Insect pollination of Musella (Musaceae), a monotypic genus endemic to Yunnan, China

 The pollination biology of Musella lasiocarpa (Franch.) C. Y. Wu ex H. W. Li, a monotypic genus in the banana family (Musaceae) endemic to southwestern China, was investigated. Floral phenology, nectar production, and flower visitors were observed, measured, and recorded. Bagging experiments and comparative breeding system studies were carried out at different study sites and in different seasons. Our results revealed four important aspects of the reproductive biology of Musella. 1) This species blooms year round, but most flowering is concentrated from February to August. The longevity of female flowers is greater than that of male flowers and opening of both types of flowers occurs at anytime during the day, but is concentrated in the morning. 2) Although nectar is produced uniformly while flowers are open, the nectar volume and rate of female flowers are significantly higher than that of male flowers. 3) Insects, such as bumblebees (Bombus eximius and B. montivolans), honeybees (Apis cerana and A. florea), and wasps (Vespa mandarinia) are the primary floral visitors and show a preference for female flowers. 4) Both fruit and seed set are pollinator-limited at both study sites. A comparison of the floral biology and pollination characteristics among the three genera in the banana family suggests that insect pollination has played an important role in the reproductive isolation and breeding system evolution of Musella. Received February 14, 2002; accepted March 26, 2002 Published online: November 22, 2002 Addresses of authors: Aizhong Liu, W. John Kress (correspondence, e-mail: kress.john@nmnh.si.edu), Botany, MRC-166, United States National Herbarium, National Museum of Natural History, Smithsonian Institution, PO Box 37012, Washington DC 20013-7012, USA. Hong Wang, De-Zhu Li (dzl@public.km.yn.cn), Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650204, China.