摘要
主要研究了喜旱莲子草对光照强度(Light intensity,LI)、植株密度(Plant density,PD)以及两者间交互作用的可塑性响应,探讨了可塑性是否能提高其入侵能力.实验室分别在低、中、高光照强度下人工种植喜旱莲子草,且每个光照强度下又设置3个低、中、高种植密度(每箱分别种植4、8、12株喜旱莲子草).6周后,采集植株并测量其干重等生理生态指标.结果表明,以LI和PD作为单因子进行研究时,其对喜旱莲子草生理生态指标的影响均达到显著水平(p<0.05);与对照(100%LI和低PD)相比,单株喜旱莲子草的生物量在60%LI下最大;低密度促进茎的生长,中密度最适宜叶的生长,而高密度则有利于根的生长.在LI×PD共同作用下,叶重、叶重比、比根长等指标与对照相比亦有显著性差异(p<0.05);在低光照强度×中种植密度条件下,喜旱莲子草生理生态指标明显高于其他条件下的.低光照强度、中种植密度在一定程度上增强了喜旱莲子草的入侵能力.
Our objectives were to investigate the effects of light intensity（LI）,plant density（PD）and their interac-tion on the plasticity of A.Philoxeroides,and examine whether plasticity could promote the invasiveness of A.Phil-oxeroides.In a controlled factorial experiment,we grew artificial populations of A.philoxeroides in low,moderate and high PD（4,8 and 12 individuals per container,respectively） under low,moderate and high LI.All plants were harvested after six weeks and measured the dry mass for each plant part.Both LI and PD significantly affected ecophysiological traits of A.philoxeroides（p0.05）.Under 60 % LI,the biomass of each single A.philoxeroides plant was the maximum compared to the control（100 % LI and low PD）.As a result,low PD promoted the growth of stem,and moderate PD was suitable for the leaf growth,while root length was the highest under high PD.The interaction of LI and PD had affected the leaf mass,leaf mass ratio,and root length ratio etc.of A.philoxeroides significantly（p0.05）.The biomass and morphological traits of A.philoxeroides were the highest under low LI and moderate PD.Low LI and moderate PD could strengthen the invasiveness of A.philoxeroides.
出处
《河南科学》
2011年第2期159-164,共6页
Henan Science
关键词
喜旱莲子草
入侵能力
可塑性
光照
植株密度
alternanthera philoxeroides
invasiveness
light Intensity（luminance）
plasticity
plant density
