紫茎泽兰（Eupatorium adenophorum Spreng），菊科多年生草本或半灌木植物，是世界性入侵杂草，也是目前危害我国最为严重的外来入侵杂草之一，对我国西南地区农业、畜牧业的良好发展以及生态环境造成了严重的危害。种子繁殖是紫茎泽兰初始建群，尤其是远距离传播的主要途径。环境对种子萌发具有决定性作用，对于物种的生存具有重要意义。因此，本试验通过室内生测法分析了紫茎泽兰种子保存时间、种内竞争及环境温度、盐分胁迫及水分胁迫等因素对紫茎泽兰种子萌发的影响。结果表明：紫茎泽兰种子寿命较长，存放2.5年的种子萌发率仍可达45.67%；紫茎泽兰种子萌发时种内竞争作用较强，能够显著降低其种子的萌发势和萌发率；紫茎泽兰种子萌发所需的温度范围较宽，在12~30℃温度范围内均可萌发，且随环境温度的升高，种子萌发越快，萌发率越高，高温（30℃/22℃）处理下种子萌发率可达到90.33%；同时发现，紫茎泽兰种子萌发对环境中的盐分浓度十分敏感，0.25%的盐质量分数即可达到种子的致死水平，1%的盐质量分数处理即可使种子完全丧失萌发能力。紫茎泽兰种子较耐水淹环境，浸水处理6 d的种子的萌发率仍高达65.68%。由此表明，紫茎泽兰种子不适应盐碱环境，而适宜于温暖潮湿的自然环境。这为探析紫茎泽兰种子萌发活动生理提供了一定的基础资料，同时，也为有效、安全的防除紫茎泽兰提供了科学依据。%Eupatorium adenophorum Spreng, an asteraceae perennial herb or subshrub, is an invasive weed around the world, as well as one of the worst invasive alien plant to China. It brings great harm to the local farm, husbandry, and the ecological environment, especially in the Southwest of China. Seed propagation is the main way for the initial establishment, especially in long-distance dispersal of E. adenophorum. Environmental factors have a decisive role on seed germination and survival of the species. The aim of this study was to investigate the effect of seed storage time, intraspecific competition, temperature, water stress and salinity on seed germination of E. adenophorum. The results showed that the germination rate is 45.67%for seed stored 2.5 years;Seed has strong intraspecific competition at germination stage, which can reduce the germination potential and the rate of germination significantly. The seed could germinate within temperature range of 12-30 ℃, and germination rate will rise along with the rising of temperature. The rate of germination is 90.33%at 30 ℃/22 ℃. Besides, the seed of E. adenophorum is very sensitive to salt concentration during germination. The half death concentration of salt is 0.25% and the seed loses the germination ability completely when the salt concentration reaches 1%. The seed is resistant to water environment. The germination rate is 65.68%after the seed soaked in water for 6 days. These suggest E. adenophorum seed do not adapt to saline environment but is suitable for a warm and humid environment. The tests provide some basic data to exploring the physiological activity of E. adenophorum During seed germination and, at the same time, may provide more effective and safer control on E. adenophorum.
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