Reproductive Biology of Gametophytes of Cyathea podophylla (Hook.) Copel.

鬼桫欏配子體的繁殖生物學

邱文良(Wen-Liang Chiou) ； 李沛軒(Pei-Hsuan Lee) ； 應紹舜(Shao-Shun Ying)

《台灣林業科學》 15卷1期 (2000/03) Pp. 1-12

https://doi.org/10.7075/TJFS.200003.0001

摘要

本文著重於與鬼桫欏配子體繁殖有關之各種特性的研究，如生長習性，配子器發生順序，促精素，倍體性，及遺傳負荷等。鬼桫欏之幼配子體並未受到蕨、海金沙、水蕨及其本種之成熟配子體影響而促進其藏精器的產生，其孢子亦未在所有處理之黑暗環境中發芽，此結果顯示本種不產生促精素（或亦無發芽促進素）。此外，由雄性至兩性的性表現次序，亦顯示不符合促精素的作用模式。孢子母細胞之染色體數為69(下標 Ⅱ)，顯示本種孢子體為二倍體，高遺傳負荷顯示鬼桫欏之繁殖主要藉由異配子交配，特別是異配子體雜交。幾乎整年都有孢子成熟的特性，可能有利於此種交配行為。

關鍵字

促精素 ； 鬼桫欏 ； 配子體 ； 遺傳負荷 ； 繁殖生物學

並列摘要

This study focused on characteristics related to the reproductive biology of Cyathea podophylla (Hook.) Copel. gametophytes, including growth habits, sexual expression, antheridiogen, ploidy, and genetic load. Antheridium formation was not promoted when young gametophytes of C. podophylla were treated with their own mature gametophytes or those of Pteridium aquilinum (L.) Kuhn, Lygodium japonicum (Thunb.) Sw., or Ceratopteris thalictroides (L.) Brongn. Their spores did not germinate at all in dark conditions. These results indicate that there is no antheridiogen (and possibly no germinin, either) in this species. The sexual progression of their gametophytes is from male to hermaphroditic. This sexual expression is not consistent with the model of antheridiogen action, either. The chromosome number of the spore mother cells is 69(subscript Ⅱ), which indicates that the sporophytes are diploid. Because of its high genetic load, C. podophylla reproduces mainly through intergametophytic mating, especially intergametophytic crossing. The facts that spores mature almost throughout the year may facilitate this type of mating behavior.

並列關鍵字

antheridiogen ； Cyathea podophylla ； gametophyte ； genetic load ； reproductive biology