Gametophyte adherence

<b>How sticky is sticky? A note on gametophyte adherence of the macroalga </b><b><i>Saccharina latissima</i></b><b> (Phaeophyceae)</b>Eoghan Mánus Cunningham^1,2*, Pamela J. Walsh^1,2, Louise Kregting³Temperate marine systems are ideal environments for expanding global seaweed aquaculture, yet high costs, particularly from macroalgal nursery facilities, have become a limiting factor for industry development. Recent research has explored the use of binder-seeding, whereby juvenile kelp life stages are seeded directly onto rope using adhesive solutions and deployed directly at sea. This method is used to reduce our reliance on nursery facilities and reduce aquaculture costs. While binder-seeding has shown mixed results, a more simplistic approach by Klaus Lüning has received less attention. Klaus Lüning (1979) commented that kelp gametophytes were naturally ‘sticky’ and attach to substrata within ‘a short time’, potentially highlighting a natural and more cost-effective seeding technique. Here, we explored the natural adherence of <i>Saccharina latissima </i>gametophytes to aquaculture twine. Cultures were sprayed onto twine and left to adhere for eight increasing time periods, before being submerged in seawater and measured after 10 weeks of growth. Gametophytes were found to adhere and grow successfully on twine after immediate submergence in seawater, however significant differences in sporophyte lengths and density after 10 weeks growth were observed among time treatments. Sporophyte lengths and densities were found to be highest when the culture was left to adhere for 30 minutes prior to submergence in seawater, potentially highlighting a time-sensitive sweet spot for natural gametophyte seeding. Further, we confirm that Lüning’s observation of kelp gametophytes sticking to substrata after a ‘short time’ was in fact ‘immediate’, thereby shorter than previously thought.

《何谓“粘性”？关于大型藻类（macroalga）糖海带（*Saccharina latissima*，褐藻门Phaeophyceae）配子体（gametophyte）粘附性的研究简报》
埃汉·马努斯·坎宁安^1,2*，帕梅拉·J·沃尔什^1,2，路易丝·克雷廷³
温带海洋系统是拓展全球海藻养殖业的理想环境，但高昂的成本——尤其是大型藻类育苗设施带来的成本——已成为制约产业发展的瓶颈。近期已有研究探索了粘合剂播种法（binder-seeding）的应用路径：即利用粘合剂溶液将幼龄海带生活史阶段的个体直接播种于绳缆上，并直接投放到海域中。该方法旨在降低对育苗设施的依赖，进而缩减水产养殖成本。尽管粘合剂播种法的应用效果褒贬不一，但克劳斯·吕宁提出的更为简便的方法却鲜受关注。克劳斯·吕宁于1979年指出，海带配子体天生具有“粘性”，可在“较短时间内”附着于基质（substrata）表面，这一发现或可催生一种天然且成本更低廉的播种技术。本研究针对糖海带配子体在养殖绳缆（aquaculture twine）上的自然粘附特性展开探究：将配子体培养液喷洒至绳缆上，设置8组递增的粘附时长梯度，随后将绳缆浸没于海水中，待生长10周后进行相关指标测定。研究发现，即便即刻将绳缆浸没于海水中，配子体仍可在绳缆上成功附着并生长，但不同粘附时长处理组的孢子体（sporophyte）长度与密度在生长10周后呈现出显著差异。结果显示，当培养液在浸没前的粘附时长为30分钟时，孢子体的长度与密度均达到峰值，这表明天然配子体播种存在一个对时长敏感的最优窗口期。此外，本研究证实，吕宁所提及的海带配子体可在“较短时间内”附着于基质的结论，实际应为“即刻附着”，即其附着时长比此前认知的更短。