The object of investigation: proving of the breeding methods on elimination of tetrahydrocannabinol (THC), stabilization of the sign of monoeciousness and increasing of hemp productivity with the aim of creation of new breeding material. Aim of work: to set regularities of adjusting and fixing of homozygosity level of population of monoecious hemp by the signs of absence of THC, stabilizing of monoeciousness in the process of reproduction without decreasing of economic value of culture, ways of increase of the productivity of hemp varieties and on this basis to create hemp varieties. Methods: common scientific, field, biometrical, laboratory, statistical. Novelty: on the basis of revealed biological specialties of new hemp varieties with low cannabinoids content ways of control and fixing of recessive sign of THC absence are created. In difference of earlier breeding on increasing of cannabinoids content on the example of variety Viktoria for the first time the high effectiveness of use of improved methods of analysis, evaluation and selection in strict sequence is proved: plant-family-population. Firstly in the world the highest level of of homozygosis of the population of Viktoria variety by the sign of TNC absence of 98,0 - 99,2 plants is reached. Firstly it was revealed the population variability of monoecious hemp of Hliana variety with increasing of concentration of regressive genes of monoeciousness, intending of sexual polymorphism to the only sexual type - monoecious feminized pistillate hemp with ratio of male and female flowers in inflorescence as 10:90%. Also there were firstly established ways of increasing of stabilization of monoecious sign from lower step to the highest one. It5 was proved that the mechanism of increasing of stability of monoecious sign is realized in reverse way than in breeding on decreasing of cannabinoids cont5ent: population-family-plant. Results: For the breeding practice improved methods of fixing of monoeciousness, cannabinoids elimination and increasing of hemp productivity are proposed. New ways of revealing of perspective initial material in early phases which are directed on fiber content, seeds productivity, fast-ripening are created. New hemp varieties Viktoria, Hliana, Hlukhivski 66, Hlera, Hlesia, Hlukhivski 33, Hlukhivski 46, Hlukhivski 51 and hybrid Nasinnevyi are created. Degree of introduction: Varieties Hliana (2007) and Viktoria (2011) are registered in the State Register of Plants Varieties, which are suitable for spreading in Ukraine. Till 2012 Hliana variety is registered in State Register of Breeding Achievements of Russia. Hlera variety is investigated with future it's registration in France. Sphere of introuction: scientific institutions of NAS and NAAS of Ukraine, agricultural enterprises of whole forms of property of AIC of Ukraine.
