北美车前的种群密度对地上和地下器官形态的影响

Influences of Population Density of Plantago virginica on Its Morphological Characters of Underground and Aboveground Organs

摘要:

应用叶面分析仪、根系分析仪对北美车前(Plantagovirginica)地上和地下部分形态进行了测定,考察北美车前种群密度对植株形态学参数的影响。结果表明,在生殖生长期间,北美车前地上部分和地下部分的形态参数均受到种群密度的制约,如地上部分的叶数、叶面积、叶周长、鲜重、花穗重、花数、花穗长;地下部分的根重、根长、根部表面积和根体积。不同直径的根的形态指标受种群密度影响的程度不同,其中以对中等直径等级的根长、根表面积、根体积和根部投影面积的制约作用最大。

Abstract:

Morphological indices of aboveground and underground organs of Plantago virginica were determined using Leaf Area Analysis System (FOCTA STD 1200P) and Root Analysis System (RHIZO STD 1600+) to investigate the influence of population density on the root morphology of the plant. The indices of aboveground organs included fresh weight, leaf number, leaf length, leaf breadth, leaf length-width ratio, leaf area, leaf perimeter, spike weight, spike number, spike length, inflorescence length and flower number.The indices of underground organs included root fresh weight,root length，project area,surface area，average diameter,root volume．The morphological indices of the root were divided into nine classes according to diameter size(O mm4.5 mm)．The relationships between the indices and the population density were regressively analyzed．The morphological indices which have obvious relationships with population density are leaf num ber,leaf area，leaf perimeter，individual flesh weight，spike weight，flower number,spike length，root flesh weight，root length，root surface area，and root volume．The results showed that the influence of population density on the indices of root morphology at different diameter classes were different，and the indices of root length，root surface area，root volume，and root project area of medium diameter size were more restricted by the population density.