Pollination Ecology and Breeding System of Impatiens trichocarpa Hook, f. (Balsaminaceae): An Endemic Balsam of Western Ghats

摘要

A study of floral phenology, pollen production, foraging nature of flower visitors and breeding systems were studied in Impatiens trichocarpa Hook. f. an endemic balsam of Western Ghats. The flowers are beautifully coloured and open in the night and continue up to morning. Anther dehisced one day before anthesis which confirmed the protandrous condition of the flower. Stigmas are receptive at the time of anthesis and remains so far 20 hour. Flowers offer pollen and nectar to the visitors. Honey bees, hawk moths, butterflies, flies etc. are the major pollinators of Impatiens trichocarpa. Manual pollinations revealed that the species permits geitonogamous and xenogamous type of pollinations. The percentage of fruit set in manually pollinated flowers is higher than that resulting from open pollination. Its high altitude habitat, narrow environmental niche, fragmentation of populations, low percentage of seed germination and floral damage caused by the insect could be the reasons for its limited distribution in the wild.