## 3 Results and Discussion
### In Vitro Culture Analysis
Various combinations of BAP and NAA in the MS medium were also investigated by [PERSON] et al. [42] in _Scutellaria brevibraceta_ subsp. _subvelutina_. These authors concluded that BAP concentrations in a range of 0.5-3 mg/dm\({}^{3}\) in combination with NAA did not result in statistically significant differences in both fresh and dry biomass. According to [PERSON] et al. [43], high efficiency in shoot formation through callus tissue could be achieved but only when it was obtained in media containing NAA in combination with KIN or BAP at a concentration of 0.5 or 1.0 mg/dm\({}^{3}\). The results of our study partially confirmed this observation, with respect to the MS + BAP medium at all concentrations, where indirect shoot organogenesis was observed (as an effect of BAP alone), while they were contradictory in relation to the MS + KIN medium. The reason for these discrepancies could be the interaction of the applied PGRs with the components of the medium, as pointed out by [PERSON] et al. [44]. In addition, it is necessary to consider the interactions between the genotype, type, and PGR concentration, as postulated by [PERSON] [45] and confirmed by the results of [PERSON] et al. [46], where shoot organogenesis through the callus stage allowed for obtaining a very high number of shoots, reaching up to 18 per explant in _S. araxensis_, and for the species we studied, _S. bialcensis_, the maximum was 5.8. At the same time, it is worth noting that different skullcap species, i.e., _Scutellaria anaxensis_[18], _Scutellaria bialcensis_[20], _Scutellaria bornmuelleri_[46], and _Scutellaria orientalis_ subsp. _bicolor_[14], exhibited a similar response to the applied MS medium without phytohormones. In the presence of this medium, there was no callus tissue formation, which was also observed in the present study. Considering the mean number of nodes, it should be noted that this feature reached the highest value on the MS + BAP 0.25 (6.0) medium and the lowest on the MS + KIN 0.25 (2.1) medium. The values of this feature are strictly dependent on the length of the shoot, which, for the above-mentioned media combinations,were 50.0 and 13.1 mm, respectively. On the MS + BAP 2 medium, few shoots up to 5.0 mm long and very numerous shoot buds were observed, which were not able to regenerate the shoot during the test, and the mean number of nodes per shoot could not be assessed. In the work of [PERSON] [47], the length of regenerated shoots ranged from 2 to 4 cm after 6 weeks of culture, depending on the medium applied. In the case of culture multiplication, the number of explants used to establish it is important. It may be high only in the case of the regeneration of a large number of shoots per explant as well as a large number of nodes per shoot. Achieving this goal is possible due to the highly positive correlation between these characteristics (0.97--Table 4). Therefore, based on the conducted research, the MS + KIN 2 medium should be considered the most optimal for the cloning process (direct organogenesis). However, in order to obtain differentiated material in the indirect organogenesis process, the MS + BAP 0.25 medium should be considered the best. In the analysis of the correlation coefficient for the analyzed characteristics, the positive impact of the formation of callus tissue on both the number of shoots per explant (0.71) and the mass of regenerants (0.78) should be distinguished. The correlation coefficient values between the remaining characteristics turned out to be statistically insignificant.