【摘要】 竹叶眼子菜 (Potamogeton malaianus)、微齿眼子菜 (Potamogeton maackianus)、苦草 (Vallisneria spiralis)、穗花狐尾藻 (Myriophyllum spicatum)、黑藻 (Hydrilla verticillata)是长江中下游湖泊主要的沉水植物。在栽培条件下 ,它们的无性繁殖速率 (单位时间内新增个体数 )大小顺序为黑藻 >微齿眼子菜 >竹叶眼子菜 >苦草 >穗花狐尾藻。同时采用抛掷实验的方法观察研究了这 5种沉水植物及其无性繁殖体的存活和生根情况 :完整植株存活率为黑藻 >穗花狐尾藻 >微齿眼子菜 >竹叶眼子菜 >苦草 ,无性繁殖体部分存活率为黑藻 >苦草 >穗花狐尾藻 >微齿眼子菜 >竹叶眼子菜。生根能力和其存活时间长短相关 ,而且生根能力与存活率大小基本一致。在实验中 ,只有穗花狐尾藻的断枝存活率和生根能力存在差异 ,故无性繁殖体生根能力为黑藻 >苦草 >微齿眼子菜 >竹叶眼子菜 >穗花狐尾藻更多还原

【Abstract】 Potamogeton malaianus, P. maackianus, Vallisneria spiralis, Myriophyllum spicatum and Hydrilla verticillata are common dominant submersed macrophytes in lakes of the middle and lower reaches of the Changjiang River. W e investigated the regeneration abilities of these five species in growing expe riment. The species can be arranged in order of increasing rate of production of asexual propagules: H. verticillata > P. maackianus > P. malaianus > V. spira lis > M. spicatum. Rates of survival of plants were measured at two scales: 1) the whole plant, in which survival of H. verticillata > M. spicatum > P. maac kianu > P. malaianus > V. spiralis, and 2) vegetative propagules: H. vertici llata > V. spiralis > M. spicatum > P. maackianus > P. malaianus. In addition to the fragment of Myriophyllum spicatum, colonization ability (root growth rate) of each species was correlated with its survival rate and the ranks order of colonization ability in the 5 species and their propagules were identical to that of their rates of survival.更多还原