Pollination in an endemic and threatened monoecious herb Begonia satrapis C.B. Clarke (Begoniaceae) in the eastern Himalaya, India

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Subhankar Gurung
Aditya Pradhan
Arun Chettri

Abstract

Begonia satrapis was studied for its pollination aspects at Sumbuk, Sikkim, India.  The floral details and the foraging behaviour of insects visiting the flowers were examined to define the pollination syndrome and its functionality for the success of sexual reproduction in this species.  The flowers do not produce nectar and offer only pollen as floral reward to foraging insects.  Therefore, male flowers were foraged more for its pollen than the female flowers.  There was a significant difference in the visit to male and female flowers by both Apis florea and Bombus breviceps, respectively.  The bees spent more time on male flowers than on female flowers.  The bees appear to rely on visual stimuli to visit male and female flowers.  The plant produces abundant fruit and seed set in both hand and open-pollinations indicating that it is facultatively xenogamous. The female flowers lacking any reward resemble male flowers and in effect are pollinated by deceit.


 

Article Details

Section
Communications
Author Biographies

Subhankar Gurung, Taxonomy & Biodiversity Lab, Department of Botany, Sikkim University, 6th Mile, Tadong, Gangtok, Sikkim 737102, India.

Subhankar Gurung is currently pursuing his PhD in Department of Botany, Sikkim University, India. His interest lies in studying the reproductive biology of the plant with special emphasis on understanding the role of pollinators.

Aditya Pradhan, Taxonomy & Biodiversity Lab, Department of Botany, Sikkim University, 6th Mile, Tadong, Gangtok, Sikkim 737102, India.

Aditya Pradhan is a PhD scholar in Department of Botany, Sikkim University. He is currently working as a Junior Project Fellow (JPF) and is studying the diversity and distribution of Genus Begonia in Sikkim Himalaya.

Arun Chettri, Taxonomy & Biodiversity Lab, Department of Botany, Sikkim University, 6th Mile, Tadong, Gangtok, Sikkim 737102, India.

Dr. Arun Chettri is a faculty in the Department of Botany, Sikkim University. He is a plant taxonomists/ecologist who has worked extensively on plant diversity, taxonomy, ecology and conservation of threatened plants in different forests types in North East India in particular in Sikkim.

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