Qingdao Engineering Research Center for Rural Environment, College of Resources and Environment, Qingdao Agricultural University, Chengyang, Qingdao, Shandong Province 266109, China.
Key Laboratory of Tree Breeding and Cultivation, State Forestry Administration, Research Institute of Forestry, Chinese Academy of Forestry, Beijing 100091, China.
Sci Rep. 2017 Feb 17;7:42784. doi: 10.1038/srep42784.
We studied germination behaviors and persistence mechanism of wild Glehnia littoralis, a typical coastal species at temperate sandy coasts of the North Pacific Ocean, and tested the hypothesis that the coastal plants may have evolved special seeds adapting to the coasts, by which they recruit and persist easily, occupying the coasts as ideal habitats. In the Shandong Peninsula, China, we investigated temperature and moisture conditions of coast sand in relation to germination and evaluated effects of sand burial, seawater immersion and sowing time on germination. When germination began, daily dawn temperatures of sand were about 10 °C and daily noon temperatures were about 25 °C; the temperatures were not different in the sand <8 cm deep. The sand at these depths showed a significant difference in moisture contents. The seeds exhibited large germination rates if sand burial was at depths >= 3 cm and winter freezing was kept longer than 2.5 months. Seeds experiencing seawater immersion were able to germinate well. These evidences suggest that G. littoralis has evolved special seeds adapting to seawater dispersal and specific season rhythm. By the seeds, G. littoralis occupies temperate sandy coasts as ideal habitats to persist.
我们研究了北太平洋温带沙质海岸典型沿海物种——辽沙参的萌发行为和持久机制，并通过实验检验了一个假设，即沿海植物可能已经进化出适应沿海环境的特殊种子，使它们能够更容易地繁殖和生存，占据沿海地区作为理想的栖息地。在中国山东半岛，我们调查了与萌发有关的海岸砂的温度和湿度条件，并评估了砂埋、海水浸泡和播种时间对萌发的影响。当萌发开始时，砂的每日黎明温度约为 10°C，每日中午温度约为 25°C；8cm 深以下的砂温没有差异。这些深度的砂在含水量上存在显著差异。如果砂埋深度>=3cm，并且冬季冻结时间超过 2.5 个月，种子的萌发率就会很高。经历海水浸泡的种子能够很好地萌发。这些证据表明，辽沙参已经进化出适应海水传播和特定季节节律的特殊种子。通过这些种子，辽沙参占据了温带沙质海岸作为理想的栖息地得以持久存在。
