裙带菜孤雌生殖幼孢子体体细胞诱导2n♀配子体

Induction of diploid female gametophytes from the vegetative cells of parthenogenetic juvenile sporophytes in Undaria pinnatifida

以实验室内保存培养的裙带菜(Undaria pinnatifida)2n♀配子体为实验材料,经切碎培养,促进2n♀配子体成熟,排出卵进行孤雌生殖,形成幼孢子体。将0.5～1.0cm的孤雌生殖幼孢子体的假根切除,从其体细胞中诱导出2n♀配子体。实验结果表明,在10～20℃范围内,培养20d后,在15℃和20℃下的2n♀配子体排出的卵的孤雌生殖率分别为8.4%和7.4%,明显高于10℃下的1%。20℃下诱导培养15d后就出现了2n♀配子体,培养60d后,2n♀配子体的诱导率达到100%;15℃下培养30d后才出现2n♀配子体,60d后的诱导率为38%;而10℃下诱导培养45d后才开始出现2n♀配子体,60d后的诱导率仅为12%。将诱导产生的2n♀配子体切碎,在20℃下培养10d后的成熟率为34%,60d的成熟率达到100%。通过孤雌生殖幼孢子体诱导产生的2n♀配子体与正常♂配子体杂交形成了3n裙带菜幼孢子体。本研究发现了获得大量2n♀配子体的新方法,旨在为裙带菜三倍体幼苗规模化培育奠定基础。

After being excised into several cells of fragments,the indoor incubated 2n female gametophytes of Undaria pinnatifida matured and produced some juvenile sporophytes without fertilization.Then,the 2n female gametophytes were induced from the vegetative cells of the obtained parthenogenetic 2n juvenile sporophytes,which were removed rhizoids and in a 0.5-1.0 cm length.The parthenogenesis rate of the matured 2n female gametophytes reached 8.4% and 7.4% after 20 days of incubation at 20 ℃ and 15 ℃,respectively,which were both higher than 1% at 10 ℃.The 2n female gametophytes were induced after incubation for 15 days at 20 ℃,but for 30 days at 15 ℃ and for 45 days at 10 ℃.The induction rate of the 2n female gametophytes was 100% at 20 ℃,but was 38% at 15 ℃ and 12% at 10 ℃ after 60 days of incubation,respectively.The maturation rate of the induced 2n female gametophytes,after being excised into fragments,reached 34% after incubation for 10 days and 100% for 20 days at 20 ℃,respectively.The 3n juvenile sporophytes were produced by the cross between the induced 2n female gametophyte and the n male gametophyte.In present study a new method of mass production of 2n female gametophytes was founded,which laid a foundation for the scale production of triploid seedlings of Undaria pinnatifida.