红纤维虾形草(Phyllospadix iwatensis)种子形态及内部特征

The seed morphology and internal characteristics of seagrass, surfgrass Phyllospadix iwatensis

海草床可以为海洋动物提供产卵、索饵、繁育等场所。目前,海草床面积急剧下降,其中我国关于虾形草属(Phyllospadix)海草的研究相对较少,对于虾形草主要繁育载体种子的描述、显微观察和萌发过程方面存在较多空白。本研究以红纤维虾形草(Phyllospadix iwatensis)为研究对象,对其生长环境、种子外部特征、内部结构、萌发过程等进行了定性定量描述。结果表明,虾形草果实种子对于海洋环境有着外部形态与内部结构的适应性,外部形态特点包括独特的果序和果实形状,以及翅状结构和内侧鬃毛,其中果序呈弯虾形,平均长度3.4cm,果实呈马掌形,直径3~4mm,内部结构特征包括胚乳占比大、果皮种皮解剖结构复杂等,具有作为海岸带植被修复工具种的优势。本研究补充了目前对虾形草等海洋沉水植物种子的研究资料,为虾形草海草种质库保护与海草床修复提供了建议和参考。

The global seagrass bed ecosystems are facing multiple threats. For instance, the seagrass Phyllospadix(Zosteraceae) is of great ecological importance and fishery value. And one of the seagrasses surfgrass, Phyllospadix, is relatively poorly studied. In particular, there are more study gaps in the description, micro-observation and germination process of the main breeding carrier, seeds of surfgrass, as well as in the identification of DNA molecules. In this study,Phyllospadix iwatensis was used as the study object to describe its growing environment, external characteristics of seeds,internal structure, germination process, etc. in both qualitative and quantitative ways, and the results show that fruits and seeds of surfgrass have the adaptability on external form and internal structure in the marine environment, and have the advantage of becoming tool species for vegetation restoration in coastal zone. External morphological features include unique fruit inflorescence and fruit shape, as well as wing-like structure and medial mane, of which the fruit inflorescence is curved shrimp-shaped with an average length of 3.4 cm and the fruit is horseshoe-shaped with a diameter of 3-4 mm. The internal structural features include a large proportion of endosperm and complex anatomy of the peel and seed coat. This study complements the lack of in-depth study on the seeds of marine submerged plants, such as surfgrass, and provides valuable suggestions and reference contents for the protection of surfgrass and other types of seagrass seed banks, as well as the restoration of seagrass beds, and also yields a basis for the practical application of surfgrass in seedling restoration.