摘 要 ：延迟自交被认为是一种生殖适应性，因为它保证了传粉者稀少情况下的种子生产，但当传粉者丰富时，又允许异交占优势。海滨锦葵花在传粉者不足或缺乏时能通过主动的柱头裂片弯曲运动成功实现延迟自花传粉。2002~2005年对江苏盐城滩涂海滨锦葵栽培群体花中发生延迟自花传粉花所占的百分比进行了观测，并于2005年对花内不同停止类型的柱头裂片比进行了调查，结果表明，2002 ~ 2005年间发生延迟自花传粉花所占百分比分别为13.50%±1.62%、14.39%±1.50%、1405%±1.82%和13.47%±1.51%，不同年份间并无显著差异 (F(3, 189) = 6.128, P = 0.085 )。发生延迟自花传粉花所占百分比与气候条件有密切关系，不利天气(多云/雨) (22.11%±0.94%) 明显高于有利天气(晴天) (5.43%±0.43%) (F(1, 189) = 8009.780, P < 0.001)。花内通过花部运动实现自花传粉而停止运动的柱头裂片比在有利天气(晴天)下(18.64%±1.61%)明显低于不利天气(多云/雨天) (70.58%±2.06%) (U = 0.000, W = 465.000, P <0.001)。海滨锦葵这种直接响应于影响传粉者环境之气候条件的延迟自花传粉策略为从个体或花水平上验证繁殖保障假说提供了可能。
Abstract:Delayed selfing is regarded as a reproductive adaptability, because it apparently ensures seed production when pollinators are scarce, yet it allows outcrossing to predominate when they are abundant. Delayed self-pollination by curvature of stigma-lobes occurs in flowers of Kosteletzkya virginica, when pollinators are scarce or absent. Based on the observation data of delayed self-pollination of K.virginica growing in the naturalized population in the Yancheng tideland, Jiangsu province, China and climate data from 2002 to 2005, and the observation data of different stop types of stigma lobes within-flowers in 2005, percentages of flowers undergoing delayed self-pollination and different stop types of stigma lobes were analyzed, and comparing their differences between fine and inclement weather conditions. The conclusions showed that percentages of flowers undergoing delayed self-pollination during 2002-2005 were 13.50%±1.62%、14.39%±1.50%,14.05%±1.82% and 13.47%±1.51%, respectively, and there was not significant difference among different years (F(3, 189) = 6.128, P = 0.085). The percentage of flowers displaying delayed self-pollination to all flowers on cloudy / rain days (22.11%±0.94%) was significant higher than that of sunny days (5.43%±0.43%) (F = 8009.780, P < 0.001). Percentage of stigma lobes of curve stop by floral parts movement on sunny days (18.64%±1.61%) was significant lower than on cloudy / rain days (70.58%±2.06%) (U = 0.000, W = 465.000, P <0.001). Percentage of flowers of K. virginica displaying delayed self-pollination is directly respond to the weather conditions influencing pollinators environments, this provides the potential for testing the reproduction assurance hypothesis in the level of individuals or flowers.