摘要
紫茎泽兰是我国危害最严重的外来入侵物种之一,为探讨表型可塑性和局域适应在其入侵中的作用,在高、低海拔的两个样地内,测定了来自云南南部640～2450m海拔范围的6个种源的紫茎泽兰种群的株高、冠宽、分枝数和高温半致死温度(HSLT)。结果表明,在高海拔样地,各种群紫茎泽兰株高、冠宽、分枝数和HSLT(2130m的哀牢山种群除外)均显著低于在低海拔样地,紫茎泽兰各种群的株高、冠宽和分枝数的可塑性指数(0.881～0.975)均较大,而HSLT的可塑性(0.052～0.200)较小。无论在高还是低海拔样地,紫茎泽兰的株高、冠宽和分枝数在种群间的差异均不显著,而HSLT在种群间的差异达极显著水平,表现出明显的遗传分化,但其在种群间的差异仍小于其在样地间的差异。在高海拔样地,紫茎泽兰各种群的分枝数与种源海拔呈显著正相关;在低海拔样地,紫茎泽兰的HSLT与种源海拔呈显著负相关,表现出明显的局域适应特征。表型可塑性和局域适应均与紫茎泽兰的入侵有关,但前者的作用可能更大。
Phenotypic plasticity and local adaptation are two strategies with which plants acclimate to heterogeneous habitats,facilitating alien species invasions.Eupatorium adenophorum Sprengel is one of the worst invasive species in China.To explore the roles of phenotypic plasticity and local adaptation in E.adenophorum invasion,seedling height,canopy width,branch number and high semi-lethal temperature（HSLT）were measured for six E.adenophorum populations of different altitude origins（640-2450 m）at two common gardens located at high（1400 m）and low（2450 m）altitude,respectively.Seedling height,canopy width,branch number and HSLT（except population of 2130 m origin）were significantly lower at the high altitude garden than at the low altitude garden.The plasticity indices of seedling height（0.930-0.956）,canopy width（0.881-0.952）and branch number（0.962-0.975）were relatively high,while the plasticity index of HSLT was low（0.052-0.200）.At both gardens,the differences among E.adenophorum populations of different origins in seedling height,canopy width and branch number were not significant（P 〉 0.05）,while the difference in HSLT was extremely significant（P 〈 0.01）,showing genetic differentiation.However,the difference in HSLT among the studied populations was still smaller than that between gardens.At high altitude garden,branch numbers of different E.adenophorum populations were positively correlated with altitudes of origins.At low altitude garden,HSLT was negatively correlated with altitude of origin.The above correlations indicate local adaptation of the two variables.Our results indicate that phenotypic plasticity might be more important in E.adenophorum invasion in different altitude habitats than local adaptation,while both of them contribute to E.adenophorum invasion.
出处
《生态学报》
CAS
CSCD
北大核心
2009年第4期1940-1946,共7页
Acta Ecologica Sinica
基金
云南省应用基础研究计划资助项目
国家自然科学基金资助项目(30670394)
中国科学院知识创新工程重大资助项目(KSCX1-SW-13-0X-0X)
关键词
表型可塑性
遗传分化
局域适应
生长
高温半致死温度
紫茎泽兰
入侵
phenotypic plasticity
genetic differentiation
local adaptation
growth
high semi-lethal temperature
Eupatorium adenophorum
invasion
