Pollination of Symplocarpus renifolius Schott ex Miquel (Araceae) in Korea

Abstract

The pollination system of Symplocarpus renifolius Schott ex Miquel was investigated in the natural population of Korea. The various arthropods of 15 species, 10 families, 5 orders, 2 classes (mainly Diptera) visited on the flowers of S. renifolius, and captured during the visitation. The dipterous insects were considered as the most effective pollen vector but there were no legitimate pollinators which have associated specially with S. renifolius. All visitors having feeding activity on the flower fed on pollens of S. renifolius. The visitation frequency had a peak at 3-4 PM and no visitor was recognized in night time. The flowers of S. renifolius last over a week and they are protogynous. It is also confirmed that the flower of S. renifolius is self-incompatible and cross-pollination by vectors is critical for successful seed setting. In the estimation of thermometric changes in air (Ta) and spathe (Ts), the changing range of Ts was less than that of Ta by 3.6℃, which suggest that spathe provide more stable thermal environment to arthropods. In the observation of the floral structures, the possibility to lower autogamy were recognized in the shapes of anther, perianth and spadix of S. renifolius. The trapping effect of wandering arthropods was suggested as another role of spathe. The floral parts in most investigated individuals of S. renifolius were damaged by Jay (Garruius glandarinus). The conservation strategies (in situ) based on the reproductive vulnerabilities of S. renifolius, which were induced from random visitation of arthropods and destruction of floral parts by wild animals were briefly proposed.