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作 者 ：李洁琳;尹黎燕;陈媛媛;顾舒平;李伟;

期 刊 ：武汉植物学研究 2010年 28卷 3期 页码：330-335

关键词：水生植物；种子萌发；聚集萌发；密度效应；

Keywords:Aquatic plant, Seed germination, Clustering effect, Densityeffect,

摘 要 ：

以10种常见水生植物的种子为材料,研究了种子聚集对其萌发的影响.结果表明,水鳖科植物种子萌发对聚集的响应多为正效应:海菜花(Ottelia acuminata)、出水水菜花(O.emersa)、密刺苦草(Vallisneria denseserrulata)、水鳖(Hydrocharis dubia)和无尾水筛(Blyxa aubertii)种子聚集后其最终萌发率显著提高;苦草(V.natans)和刺苦草(V.spinulosa)种子聚集后最终萌发率虽然没有显著提高,但是其萌发速率得到显著提高.种子聚集对穗花狐尾藻(Myriophyllum spicatum)的种子萌发有显著的抑制作用,而对穿叶眼子菜(Potamogeton perfo-liatus)和水麦冬(Triglochin palustre)的种子萌发无显著作用.水生植物的种子聚集萌发特性可能与其繁殖策略有关.水鳖科植物多进行有性繁殖或者有性繁殖比例较大,其种子也由于粘性物质的包裹为聚集分布,在野外聚集萌发的大量植株形成一个单一物种的斑块,这有利于迅速占领新生境.而穗花狐尾藻、穿叶眼子菜和水麦冬种群维持和扩张基本依靠克隆繁殖.

Abstract:This article investigated the clustering effect on seed germination for 10 aquatic plants.Results showed that the response of seed germination to seedclustering in Hydrocharitaceae was mostly positive,with the seed germination rates of Ottelia acuminata,O.emersa,Vallisneria denseserrulata,Hydrocharis dubia,and Blyxa aubertii significantly improved.The germination rates of V.natans and V.spinulosa were significantly promoted when seeds clustered.Conversely,the seed germination rate of Myriophyllum spicatum was significantly inhibited and no significant difference was found in Potamogeton perfoliatus,Triglochin palustre when seeds were clustered.The clustering effect on seed germination may be related to their reproductive strategy.Of these species,population expansion of Hydrocharitaceae mainly depends on seeds or sexual reproduction accounting a larger proportion in the reproduction allocation.Their seeds are often clustered because of the gelatinous matter in the fruit.When these seeds meet suitable conditions,they produce a patch area of single species and occupy the habitat rapidly.Contrarily,for M.spicatum,P.perfoliatus and T.palustre,whose expansion mainly depends on clonal propagation,the response of seed germination to seedclustering showed a negative or no significant effect.

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