulator composition of shoot regeneration medium and genotype.