水分和温度对紫茎泽兰幼苗生长的影响

比较2个水分和3个温度梯度条件下,中国和墨西哥两种群紫茎泽兰（Eupatorium adenophorum Spreng）的形态、生物量分配和光合色素的可塑性反应,探讨两种群在幼苗阶段生长特点及入侵潜力。结果表明：（1）各温度水分处理下墨西哥种群株高、叶片数、总叶面积、总生物量、叶生物量比、叶根比、总叶绿素较高,中国种群根长、根生物量、根冠比较高。表明墨西哥种群在适宜的环境条件下比中国种群有更高的资源捕获能力,而中国种群对干旱和低温条件有更好的适应能力。（2）两种群紫茎泽兰对水分响应显著,100%水分下总叶面积、平均叶面积、总生物量、叶生物量比、叶面积比、叶根比、总叶绿素均高于50%水分条件。对温度响应显著,尤其20℃时,中国种群根长,墨西哥种群总叶面积,100%水分下平均叶面积、总生物量、叶生物量比、叶根比5,0%水分下根生物量比,均达最高值。两种群喜湿润的环境,温度20℃时生长较好。

Effects of Moisture and Temperature on Seedling Growth of Eupatorium adenophorum

The responses of morphology,biomass allocation and photosynthetic pigments to two water contents and three temperatures gradientes of two populations of Eupatorium adenophorum from China and Mexico were compared,to explore the growth characteristics and invasive potential at the seedling stage.Mexican population was significantly higher in height,leaf number,total leaf area,total biomass,leaf biomass,leaf root ratio,total chlorophyll,while Chinese population was significantly higher in root length,root biomass,and root to shoot ratio.Indicating Mexican population holds stronger resource captruing capacity.The two populations of E.adenophorum responded significantly to moisture and temperature,with total leaf area,the average leaf area,total biomass,leaf biomass,leaf area ratio,leaf root ratio,and total chlorophyll significantly higher under 100% moisture than those under 50% moisture,and the average leaf area,total biomass,leaf biomass,leaf root ratio under 100% moisture,the root biomass ratio under 50% moisture,root length of Chinese population,total leaf area of Mexican population,up to a maximum value at 20 ℃.Both of populations favored humid environment,and grew better at 20 ℃.