Pollination ecology and its implication for conservation of an endangered perennial herb native to the East-Himalaya, Megacodon stylophorus (Gentianaceae)

Background and aims - Megacodon stylophorus (C.B.Clarke) Harry Sm. is an endangered herb native to the East-Himalaya and the Hengduan Mountains, south-west China. We studied reproductive ecology of this species to explore the factors that are critical for its survival and conservation. Methods - We conducted breeding system experiments during 2008 and 2009 in two populations located in the Hengduan Mountains. Key results - The flowers are protandrous and herkogamous, and thus insects are necessary for pollination and seed production. Bumblebees were observed to be the most frequent visitors, and their visitation rates were lower at the higher altitude. Seed production in both populations fluctuated annually, possibly due to pollen limitation, which occurred in both populations in the two years. Conclusions - The pollination level is only marginally responsible for the rarity of this alpine species. We suggest that in situ conservation measures should be given the highest priority at present, considering the strong genetic differentiation among populations.