Effects of external support on the morphological plasticity and reproductive strategies of climbing Humulus scandens

In order to discuss the influence of external support on the morphological plasticity and reproduction of Humulus scandens, the biomass distribution, morphological characteristics and propagation characteristics of each single male and female plant were determined after the wild population growth in three different ways including tree support, shrub support and no supporter. The result showed that the supporter significantly affected (P＜0.05) the stem, leaf and flower of both female and male plant. The effects of supporter on male plant were significantly higher (P＜0.05) than those on female plant for some tested indices including the length and diameter of main stem, single leaf area and ear length. However, the effects of supporter on female plant were higher than those on male plant for some tested indices including branch, leaf and flower number and length of total stem. Supporter had no effect on total biomass and stem and leaf distribution ratio of female plant whereas had significantly effects (P＜0.05) on these two indices of male plant. Supporter had a litter effect on flower distribution ratio of both female and male plant. The reproductive allocation, reproductive efficiency index, reproductive index and reproduction ratio of male plant were significantly higher (P＜0.05) than those of female plant. But supporter had smaller effect on reproductive characteristics of male plant than that of female which suggested that female plant had higher reproductive plasticity than male plant. In conclusion, the existence and types of supporter significantly affected morphological plasticity and reproductive strategy of H. Scandens.