The research addressed the effect of gibberellic acid (GA 3 ) on growth and flowering of Ajania pacifica /Nakai/ Bremer et Humphries 'Bea'. The vegetative growth lasted for 8 weeks in glasshouse, under natural long day and from August 15 -under natural short day. The plants were divided into four groups: 1 -the plants sprayed with distilled water (control combination); 2, 3 and 4 -the plants sprayed with GA 3 ones, twice and thrice, respectively, starting from the 5 th week of growth, and then in the 6 th and 7 th week, successively. Each of the group was divided into two subgroups: the first one treated with GA 3 at concentration of 250 mg·dm -3 and the second with 500 mg·dm -3 . It was observed that double spraying with GA 3 accelerated the buds development of Ajania pacifica, thus shortened the cultivation time by about two days. Treatment with GA 3 at concentration 500 mg·dm -3 stimulated the elongation of shoots more than treatment with GA 3 at 250 mg·dm -3 . The plants sprayed twice were longer than the control and then those sprayed one time. However, elongation of shoots was not remarkable; corymbs were shorter, narrower, and contained lesser number of inflorescences. The present study indicates the specificity of the response of Ajania pacifica to GA 3 treatment, which appears to be different from other ornamental species.

This study tested the effects of explant type, medium composition, and cultivar on in vitro regeneration of callus, shoots, and roots in Ajania pacifica (Nakai) Bremer et Humphries. In Experiment 1, "Bea", "Bess" and "Bengo" ex vitro internodes and ex vitro leaf explants were inoculated on a modified MS (Murashige and Skoog, 1962) medium with 3 mg @ dm !3 benzylaminopurine (BAP) and 0.5 mg @ dm !3 indole-3-acetic acid (IAA). The share of internodes and leaf explants that proliferated callus were 92-96% and 56-100%, respectively. Adventitious shoot regeneration was observed on "Bengo" and "Bea" internodes (1.12 and 0.32 shoots, respectively, per explant inoculated) and on "Bea" leaf explants (0.2 shoots per explant inoculated). In Experiment 2, "Silver and Gold" ex vitro leaf explants were placed on a modified MS medium with the addition of auxin and cytokinin: 0, 0.5, and 1 mg @ dm !3 1-naphthaleneacetic acid (NAA) or thidiazuron (TDZ) or BAP. Callogenesis was not reported only in the medium without plant growth regulators. Adventitious roots were seen to regenerate on media without plant growth regulators and with 0.5 or 1 mg @ dm !3 NAA (0.47, 1.2, and 2.93 roots per explant inoculated, respectively). In Experiment 3, "Bea", "Bess" and "Bengo" ex vivo internodes were inoculated on a modified MS medium with 0.6 mg @ dm !3 BAP and 2 mg @ dm !3 IAA. All explants produced calli. Shoots regenerated only on "Bengo" internodes (1.3 shoots per explant inoculated). These results confirmed the possibility of in vitro callogenesis and adventitious organogenesis in Ajania pacifica.

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