大叶蟹甲草花期种群构件生物量结构及生长分析

Biomass Structure and Growth Analysis on the Modules of Parasenecio firmus Population at Flowering Stage

为揭示大叶蟹甲草(Parasenecio firmus)花期种群构件生长和物质分配特征,该研究采用大样本随机取样方法,整株挖取30株大叶蟹甲草开花植株,对其根、茎、叶、花序梗、花序等构件的生物量及物质分配关系进行定量分析,结果表明:大叶蟹甲草种群花期株高、茎粗、叶面积、花序梗长、花序长的变异系数在19.73%~42.80%之间;构件生物量和生物量分配大小为根>茎>叶>花序>花序梗,除花序生物量变异系数超过了50%以外,其他构件生物量及生物量分配的变异系数均小于50%.大叶蟹甲草植株高度和叶面积随各构件生物量增加呈幂函数形式增长,花期各构件对株高的制约程度为个体大小>花序梗>根>叶>花序>茎;对叶面积的制约程度为个体大小>叶>花序梗>根>茎>花序.大叶蟹甲草各营养构件生物量之间存在线性函数或幂函数正相关关系,营养构件和生殖构件之间存在幂函数正相关关系.

In order to reveal the characteristics of component growth and material allocation of Parasenecio firmus at flowering stage.The biomass of the root,stem,leaf,infructescence stem and infructescence,as well as the relationship of biomass allocation were studied from 30 flowering plants of P.firmus with a large number of random samples in the field.The results showed that the variation coefficients of plant height,stem diameter,leaf area,inflorescence stem length and inflorescence length were 19.73%~42.80%.The modules biomass and biomass allocation were decreased in the order of root>stem>leaf>inflorescence>inflorescence stem.The variation coefficients of other modules biomass and biomass allocation were less than 50%except the variation coefficient of inflorescence biomass.The plant height and leaf area increased with an increase of the module biomass,which was described by a power function.The restriction degree of each module on plant height was individual size>inflorescence stem>root>leaf>inflorescence>stem;the restriction degree of leaf area was individual size>leaf>inflorescence stem>root>stem>inflorescence.There was a linear function and power function growth relationship between the biomass of the vegetative modules.There was a power function growth relationship between the vegetative modules and the reproductive modules.