Studies on the association of wild orchid (Dendrobium spp) with different types of agro-forestry tree species

Wild orchid (Dendrobium spp.) is naturally available orchid, which specially associated with the specific tree species. It gives scenic beauty to the environment and protects the bio diversity as well. Survival ability and growth performances of wild orchid vary according to the tree species. Wild orchid is highly adaptable to the Mee (Madhuca longifolia) and sapota (Manilkara zapota (L). Limiting of these plants, natural survival of wild orchid is questionable. Therefore it is important to select proper agro-forestry tree species for the survival and higher growth ability of wild orchid.
For this purpose, an experiment was carried out at the Faculty of Agriculture, University of Ruhuna, Mapalana, Kamburupitiya during May – September, 2008. Different agro-forestry tree species such as Jak (Artocarpus heterophyllus), Rubber (Hevea brassilensis), Acasia (Acasia mangium), Sapathilla (Manilkara zapota (L), Mee (Madhuca longifolia), Ahela (Cassia fistula Linn) and Kiripalu (Isonandra compta) were used and five plants from each species were used for the experiment. Five wild orchid plants with similar growth stage per tree were used and coir fibre with twine used to attach the wild orchid plant to the tree species. Data on survival percentage, number of leaves, deformed or dead leaves, number of pods and flower buds were taken as different parameters. Data were analyzed using Analysis of Variance (ANOVA) with Statistical Analysis System (SAS).
Results revealed that, higher survival percentage (100%) was recorded in wild orchid associated with Hevea brassilensis, Acasia mangium as well as Madhuca longifolia and lower survival percentage (33.3 %) was recorded in wild orchid associate with Isonandra compta trees. Higher number of leaves, deformed and dead leaves, number of pods and flower buds were recorded in with orchid associate with Acasia mangium.
Acasia mangium is the most promising tree species which associate with the wild orchid in the sense of survival as well as growth parameters.

Key words: Agro-forestry tree, Association, Acasia, Survival ability, Wild orchid

I.R. Palihakkara and N.D.N. Priyadarshani
Department of Crop Science, Faculty of Agriculture, University of Ruhana, Mapalana, Kamburupitiya