节能型海带育苗新技术——黑暗流水储存配子体

Preserving gametophytes on substrates as an economical approach for the production of Saccharina japonica seedlings

目前采用的海带苗培育方法已经有50多年的历史,它将21～28℃的自然海水降温至6～8℃用于育苗。缺点是海水降温成本高、管理需要人工多。而本技术在育苗过程中的一定时期,将苗帘集中堆放,在流水黑暗条件下储存配子体14 d,储存期间无需人工管理。以此配子体储存技术,可以将海带育苗平均水温从目前的7℃左右提高到10℃左右。

The conventional production of Saccharina japonica seedlings requires the malntenance of cool-water cultivation at 6～8℃ for about 70 days from early August to mid October due to stringent temperature requirements of the sporophytes that the sporangial sori on parental plants are unable to tolerate temperature above 21℃, and sporelings are unable to tolerate above 19℃. It is known that the optimal temperatures for gametophyte and sporeling growth are approximately 15℃ and 10℃, respectively, under which seedlings reach a transplantable size by late September, requiring only 45 days of growth. Because current sea temperatures often exceed 25℃, which is unfavourable to seedling development, seedlings must be cultivated in hatcheries for additional 25 days to meet the requirement for the subsequent growth of sporelings in the sea. The present findings demonstrate that the entire cultivation process can be conducted at temperature（10±0.5）℃ when gametophytes are malntalned in dark on sub-strate panels （1.2×0.5 m, made of palm rope with 1 cm in diametre） in running water at （10±0.5）℃. This technol-ogy for the production of S. japonica seedlings can reduce the energy consumption associated with water cooling by ralsing cultivation temperature from 6～8℃ to 10℃, and minimize the labour input required for malntenance ac-tivities, such as regulating light levels and cleaning the substrate panels.