桑沟湾大叶藻有性繁殖特性的观察研究

Study on sexual reproductive characteristics of eelgrass Zostera marina L. in Sanggou Bay

关键词:  大叶藻  有性繁殖  物候  种子产量  桑沟湾

Key words:  Zostera marina  Sexual reprodctuion  Phenology  Seed production  Sanggou Bay

摘要:

2009年1~8月，对桑沟湾大叶藻有性繁殖特性进行了观测，以期为我国大叶藻的研究及保护工作提供基础资料。4月初，大叶藻花枝明显可见，至5月上旬，柱头直立、花药开裂，花期开始，此时水温为14.8℃。第一个可见果实发现于6月上旬，果实成熟及种子的散落始于7月初，此时水温升至21.4℃。至8月初，水温为21.8℃时，花枝基本不可见，此时种子散落结束。花枝的各分枝向心发育，各分枝上的佛焰苞向顶成熟，花期最初和最后阶段分出的佛焰苞着生较少的子房数，结实率相对较低。花枝密度为114颗/m2，每枝结实67.0个，潜在种子产量为7 638个/m2。

Abstract:

The sexual reproductive traits of eelgrass Zostera marina L. in Sanggou Bay was studied during January to August, 2009. Distinguishable flowering shoots were first observed in early April. Spathes with projecting pistils and dehiscence of anthers were found in mid May, when water temperature was 14.8℃. The first visible fruit was observed in early June. Maturation of fruits and release of seeds started at the beginning of July as water temperature reached 20.4℃. Few flowering shoots were found at the beginning of August and seed release was completed by this time. Branches of reproductive shoots initiated development centripetally while spathes matured acropetally. Spathes produced at the beginning and the end of the flowering phase showed fewer pistils and lower seed setting rate. The average density of flowering shoots was 114 ind/m2 with 67.0 fruits on each shoot. The potential seed production was 7 638 ind/m2.