Morphogenesis of roots and shoots in Gentiana pneumonanthe L. tissue culture

摘要

Gentiana L. species provide an advantageous model to study the details of morphogenesis events. They are suitable for in vitro culturing to generate cell line-producers of valuable biologically active substances. Aim of the work was to specify conditions for organogenesis from the G. pneumonanthe L. calli obtained earlier. Methods. As a starting material were taken tissue cultures of root origin derived from the G. pneumonanthe two population plants (Koryukivs'ke forestry, Chernigiv region – at the 9~(th) passage and v. Vygoda, Ivano-Frankivs'k region – at the 9~(th) and 19~(th) passages). To induce regeneration, we used MS medium as a basic one and supplemented it with combinations of phytohormones of diffrent concentrations: thidiazuron (TDZ) (1, 5, 10, 20 mg/1) and naphthylacetic acid (NAA) (0.01; 0.1; 0.2; 0.5; 1 mg/1). The nutrient medium MS with addition of 10 mg/1 TDZ and 1 mg/1 NAA was optimal for induction of the organogenesis. Results. Following two passages of the G. pneumonanthe calli culturing, the regeneration centers were formed upon illumination and at the end of the 3~(rd) passage root and shoot were regenerated. Intensity of organogenesis depended also on the original plant genotype. In particular, comparison of the G. pneumonanthe calli of the same age (the 9~(th) passage), but different in their origin, revealed that root number per explant (upon the same percent of rhizogenesis) in the tissue culture derived from Vygods'ka population plants was 21.7 root/expl., exceeding by 2.3 times this index (9.3 root/expl.) for the calli derived from other population plants (Koryukivs'ke forestry). The percentage of root and shoot regeneration in these two cultures was practically the same (17.4 % i 16.7 %, respectively), whereas shoot number per explant in the calli from Koryukivs'ka population plant was twice as much. The G. pneumonanthe callus capacity for organogenesis varied with growth duration. Conclusions. In particular, it was demonstrated that during cultivation of the G. pneumonanthe callus (v. Vygoda) from the 9~(th) to 19~(th) passage, the index of total regenerants number (roots and shoots) per explant decreased from 22 to 7 per/expl. This species showed rhizogenesis efficiency higher by one order of magnitude (in one case – even by two orders) than shoot organogenesis. Thus, G. pneumonanthe species exhibits high potential for shoot and root regeneration in tissue culture. An optimal for induction of organogenesis was nutrient medium MS, with addition of 10 mg/1 TDZ and 1 mg/1 NAA. The intensity of organogenesis depended on both genotype of original plant and duration of callus maintenance.