Comparison of Growth Traits between Invasive Species Bidens pilosa and Its Indigenous Congener B. biternata under Different Light and Water Conditions

Abstract:

In order to understand invasive mechanism, the growth traits of Bidens pilosa L. and native species B. biternata Lour. under different light and water conditions were compared by pot experiment in greenhouse. The results showed that both species appeared great plasticity to various light and water environments. However, the height, total leaf area and biomass of B. pilosa under favorable conditions, and the specific leaf area and leaf area ratio under unfavorable conditions were higher than those of native species B. biternata. Meanwhile, except for leaf area ratio or leaf mass ratio, the plasticity indices of all parameters of B. pilosa were greater than those of native species. These indicated that B. pilosa had greater phenotypic plasticity and invasion adaptability, which promoted successful invasion of B. pilosa.