不同环境因子对珍稀观赏蕨类金毛狗配子体性别分化的影响

金毛狗Cibotium barometz(L.)J.Sm.]是珍稀观赏蕨类的重要类群,为国家二级重点保护野生植物。该研究以金毛狗孢子为试验材料,探究培养密度、外源赤霉素以及光质等不同环境因子对金毛狗配子体性别分化的影响,为金毛狗人工繁育和蕨类植物配子体性别决定机制研究提供技术支持。结果表明:(1)低配子体培养密度(1个/cm2和5个/cm2)有利于颈卵器和雌配子体形成,随着配子体培养密度增加,颈卵器平均数量及雌配子体比率下降,精子器平均数量以及雄配子体和两性配子体比例增加,但配子体培养密度过高(80个/cm2)会导致大量无性配子体产生。(2)不同配子体培养密度下,随着培养时间延长,两性配子体比率均有增加,且增加幅度基本一致。(3)外源GA4显著抑制颈卵器和雌配子体形成,并显著促进精子器和雄配子体形成;外源GA3对金毛狗配子体性别分化没有显著影响。(4)白光、红光、蓝光等不同光质对金毛狗配子体性别分化未产生显著影响,但会影响配子体的发育和形态建成。

Effect of Different Environmental Factors on the Sex Differentiation of Gametophytes in the Rare Ornamental Fern Cibotium barometz

Cibotium barometz (L.) J. Sm., an important taxa of the rare ornamental ferns, is listed in the Category II of State Key Protected Wild Plants. In present study, spores were used as materials to investigate the effects of different environmental factors (cultivation density, exogenous gibberellin, light quality) on the sex differentiation of C. barometz gametophytes, which could provide technical support for artificial propagation of C. barometz and study on sex determination mechanism of fern gametophytes. The results showed that: (1) The low density of cultivation (1 individual /cm², 5 individuals /cm²) is beneficial for the formation of archegonia and female gametophytes. With cultivation density increasing, number of archegonia per gametophyte and rate of female gametophyte decreased, in the meantime, number of antheridia per gametophyte and rate of male and hermaphroditic gametophyte increased, but excessive cultivation density (80 individuals /cm²) resulted in a mass of asexual gametophytes. (2) With the cultivation time prolonging, the rate of hermaphroditic gametophyte increased in the different cultivation density. (3) Exogenous gibberellin A₄ (GA₄) significantly suppressed the formation of archegonia and female gametophytes, and promoted the formation of antheridia and male gametophytes. However, exogenous gibberellin A₃ (GA₃) had no significant effect on the sex differentiation of C. barometz gametophytes. (4) Light quality (white, red, blue) had no significant effect on the sex differentiation of C. barometz gametophytes, but had some effect on gametophyte development and morphogenesis.