Breeding of industrial hemp with a high content of cannabigerol by the case of ‘Vik 2020’ cultivar

Abstract

To create an industrial hemp variety of the Central European ecological and geographical type with a high cannabigerol content and universal application. Methods. Breeding (self-pollination, creation of artificial populations, selection), field, biochemical (thin-layer and gas-liquid chromatography of cannabinoid compounds), instrumental and technological assessment of fibre quality, and statistical methods. Results. Variety ‘Vik 2020’ was obtained as a result of creation of artificial populations. The plants are characterized by higher content of cannabigerol (1.034 ± 0.0323%), and almost zero of other secondary metabolites, such as cannabidivarin, cannabidiol, cannabichromene and psychotropic tetrahydrocannabinol (0.003 ± 0.0011; 0.018 ± 0.0080; 0.012 ± 0.0027, and 0.005 ± 0.0012%, respectively). The t rait of cannabigerol content is quite stable within the population and is not correlated with the trait of tetrahydrocannabinol content (r = -0.23). TLC showed that cannabigerol accumulated mainly in the form of cannabigerolic acid and to a lesser extent as a neutral compound, which is consistent with the theory that this substance is a precursor for the synthesis of other cannabinoids. According to the results of the competitive variety test, when growing to obtain fibre and seeds, the variety features short height, specifically significantly lower total (206.4 cm) and technical stem length (135.6 cm) compared to the standard variety, significantly higher inflorescence length (70.8 cm), which determine the formation of the significant yield of biomass suitable for pharmaceutical use and high seed yield (0.98 t/ha). The yield of total fibre was the same as in the standard variety (29.0%), but its quality and technological value for primary processing were higher. The variety had a homogeneous sex structure, resistance to bioltic and abiotic environmental factors. Plants reached biological maturity in 116 days (BBCH 89). This cultivar is recommended for obtaining seeds, quality fiber and potentially cannabigerol (on condition of changes in legislation). Conclusions. The efficiency of using self-pollinating lines in breeding with their subsequent combining into a synthetic population and improving selection was proved by the case of a new variety of industrial hemp ‘Vik 2020’, characterized by an increased content of cannabigerol and the absence of psychotropic properties