海洋深層水で培養した植物着生性無節サンゴモ，モカサ属1種の成長(Growth of an Epiphytic Crustose Coralline Alga (Pneophyllum sp.) Cultured in Deep Seawater)
- 標題
- 海洋深層水で培養した植物着生性無節サンゴモ，モカサ属1種の成長(Growth of an Epiphytic Crustose Coralline Alga (Pneophyllum sp.) Cultured in Deep Seawater)
- 作者
- 藤田大介・渡辺梨里・Rhea Joy Carton(Daisuke Fujita, Riri Watanabe and Rhea Joy Carton)
- 文件屬性
- 日本研究
- 知識分類
- 水產養殖
- 出版年
- 2014
- 刊名
- 海洋深層水研究
- 卷
- 14
- 期
- 3
- 頁
- P177-184
- 點閱數
- 2392
摘要
モカサ属の小型種は，採集や培養，観察が容易，胞子着生が迅速かっ短命で，無節サンゴモの モデルや教材生物となりうる． 本研究では館山産モカサ属1 種の胞子をGrund 改変培地（リン濃 度1/4, MGM*1/4P)，表層海水（SSW, pH 8.3)，汲み置き富山湾深層水（DSW, pH 7.9）およ びNaOHでpH調節した深層水（ADSW, pH 8.3）で培養した． MGM*1/4Pでは80 umol・m-2・s-i で5 -25Cの5条件，その20セで40 ・100 .imol・m-2・s-i を加え，他の培養液では15でと20セ，80 imol m-2・s-iとした． 加日後の藻体は概して高水温，高光強度で大きかった． MGM*1/4Pでは2 カ月以内に枯死したが，他の培養液では成熟し，DSW とSSW 15セでは7カ月間生育した． 以上， 汲み置き深層水はやや酸性であるが本種の培養が可能であることを確かめた．
Among crustose coralline algae, epiphytic small and thin species of Pneophyllum can be a 'model' or an 'experimental alga', because of its almost year-round maturation, quick attachment of spores, ephemeral nature and ease in collection, laboratory culture and microscopic observation. In the present study, an epiphytic species of Pneophyllum was collected together with its host seagrass Zostera marina at Okinoshima, Tateyama, Chiba Prefecture and released spores were cultured in various media to find the optimum culture condition. The released spores (mixtures of carpo-spores and tetraspores) were cultured in deep seawater (DSW, pumped from a depth of 384 m in Toyama Bay and stocked in the refrigerator, pH 7.9), DSW alkalized with NaOH (ADSW, pH 83), surface seawater (SSW, pH 83) and modified Grund medium (MGM) containing a quarter concentration of phosphate (MGM*1/4P, pH 83). Water temperature was kept at 15 and 200C under long day irradiance of 80 jimol・m-2・5-1,L:D=14:10). Only in MGM-1/4P, in which the life cycle of Pneophyllum zostericolum had been completed in our previous study, three water temperatures 5, 10 and 250C（at the above irradiance) and two light intensities 40 and 100 umol・m-2・s-' (at a temperature of 20C)were added to the culture series. After 20 d, it was found that thallus was larger at higher temperatures and higher light intensities but no significant differences were found except a low value in DSW at 150C. In MGM*1/4P, all thalli died within 2 months without reaching maturation. In SSW, DSW and ADSW, thalli matured, among which those cultured in DSW (15 and 200C) and SSW(150C)survived for seven months. Therefore, pumped and stocked DSW can be a culture media for the species in spite of slightly low pH.
Among crustose coralline algae, epiphytic small and thin species of Pneophyllum can be a 'model' or an 'experimental alga', because of its almost year-round maturation, quick attachment of spores, ephemeral nature and ease in collection, laboratory culture and microscopic observation. In the present study, an epiphytic species of Pneophyllum was collected together with its host seagrass Zostera marina at Okinoshima, Tateyama, Chiba Prefecture and released spores were cultured in various media to find the optimum culture condition. The released spores (mixtures of carpo-spores and tetraspores) were cultured in deep seawater (DSW, pumped from a depth of 384 m in Toyama Bay and stocked in the refrigerator, pH 7.9), DSW alkalized with NaOH (ADSW, pH 83), surface seawater (SSW, pH 83) and modified Grund medium (MGM) containing a quarter concentration of phosphate (MGM*1/4P, pH 83). Water temperature was kept at 15 and 200C under long day irradiance of 80 jimol・m-2・5-1,L:D=14:10). Only in MGM-1/4P, in which the life cycle of Pneophyllum zostericolum had been completed in our previous study, three water temperatures 5, 10 and 250C（at the above irradiance) and two light intensities 40 and 100 umol・m-2・s-' (at a temperature of 20C)were added to the culture series. After 20 d, it was found that thallus was larger at higher temperatures and higher light intensities but no significant differences were found except a low value in DSW at 150C. In MGM*1/4P, all thalli died within 2 months without reaching maturation. In SSW, DSW and ADSW, thalli matured, among which those cultured in DSW (15 and 200C) and SSW(150C)survived for seven months. Therefore, pumped and stocked DSW can be a culture media for the species in spite of slightly low pH.