Some histological and physiological features of meristemoids formation in canna lily (Canna × hybrida hort.)

I.V. Mitrofanova, T.N. Kuzmina, V.A. Brailko
In vitro culture of canna lily (Canna × hybrida hort.) microshoots resulted in obtaining meristemoid clusters at their base that greatly improved the efficiency of micropropagation. Meristemoid cluster of canna lily was presented with dichotomous branched mass of parenchyma cells. In the mass of parenchyma cells, sections of vascular elements formation could be observed in various stages of their development: from petty areas of small cells with dense cytoplasm to branched vessels with spiral perforation, occupying a significant portion of the cluster. In the peripheral region of the cluster active meristematic areas were noted. Those areas were involved in the formation of meristemoids and shoot meristems with leaf primordia. Thus, secondary tissue differentiation in canna lily cultivar 'Livadia' was formed by histogenesis. Canna meristemoids hydration was up to 90.1-96.4%, including free water fraction - 66.5-83.2%. Among the studied cultivars significant differences were noticed NDASH 'Suevia' cultivar meristemoids contained two times more bound water than 'Livadia' cultivar ones. Analysis of fluorescence induction demonstrated that meristemoid tissues were characterized by low photosynthetic activity (Fm-Fst)/Fm = 0.29-0.35 a.u. Kautsky effect increased slowly (rapid phase is delayed up to 2.5 s), the variable fluorescence (Fv) was 560-700 a.u. However, since the photosynthetic processes in meristemoids were noted, we may suppose that at this stage of the culture processes of vegetative organs formation took place. Photosynthesis activity was higher in 'Suevia' cultivar meristemoids.
Mitrofanova, I.V., Kuzmina, T.N. and Brailko, V.A. 2017. Some histological and physiological features of meristemoids formation in canna lily (Canna × hybrida hort.). Acta Hort. (ISHS) 1167:63-68
canna, meristemoid, cluster, secondary differentiation, hydration, photosynthetic activity, in vitro

Acta Horticulturae