紫茎泽兰种子形态特征和萌发特性与其入侵性的关系  

Effects of seed characteristics and germination on invasiveness of Ageratina adenophora

作　　者：张丽坤[1,2] 王朔[3] 冯玉龙[3] 

机构地区：[1]中国科学院西双版纳热带植物园,勐腊666303 [2]中国科学院大学,北京100049 [3]沈阳农业大学生物科学技术学院,沈阳110866

出　　处：《生态学报》2014年第13期3584-3591,共8页Acta Ecologica Sinica

基　　金：国家自然科学基金项目(30830027;31270582);云南省自然科学资金(2009CD119)

摘　　要：利用纸皿法在不同条件下比较研究了紫茎泽兰(Ageratina adenophora)和3种同亚族本地植物种子萌发特性,同时比较了种子大小等形态特性,探讨了种子形态特征和萌发特性与紫茎泽兰成功入侵的关系。紫茎泽兰种子重量、长度、宽度以及冠毛长度均小于3种本地植物;在不同的释放高度下,紫茎泽兰种子的沉降速度低于本地植物。紫茎泽兰种子萌发温度范围广,在亚适宜的低温下,萌发率和萌发指数均高于本地植物白头婆和水泽兰。紫茎泽兰种子萌发对水和盐胁迫响应更强烈,但在适宜条件下,紫茎泽兰种子的萌发率和萌发速度均显著高于3种本地植物。这些特性可能与紫茎泽兰的入侵性有关。Ageratina adenophora is a noxious invasive weed worldwide. However, the mechanisms underlying its invasiveness are still not well elucidated. To explore the effects of seed characteristics on invasiveness of this invader,A.adenophora was compared with three native species in terms of seeds morphological traits and germination responses to environmental factors including temperatures,water,and salt. The invader was significantly lower in seed weight,length,width,and pappus length than three phylogenetically closely related native plant species. Seed settlement velocity was lower for the invader although the difference between the invader and two natives（ E. japonicum and E. chinense） was not significant. Small seeds facilitated spread of the invader. Compared with the seeds of two natives（ E. japonicum and E.chinense）,seeds of the invader germinated in a wider range of temperature. In sublow temperature（ 15 and 20 ℃）,germination ratio and germination index were higher for the invader than for two natives（ E. japonicum and E.stoechadosmum）. Responses of seed germination to water and salt stress were stronger for the invader relative to three natives. At suitable conditions（ without water and salt stress）,however,germination ratio and germination index were higher for the invader than for three natives. These traits mentioned above may facilitate successful invasion of A.adenophora.

关 键 词：紫茎泽兰 本地植物 种子形态 萌发 温度 水分 盐胁迫 入侵 

分 类 号：S451[农业科学—植物保护]