In order to elucidate effects of 24 epibrassinolide (EB) on the efficiency of in vitro regeneration of highbush blueberry (Vaccinium corymbosum L., cv. Brigitta blue), we analyzed variability of seven biopro ductive parameters in regenerant plants cultured on nutrient media differing in hormonal composition. The additive action of EB, cytokinin (2iP), and auxin (IAA) was discovered for several parameters, such as repro duction coefficient, weight of regenerant plants, and the content of anthocyanin pigments. The greatest reproduction coefficients were noted in regenerant plants cultured on the medium containing 0.25 mg/L EB, 7.25 mg/L 2iP, and 1.00 mg/L IAA, as well as on the medium with 0.05 mg/L EB, 2.00 mg/L 2iP, and 0.50 mg/L IAA. It is suggested that low concentrations of 2iP and EB, applied in certain combinations, can be used for the industrial in vitro propagation of regenerant plants of highbush blueberry varieties.Abbreviations: 2iP-6 (γ,γ dimethylallylamino)purine; BSbrassinosteroids; EB-24 epibrassinolide; GA-genuine antho cyanins; LA-leucoanthocyanins; RC E -reproduction coeffi cient for explants; RC S -reproduction coefficient for shoots; TAP-total content of anthocyanin pigments; WPM-nutrient woody plant medium.

Twenty-eight hybrids were generated by crossing seven male sterile lines with four restorers in the line × tester cross system. GCA and SCA effects of parental lines and heterosis effect of F 1 hybrids have been evaluated for 4 characters. Two of the twenty-eight Byelorussian hybrids (Donskoy 22 and Signal) revealed higher values for oil yield with respect to standard checks. According to the data obtained it is quite possible to produce prospective Byelorussian hybrids under local soil-climatic conditions.

Thus, as a result of biochemical screening of 30 taxons of Ericaceae species taking into account 32 parameters in a long-term cycle of observation it has been established the different degree of dependence of variability level of biochemical structure components of fruits of alien crops on genotype and a hydrothermal mode of the period of their maturing has been revealed. The similarity of parameters of genotypic variability of some traits of all investigated Ericaceae species is also revealed: low one – for the general contents in fruits of soluble sugars, flavonols, of potassium, calcium, magnesium and high one – for the contents of anthocyanins, and also the ratio of fractions of pectinaceous substances and bioflavonoids. Specific features of genetic determinacy of the analyzed traits, testifying the greatest degree of its displays of V. corymbosum for total accumulation of soluble sugars and bioflavonoids, flavonols contents, calcium and magnesium and by the lowest degree – for the contents of titratable acids, vitamin C, anthocyanins and values of a sugar-acid index were established. If to mention V. vitis-idaea L., the parameters of general accumulation in fruits of soluble sugars, dry substances and all major mineral elements were characterized by the greatest degree of genetic determinacy, whereas by the least degree – the contents of anthocyanins, catechines and tannins. If to mention V. macrocarpon, the parameters of accumulation in fruits of dry substances, nitrogen, potassium, calcium, phenol-carboxylic acids have been noted by the most expressed genetic determinacy, and by the least expressed – the contents of anthocyanins, sucrose and pectinaceous substances in fruits.

The article presents the results of studies on the comparative analysis of bioproductional parameters of plant growth of Bluecrop and Elizabeth high-bush blueberry ex vitro under the conditions of fluorescent and LED lighting. Ensuring the optimal spectral composition of radiation, realized with the original LED light, led to a significant increase at 1.1–1.6 times in all of the analyzed growth parameters in high-bush blueberry ex vitro plants.