带形蜈蚣藻盘丝体孢子的形成及温度和光照强度对其放散的影响

在实验室条件下, 首次发现了带形蜈蚣藻(Grateloupia turuturu)盘状体产生的丝状体能够形成孢子, 暂命名为“盘丝体孢子”。研究详细观察了该盘丝体孢子的形成过程, 并探讨了不同温度6、12、16、20、24和30℃及不同光照强度10、30、45、60、90和120 μmol/(m2·s)对盘丝体孢子放散的影响。结果表明: (1) 带形蜈蚣藻雌配子体的囊果释放果孢子, 果孢子发育形成盘状体, 盘状体经过诱导再生出单列细胞的丝状体, 丝状体形成多室孢子囊, 并放散出大量盘丝体孢子; (2) 温度和光照强度均对丝状体中盘丝体孢子的放散产生显著影响。在温度为16℃、光照强度为60 μmol/(m2·s)时盘丝体孢子放散量有最大值; (3) 在温度低于12℃或高于24℃时, 盘丝体孢子的放散受到影响, 数量明显减少; (4) 在光照强度低于30 μmol/(m2·s)或高于90 μmol/(m2·s)时, 盘丝体孢子的放散明显受到抑制。研究结果补充了带形蜈蚣藻无性繁殖过程, 为其种质保存、人工育苗及养殖提供更为丰富的理论依据, 为探讨带形蜈蚣藻的起源与演化提供新思路。

EFFECTS OF TEMPERATURE AND LIGHT INTENSITY ON THE FORMATION AND RELEASE OF SPORES OF GRATELOUPIA TURUTURU

We discovered for the first time that Grateloupia turuturu filaments, developed from discoid crusts, had the ability to form spores under laboratory condition,which defined as " disc-filamentospore”. We investigated the formation of disc-filamentospores and the effects of various temperatures (6, 12, 16, 20, 24, 30℃) and light intensities (10, 30, 45, 60, 90, 120 μmol/(m2.s)) on the release of disc-filamentospores. The results indicated that carpospores that formed and released from cystocarps of female gametophyte of G. turuturu, first developed into discoid crusts. The discoid crusts were induced to form filaments of monolayer cells, which formed massive plurilocular sporangiums and released large amounts of disc-filamentospores.Temperature and light intensity significantly affected the releasing efficiency of disc-filamentospores with the maximum level at 16℃ and 60 μmol/(m2·s). The releasing number of disc-filamentospores reduced when the temperature was lower than 12℃ or higher than 24℃. The light intensity with less than 30 μmol/(m2·s) or more than 90 μmol/(m2·s) significantly inhibited the releasing efficiency of disc-filamentospores. Our results improved the asexual reproduction process of Grateloupia turuturu and provided more abundant theoretical basis for its germplasm preservation, artificial breeding and aquaculture. Finally, we suggest a plausible solution to investigate the origin and evolution of Grateloupia turuturu.