紫茎泽兰对金毛狗孢子萌发和配子体发育的化感作用

紫茎泽兰是我国外来入侵物种中危害最为严重的植物之一,广泛分布于我国西南地区,并有向东南部和中南部蔓延的趋势。本土濒危蕨类植物金毛狗的种群正受到紫茎泽兰的威胁。本研究将金毛狗的成熟孢子分别接种在含有不同浓度的紫茎泽兰根、茎、叶水提液的培养基上,观察记录金毛狗的孢子萌发和配子体发育过程。研究结果表明,紫茎泽兰根、茎、叶水提液均可对金毛狗的孢子萌发和假根生长产生抑制作用,表现为孢子萌发延迟,萌发率有所降低,假根伸长受到抑制,上述抑制作用随水提液浓度升高而增强。其中,叶水提液的抑制作用最强,随着叶水提液浓度的升高,配子体发育阶段滞后。由此可见,紫茎泽兰对金毛狗的孢子萌发和配子体发育具有化感作用。

Allelopathic effects of Eupatorium adenophorum on spore germination and gametophyte development in Cibotium barometz

Eupatorium adenopiorum is one of the most dangerous invasive plants in China.It has spread rapidly throughout south-western China and has a great potential for invading south-eastern and south-central China.Cibotium barometz is an endemic and endangered fern threatened by invasion of E.adenophorum.Allelopathy is most effective at the weakest points of the life cycle such as germinating spores and the developing gametophyte in ferns hence the allelopathic effects of E.adenophorum were evaluated on spore germination and gametophyte development of C.barometz.Spores of C.barometz were treated with root,stem,or leaf aqueous leachates of E.adenophorum and the spore germination and gametophyte development were observed and recorded.All leachates inhibited spore germination and the rhizoid growth of C.barometz and there was delayed spore germination,a reduced germination percentage and inhibition of rhizoid elongation.The inhibitory effects generally increased with increasing leachate concentrations and were most pronounced with leaf leachates.The stages of gametophyte development were delayed with increasing concentrations of leaf leachates.It is concluded that E.adenophorum has allelopathic effects on the spore germination and gametophyte development of C.barometz.