Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Yunnan, China.
Plant Biol (Stuttg). 2011 Jul;13(4):582-9. doi: 10.1111/j.1438-8677.2010.00423.x. Epub 2010 Dec 22.
According to the concept of pollination syndromes, floral traits reflect specialisation to a particular pollinator or set of pollinators. However, the reproductive biology of endemic, and often specialised, plants may require increased attention as climate change accelerates worldwide. Species of Roscoea endemic to the Himalayan region have striking orchid-like flowers with long corolla tubes, suggesting pollination by long-tongued insects. Until now, the reproductive biology of species of Roscoea has been poorly documented. We investigated the floral biology, breeding system and pollination ecology of R. cautleoides and R. humeana, from Hengduan Mountains, a global biodiversity hotspot in southwest China. We also tested whether floral longevity increases pollination success. Pollination experiments showed that the two species were self-compatible and depended on insects for fruit production. Over several flowering seasons we did not observe any potential pollinators with long tongues that matched the corolla tube visiting flowers in centres of distribution. The principal pollinators observed were pollen-collecting generalist bees, with low visitation frequencies. In general, members of the ginger family are characterised by short-lived (usually 1 day) flowers, but flowers of R. cautleoides and R. humeana last 8 and 6 days, respectively. Removing stigmas decreased fruit set in both study populations. Our results suggest that the original pollinators may have been long-tongued insects that are now absent from the Chinese Himalayas because habitats have responded to climate change. However, long-lived and self-compatible flowers, coupled with the presence of generalist pollinators, are traits that have allowed these gingers to reproduce and continue to persist in the alpine habitats.
根据传粉综合征的概念，花的特征反映了对特定传粉者或一组传粉者的特化。然而，随着全球气候变化的加速，特有植物的生殖生物学，尤其是那些通常具有专门性的植物的生殖生物学，需要引起更多关注。喜马拉雅地区特有的罗氏蕉属植物具有引人注目的兰花状花朵，具有长长的管状花冠，表明它们是由长舌昆虫传粉的。到目前为止，罗氏蕉属植物的生殖生物学记录很少。我们调查了来自中国西南生物多样性热点地区横断山脉的罗氏蕉（R. cautleoides）和罗氏蕉（R. humeana）的花部生物学、繁育系统和传粉生态学。我们还测试了花的寿命是否会增加传粉的成功率。传粉实验表明，这两个物种是自交亲和的，并且依赖昆虫来产生果实。在几个开花季节里，我们没有观察到任何具有与管状花冠相匹配的长舌的潜在传粉者在分布中心访问花朵。观察到的主要传粉者是花粉采集的一般性蜜蜂，访问频率较低。一般来说，姜科植物的特征是花的寿命短（通常为 1 天），但罗氏蕉和罗氏蕉的花分别持续 8 天和 6 天。摘除柱头会降低两个研究种群的果实结实率。我们的研究结果表明，原始的传粉者可能是长舌昆虫，现在已经从中国喜马拉雅山地区消失了，因为栖息地已经对气候变化做出了反应。然而，长寿命和自交亲和的花朵，再加上一般性传粉者的存在，是这些姜科植物能够在高山栖息地繁殖和继续存在的特征。
