A study on flowering phenology, synchrony, and pollination mechanism of Dendrobium primulinum Lindl. (Orchidaceae)

Abstract

Studies were conducted on the pollination mechanisms of Dendrobium prim-ulinum, epiphytic orchids distributed from India to South East Asia, Australia and Newzeland. The average longevity of flowers of the species was record-ed 10.1 ± 0.21 days. The species was proved to be strictly self-incompatible and pollinator dependent. Higher flowering synchrony resulted higher repro-ductive output. Out of many insects visitors to the flowers, only two species of bees viz. Andrena cineraria and Bombus species were identified as the successful pollinators for the species. The locations of the insect body where the pollinia attached during the pollination process varied; head in case of Bombus species and thorax in A. cineraria. The reason for the pollen attach-ment at different places of the two pollinators was attributed to the insects’ body size in relation to the size of the floral parts especially the labellum chamber, which was an adaptation character of the orchid species.