Explant type as a key factor in adventitious organogenesis success of Galanthus nivalis in vitro

Galanthus nivalis (snowdrop) is a popular ornamental, bulbous plant, widely admired for its early spring bloom and delicate white flowers. It also has medicinal significance, with reported health benefits including antioxidant and anti-inflammatory properties. The in vitro propagation of this plant remains challenging, and reports on its micropropagation in the literature are limited.

This study investigated the impact of explant type on biometric parameters during adventitious organogenesis. Two types of explants collected from in vitro cultures of G. nivalis were used: leaf blade fragments (leaf-derived explants) and bulb fragments (bulb-derived explants). Culture was carried out on solidified Murashige and Skoog medium enriched with 30g/L sucrose and the following growth regulators: 5 μM 6-benzyladenine cytokinin (BA) and 0,5 μM auxin 1-naphthaleneacetic acid (NAA). The conditions in the growth chamber, with a 16/8 h photoperiod (day/night), were as follows: temperature 25/23 ± 1°C, 80% relative humidity, PPFD ~ 35 µmol m^-2s^-1. After 6 weeks of culture, biometric observations were carried out. All explants used regenerated (100%), but only leaf-derived explants formed calluses (80%). A higher regeneration of shoots (developing leaves without bulbs at the base) was observed form leaf-derived explants (regeneration rate of 1.00) compared to bulb-derived explants (0.21). Explant type did not significantly affect the regeneration rate of bulbs (closed bulbs without developing leaves). However, the number of bulbs was higher from leaf-derived explants (mean of 7.04 per one explant) compared to bulb-derived explants (2.33). Bulb-derived explants did not regenerate roots, while leaf-derived explants regenerated roots with a rate of 0.94, producing an average of 2.33 new roots with a mean length of 5.8 mm per explant. Explant type did not affect the average number of new shoots (mean of 6.4), nor the average diameter of newly formed bulbs (2.6 mm).

Leaf-derived explants of G. nivalis showed more effective regeneration during in vitro adventitious organogenesis compared to bulb-derived explants, with higher shoot and root formation, as well as a greater number of new bulbs. This potential can be used for improving the propagation efficiency of these plants.