Laboratory seed germination of Hydrangea L. species depending on germination methods and genotype
Uman National University, Faculty of Forestry and Landscape Gardening, Instytutska Str., UA20305 Uman, Ukraine
*Correspondence: abrovdi@ukr.net
Abstract:
The aim of the study was to determine the effect of germination methods and cultivar characteristics of plants of the genus Hydrangea L. on laboratory seed germination and to identify approaches for optimising germination protocols to obtain high-quality seeds. It was found that, on average across Hydrangea species, the highest seed germination (80%) was achieved on moistened filter paper, whereas the lowest germination (52%) was recorded using a paper substrate (two layers below and one above the seeds). Among all species, Hydrangea paniculata exhibited the lowest germination, ranging from 46% to 67% across the germination methods evaluated. The highest germination (87%) was recorded for Hydrangea macrophylla on moistened filter paper. Analysis of variance (ANOVA) showed that the factor ‘hydrangea species’ had the greatest effect on seed germination, accounting for 98.08% of the total variation. In both cultivars of Hydrangea paniculata, seed germination was significantly lower throughout the study than in the cultivars of Hydrangea macrophylla and Hydrangea arborescens, ranging from 64% to 68%. The results further showed that hydrangea seeds responded only slightly to pre-germination cooling. On average across species, the mean germination of non-cooled seeds was 80%. Cooling for 5 days reduced germination, whereas cooling for 10 and 20 days increased germination by only 1% relative to the non-cooled control. Irrespective of the treatment applied, the highest and nearly identical germination was observed in Hydrangea macrophylla and Hydrangea arborescens, whereas Hydrangea paniculata showed significantly lower germination.
Key words:
germination, influencing factor, seed quality, temperature, variety