Chin J Plant Ecol ›› 2009, Vol. 33 ›› Issue (1): 89-96.DOI: 10.3773/j.issn.1005-264x.2009.01.010

• Research Articles • Previous Articles     Next Articles

EFFECTS OF FLORAL LONGEVITY ON MALE AND FEMALE FITNESS IN HEDYCHIUM VILLOSUM VAR. VILLOSUM

GAO Jiang-Yun(), YANG Zi-Hui, LI Qing-Jun   

  1. Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla, Yunnan 666303, China
  • Received:2008-06-06 Accepted:2008-09-10 Online:2008-06-06 Published:2009-01-30

Abstract:

Aims Floral longevity is assumed to reflect a balance between the benefit of increased pollination success and the cost of flower maintenance. Hedychium is the only large genus distributed from the tropics to high elevations in the Zingiberaceae. Members of this genus vary greatly in floral longevity. The floral longevity of H. villosum var. villosum is 5 days, which is much longer than other sympatric gingers. Our objective was to assess the effects of floral longevity on male and female fitness of H. villosum var. villosum through manipulated experiments.
Methods We reduced the functional floral longevity for female function by clipping stigmas and measured the fruit-set of different treatments to test whether long flowering duration increased female fitness. We compared the pollen grain number of flowers in different stages to determine if long floral longevity benefited pollen dispersal.
Important findings Fruit-set increased with increased female functional duration. Flowers with functional floral longevity of 1 day had only 1.85% ± 1.59% fruit-set, which was significantly lower than 20.96% ± 4.13% fruit-set of control flowers with natural longevity. Mean pollen grain number was similar in unopened flowers and flowers 1 day after anthesis, but less in flowers 2, 3 and 4 days after anthesis. These results indicate that long floral longevity is advantageous to both female and male fitness in H. villosum var. villosum. Long floral longevity may contribute to exploring new habitats and spreading toward high elevation areas from tropical areas in the Zingiberaceae.

Key words: floral longevity, male fitness, female fitness, Hedychium villosum var. villosum, Zingiberaceae