SUN-TRACKING FLOWER MOVEMENT AND SEED PRODUCTION OF MOUNTAIN AVENS, DRYAS OCTOPETALA L. IN THE HIGH ARCTIC, NY-ÅLESUND, SVALBARD (19th Symposium on Polar Biology)

• Main Authors: ワダ ナオヤ, Naoya WADA
• Format: Report
• Language: English
• Published: Proceeding 1998
• Subjects: artificial warming; cross pollination; flower heliotropism; High Arctic; seed production; Arctic; Svalbard; Ny-Ålesund; Norway; Dryas octopetala; glacier; Mountain avens; Ny Ålesund; Polar Biology; Proceedings of the NIPR Symposium on Polar Biology
• Online Access: https://nipr.repo.nii.ac.jp/?action=repository_uri&item_id=5371; http://id.nii.ac.jp/1291/00005371/; https://nipr.repo.nii.ac.jp/?action=repository_action_common_download&item_id=5371&item_no=1&attribute_id=18&file_no=1

I observed the sun-tracking behavior, temperature increment within flowers, and seed production of mountain avens, Dry us oclopclala L , occurring near Bragger glacier in Ny-Alesund (78°55'N, 11°56'E), Svalbard in Norway. The flowers showed sun-tracking movement on sunny days, but the movement was mostly found around noon and was not so active throughout a sunny day. The temperature increment of the gynoecmm in flowers facing the sun was ca 2℃ higher than in flowers with their back to the sun Petal removal resulted in considerable reduction of the gynoecmm temperature Insects (mostly mosquitoes) visiting flowers were very infrequent, suggesting that a severe pollinator limitation restricted the crosspollination. During the experiments, flowers of Dryas octopetala did not produce any developed seeds under natural condition (0% seed-set) Cross-pollinated flowers showed 8% seed-set, while flowers which were artificially warmed by small green-houses during the flowering period showed 60% seed-set, indicating that the reproduction of D octopetala is strongly restricted by low temperature during the flowering period, rather than by pollinator limitation, in the population of Ny-Ålesund, Svalbard These results suggest that the sun-tracking behavior and parabola-shaped flower structure with large petals are important for seed-setting success by increasing the gynoecmm temperature.