Some structural and biochemical features of clematis plants in vitro

N.N. Ivanova, V.A. Brailko, O.A. Grebennikova, A.E. Paliy, N.V. Zubkova, I.V. Mitrofanova
The aim of our reseach was to identify some structural and biochemical features of improved clematis microshoots in cultivars ‘Alpinist’, ‘Nikitsky Rosovy’, ‘Madame Julia Correvon’ and ‘Crystal Fountain’ under in vitro conditions. Isolated sterile vegetative buds were cultured on MS medium supplemented with 0.5-0.7 mg L‑1 BAP and 0.1-0.3 mg L‑1 NAA. The results showed 3.8±0.7 normal shoots explant‑1 in ‘Nikitsky Rosovy’, 3.7±0.5 – in ‘Crystal Fountain’, 2.5±0.4 – in ‘Madame Julia Correvon’. The form of the leaf blades in regenerants retained cultivar characteristics of the original maternal plants. The leaf size was more cultivar-specific characteristic, leaf length varied from 0.5 to 1.7 cm, width – from 0.3 to 0.6 cm (the maximum size was noted in ‘Crystal Fountain’). The number of necrotic leaf blades was 5-48%, maximum in ‘Madame Julia Correvon’. The leaves were thin (from 83 to 182 µm thick), bifacial (palisade index 0.29-0.37), hypostomatic. Vascular bundles were closed collateral, stomatal apparatus was multiple (57-136 stomata mm‑2, stomatal pore length 28-51 μm), anomocyte type, slightly elevated above the cells of the epidermis or on a level with them. One-two-celled trichomes (up to 143 µm long, 2-16 trichomes mm‑2, maximum in ‘Crystal Fountain’) were noted. More than 60% stomata were open, that is typical for in vitro cultivars. Epidermal cells were of winding shape and irregular ameboid form. The assessment of assimilation processes revealed partial photoinhibition: the relative photosynthetic activity ((Fm-Fst)/Fm) = 0.48 ... 0.58 a.u.).
Ivanova, N.N., Brailko, V.A., Grebennikova, O.A., Paliy, A.E., Zubkova, N.V. and Mitrofanova, I.V. (2021). Some structural and biochemical features of clematis plants in vitro. Acta Hortic. 1324, 151-158
DOI: 10.17660/ActaHortic.2021.1324.23
Clematis L., vegetative buds, microshoot regeneration, leaf blades structure, photosynthetic activity

Acta Horticulturae