【摘要】 于2006年3-5月在大连沿海萱藻[Scytosiphon lomentaria(Lyngbye)Link]的繁殖期内,采集具有多室配子囊的成熟萱藻,采用阴干刺激方法获得配子并在室内培育形成盘状体。观察结果显示,在20℃和15℃下,盘状体表面细胞生长出丝状体和叶状体。叶状体经生长后沿藻体纵轴裂开又形成了丝状体。丝状体上与基质接触的细胞进行放射状分裂形成盘状体,未与基质接触的细胞在继续分裂增加藻体长度的同时,在丝状体上形成了许多节状细胞团,节状细胞团与基质接触后向周边分裂又形成了盘状体。由丝状体形成的盘状体在15℃和10℃下培养2个月后形成了单室孢子囊。单室孢子囊成熟后经阴干刺激可放出游孢子,游孢子附着后萌发为直立管状萱藻幼苗。实验结果表明,在萱藻生活史中的盘状体阶段还存在盘状体→丝状体→盘状体与盘状体→叶状体→丝状体→盘状体2个循环。盘状体阶段这2个循环的存在,改变了从配子或合子获得盘状体的单一途径。利用丝状体游离培养生长速度快以及节状细胞团切碎后能在短时间内形成盘状体的特性,在室内进行人工增殖丝状体,当节状细胞团出现后将丝状体切碎,可以获得大量盘状体,通过室内培养使盘状体形成孢子囊并放出孢子,经孢子采苗后在室内培育出萱藻幼苗。本研究旨在为萱藻人工育苗探索一条新路。更多还原

【Abstract】 Scytosiphon lomentaria used in the present study were collected in the coast of Dalian from March to May in 2006. After being dried in shade,the mature thalli bearing plurilocular gametangia were immersed into sterile seawater to discharge the gametes. The released gametes were settled and developed into crusts. Filaments and blades were germinated from the surface of crusts by cell division at 20 ℃ and 15 ℃ . The cultured blade were developed into filaments by dehiscing in its apical axis. The bottom cells of the prostrate filaments gave rise to crusts strongly adherent to the substratum. The other cells continued to develop and became knotted by transverse and longitudinal divisions. The knotted structures that had prostrate growth also formed crusts. The crusts derived from the filaments produced unilocular sporangia at 15 ℃ and 10 ℃ . The mature unilocular sporangia released zoospores after being semi-dried. The zoospores developed into erect tubular germlings in cultures. The results showed that there existed another two cycles in crustose stage of Scytosiphon lomentaria. One cycle was from crusts to filaments to crusts. The other one was from crusts to blades to filaments to crusts. The two cycles gave two new ways in producing crusts,which only gained by the generating of gametes or zygotes formerly. For the filaments were easily and quickly propagated and the crusts were fleetly formed by the knocked structures,the filaments were excised into fragments to produce crusts,which could produce unilocular sporangia. After the released zoospores were seeded on the vinylon ropes,seedlings were gained by indoor culture. This was the new way for the artificial seeding of Scytosiphon lomentaria.更多还原