水蓼花大小在花序和个体上的变化及其与数量权衡关系研究

Flower size variation at the inflorescence and individual levels and its trade-off with flower number in Polygonum hydropiper(Polygonaceae)

关键词:  水蓼  花大小  花数量  植物大小  权衡

Key words:  Plygonum hydropiper  flower size  flower number  plant size  trade-off

摘要:

探讨一年生植物水蓼花大小在花序上和个体上的变化及花大小与花数量的权衡关系。在54株植物个体上随机选取一花序,在花序的基部、中部和顶部各选取1～2朵花,花大小(生物量)以基部最大(0.851 mg),顶部最小(0.715 mg),可能是由结构效应引起的。在每个体上随机采集4～20朵花,以其均值表示植物个体的花大小,花大小不随植物个体大小变化而变化。花朵展示和总花数均随个体增大而增加。在控制植物个体大小(地上部分营养器官生物量)后,没有发现花朵展示或花数量与花大小之间的权衡关系,表明个体资源水平的差异可能掩盖了花数量与大小间的权衡关系。

Abstract:

Flower size variation at the inflorescence and individual levels and its trade-off with flower number were evaluated in annual herb,Polygonum hydropiper(Polygonaceae). One or two flowers were randomly sampled from three relative positions(basal,middle,distal)within an inflorescence of fifty-four plants,average flower size(mass)was largest at the basal positions(0.851 mg)and smallest at the distal positions(0.715 mg),probably due to architectural effects. Four to twenty flowers were randomly sampled from each individual,average flower size did not change with plant size(aboveground vegetative biomass). Both floral display size and total flower production increased with plant size. No trade-off between display size or total flower production and flower size was detected at the plant level both before and after controlling for plant size(aboveground vegetative biomass)statistically,probably due to variations in resource availability.