Morphological comparison of floral nectaries in Musaceae, with reference to its pollinators
芭蕉科花蜜腺形态比较: 兼论其与传粉者的关系

The floral nectaries of three species of Musaceae s. s. representing the genera Musa, Ensete and Musella were comparatively investigated. Our observations revealed that nectaries of these three genera belonged to the interlocular septal type. In female flowers, nectaries were limited to the upper part of the ovaries above the locules, while in male flowers (with aborted ovaries) nectaries entirely occupied the aborted ovaries. A transection of nectary ducts suggested a complex and highly proliferated labyrinthine structure. The three species shared a few common features in the palisade-like epithelial cells, vascular supplies, and nectary openings. However, they showed some differences in longitudinal section and transectinal outline. The nectaries of Ensete glaucum had the highest starch content, and those of Musa basjoo and E. glaucum had fibrillar material presented in nectar ducts. Pollination syndromes among the three species showed high diversity, while inflorescence and flower characters (such as pendant or erect inflorescences, bract color, nectar volume and production over time, etc.) and pollination patterns were highly correlated. There were no strong correlations between nectary structures and pollinator behavior, although gelatinous or watery nectar was associated with the foraging preference of pollinators.