Onset and establishment of symbioses in early life stage of hermatypic corals

造礁珊瑚中存在单细胞的共生甲藻，但对于珊瑚早期共生的时间和详细过程知之甚少。我研究了在实验室和现场条件下，通过珊瑚的早期幼虫阶段的共生关系的发病。结果表明：（1）在实验室条件下，9种珊瑚的幼虫均获得了共生体。（2）现场培养的仔鱼获得了不同基因型的共生体;（3）1月龄和1岁以上的水螅体内均发现了多种类型的共生体，但藻型不同。珊瑚在早期阶段会获得任何基因型的共生体，并可能在长大后选择合适的共生体作为长期伴侣。

Reef-building corals harbor unicellular symbiotic dinoflagellates, but little is known regarding the timing and detailed process of the onset of symbiosis in early stage of corals. I examined the onset of symbiosis through the early larval stage of corals under both laboratory and field conditions. The results are as follows : (1)The larvae from 9 corals acquired symbionts under the laboratory conditions. The larval development of both a mouth and coelenteron play important roles in symbiont acquisition, (2)The larvae cultured in site acquired different genotypes of symbionts, (3)Several types of symbionts were found in both one-month-old and more than one-year-old polyps, however, algal types differed. Corals in early stages acquire any genotypes of symbionts and may select suitable ones as longer-term partners when they grow up.