Introduction of a seedling production method using vegetative gametophytes to the commercial farming of Laminaria in China

Abstract

Laminaria is the main seaweed species under commercial cultivation in China, which utilizes 80 x 10 9 artificially cultured seedlings each year. This paper reports the large-scale application of seedling production using vegetative gametophytes in Laminaria cultivation. Key techniques, such as the attachment of gametophytes to the collectors and tank culture of seedlings in the hatchery, are examined. The problems of detachment and irregular dispersion of seedlings were also investigated. An efficient and practical seedling production technology was developed, which consists of seeding gametophytes on collectors, control of seawater flow in tanks, washing of collectors and regulation of ambient light, seawater temperature and nutrition supplement. After 2 months of culture, seedlings grown on woven palm rope collectors 0.5 cm in diameter measured up to the national technical standard of China (i.e., > 20 individuals cm −1 at a length of > 1.5 cm, and > 100 individuals cm −1 at a length of 0.2 cm-1.5 cm, desolation rate < 1% and detachment rate < 5%). Compared with spore-derived seedlings, no significant differences in sporophyte recruitment and dispersion pattern were observed. Large-scale production of seedlings for commercial cultivation of 4,000 ha from 2001 to 2006 was conducted successfully.

Zygote-derived seedling production of Sargassum thunbergii: focus on two frequently experienced constraints in tank culture of seaweed

“…However, many of them are impractical due to intensive labor requirements or damage to the host seedlings (Ugarte and Santelices 1992;Pickering et al 1993a, b;Ask and Azanza 2002). However, two methods may be efficient and suitable for S. thunbergii: jet washing during seedling culture, and high-density seeding of host plants (Lignell et al 1987;Lüning and Pang 2003;Xu et al 2009). As an indispensable technique for seedling production of Laminaria japonica, jet washing plays an important role in removing fouling (Xu et al 2009).…”

“…However, two methods may be efficient and suitable for S. thunbergii: jet washing during seedling culture, and high-density seeding of host plants (Lignell et al 1987;Lüning and Pang 2003;Xu et al 2009). As an indispensable technique for seedling production of Laminaria japonica, jet washing plays an important role in removing fouling (Xu et al 2009). Although the method is efficient and easy, it has been rarely adopted in tank culture of macroalgae (Fletcher 1995) probably because of loss of large numbers of host plants.…”

Crossed Effects of Light and Temperature on the Growth and Maturation of Gametophytes in Costaria costata and Undaria pinnatifida

“…· (hybrid) (Pang et al, 1997;Morita et al, 2003;Wu et al, 2004;Choi et al, 2005;Druehl et al, 2005), , , , Westermeier et al, 2006;Hwang et al, 2009;Xu et al, 2009;Hwang et al, 2010). (Wu et al, 1994;Kaas, 1998;Li et al, 1999;Wu et al, 2004;Xu et al, 2009) 20 , (Xu et al, 2009 (Serisawa et al, 2002).…”

Intraspecific crossing of Saccharina japonica using distantly related unialgal gametophytes benefits kelp farming by improving blade quality and productivity at Sanggou Bay, China

“…Though mostly annual in nature, the gametophytes can be grown under strictly controlled conditions for a number of years and be crossed to produce identical sporophytes (Shan and Pang 2009;Xu et al 2009). Such a property has been used to produce the Dongfang 2 and 3 cultivars of S. japonica, in which species from different genera were used (Li et al 2007(Li et al , 2008.…”