Abstract:
Heen Bovitiya (Osbeckia octandra (L.) DC.), an endemic plant to Sri Lanka, has a great potential for commercial
exploitation as an ornamental flowering herb. O. octandra is propagated mainly through seeds and rarely by
vegetative propagation technique. However, the seeds are very small and characterized by poor germination
rates. Hence, it is vital to develop a mass propagation protocol for the production of the required amount of
planting materials for the commercial level. Therefore, this experiment was carried out to see the effects of
different media on the seed germination percentage at the plant nurseries of Seethawaka botanic garden located
in the wet zone of Sri Lanka from January to March of 2021. Potting media were; sand (T1), sand: soil at 1:1 (T2)
and soil: sand: charcoal 1:1:1 (T3) were tested in a complete randomized design with thirty replicates of each
treatment. Each replicate consisted with a plastic pot (d=10” and h=4”) filled with corresponding germination
media, then sown with 50 seeds per pot then were maintained under 60 % shade net house conditions. Then
seedling emergences were counted on weekly basis to estimate seed germination percentages. The results
indicated that germination percentage was significantly (p<0.05) affected by the media. On the 1st week, the
number of seedlings emerged per pot were lower viz; T1 (9), T2 (14) and in T3 (21) respectively. However,
towards the 4th week, seedling numbers increased and produced 29 (T1), 35 (T2) and 43 (T3) respectively
(P<0.05). On the contrary, germination precentage were calculated in the corresponding weeks, revealed that the
significantly higher germination percentage (85.1±0.4) was showed in T3, while the lowest percentage were
denoted in the T2 (70.0±0.3) and T1(41.9±0.5) suggesting that the potting medium of soil + sand + charcoal in 1:1:1
ratio is recommended as the seed germination medium of O. octandra.
