观赏蕨类姬蕨同配子体自交的孢子体萌发和发育特性

Characteristics of Intragametophytic Selfing of Ornamental Ferns Hypolepis punctata on Sporophyte Germination and Development

[目的]评估交配形式对蕨类繁殖的影响。[方法]以姬蕨(Hypolepis punctata)为例,设计配子体单独培养(同配自交)和混合培养(混交)比较试验,比较两种交配系统下孢子体萌发状态(萌发率、存活率),孢子体成长情况及生长速率。[结果]尽管自交幼苗生长趋势弱于混交个体,单独培养产生的完全纯合的姬蕨孢子体最终存活率达到62.5%,说明蕨类的自交确实可以导致近交衰退,但仍然具有可接受的存活能力,单个孢子仍有很大概率上延续种群。蕨类植物由于其特殊的生活史特性,可通过单独培养得到完全纯合的自交个体,从而得到性状稳定的品系。[结论]该研究中单独培养技术在园艺育种方向具有很好的应用前景。

[Objective]The aim was to evaluate the influence of mating pattern on fern reproduction.[Method]Taking Hypolepis punctata as a case,a comparative experiment of separately and mixed culturing of gametophytes was designed to compare the germination rate,survival rate,sporophyte growth and growth rate of sporophyte under two mating systems.[Result]The final survival rate of the completely homozygous sporophyte produced by separately culturing reached 62.5%,although their growth performance was weaker than that of mixed-crossing individuals.It suggests that selfing ferns can indeed lead to inbreeding depression,but still have a high ability to survive,which make a single spore has a high probability of continuing the population.Due to the special life-history characteristics of fern,we can obtain completely homozygous selfing individuals as trait-stable strains through separately culturing.[Conclusion]This study proved that the separately culturing technique is applicable in horticultural breeding.