Effects of node position on regeneration of stolon fragments in congeneric invasive and native Alternanthera species in China

Abstract

AbstractVegetative regeneration plays an important role in the adaptation of clonal plants in frequently disturbed habitats, but few studies have compared vegetative regeneration capacity of invasive clonal plants with that of their native congeners. Vegetative regeneration capacity from shoot nodes can also be affected by the position of the nodes, but this appears little studied. We conducted a greenhouse experiment with Alternanthera philoxeroides, a highly invasive species in China, and its native congener A. sessilis to test the difference in vegetative regeneration capacity of stolon nodes at five different positions (i.e. 3rd, 4th, 5th, 6th and 7th node starting from the apex of the stolon). At the end of the experiment, we counted and harvested all regenerated plants and determined their biomass and allocation. Both species could successfully regenerate from stolon fragments and node position significantly affected regeneration rate and subsequent growth. However, the vegetative regeneration capacity of A. philoxeroides was not higher than that of A. sessilis. These results suggest that vegetative regeneration from stolon fragments may not be a trait that can explain the invasiveness of A. philoxeroides.