用裙带菜孤雌生殖的幼孢子体体细胞诱导雌配子体的研究

Induction of female gametophytes by vegetative parthenogenetic cells of juvenile sporophytes in seaweed Undaria pinnatifida

在裙带菜雌配子体的切碎培养中，通过成熟的卵孤雌生殖获得幼孢子体，经染色体观察其染色体数为30条，而正常幼孢子体的染色体为60条。采用切除假根的方法从孤雌生殖幼孢子体体细胞中诱导出雌配子体。在设定的不同温度下，20℃下诱导5d时开始出现雌配子体，培养60d后雌配子体的诱导率达到100％；15℃下诱导5d后出现雌配子体，培养60d后的诱导率为45％；10℃下诱导45d后才开始出现雌配子体，培养60d后的诱导率仅为12％。将诱导产生的雌配子体切碎，在20℃下培养5d后开始成熟，10d后成熟率为75％，15d后成熟率达到100％，与对照组正常的雌配子体无明显差异（P〉0．05）。使用孤雌生殖幼孢子体诱导产生的雌配子体与正常雄配子体杂交，幼孢子体的形成率为88％，与正常雌雄配子体杂交的幼孢子体的形成率（92％）差异不显著（P〉0．05）。将诱导产生的雌配子体与正常雄配子体混合切碎并撒在维尼纶育苗绳上，30d后培育出藻体长度为1—2mm的裙带菜幼苗。

Thirty chromosomes were observed in rophytes of mature seaweed Undaria pinnatifida the parthenogenetic cells of fragments excised in the juvenile spowhile sixty chromosomes were found in the normal juvenile sporo- phytes. Then the female gametophytes were induced from the vegetative cells of the parthenogenesis juvenile sporophytes whose rhizoids were cut off. Nearly 100% of female gametophytes were induced at 20℃, higher than 45% at 15 ℃ and 12% at 10 ℃. The induced female gametophytes had 100% of maturation rate by being excised into fragments at 20 ℃ 15 days after culture, without significant difference between the induced female gametophytes and the normal ones （ P 〉 0.05 ）. There was also no significant difference in the production rate of young sporo- phytes between the group of crossing induced female gametophytes and normal male ones（ 88% ） and the group of crossing normal female with normal male（92% ） （P 〉 0.05 ）. The mixture of induced female gametophytes and normal male ones were excised into fragments and then spread on vinylon strings. The seedlings with length of 1 -2 mm were appearance 30 days after culture.