Allelopathic effect of Aconitum pendulum (Ranunculaceae) on seed germination and seedlings of five native grass species in the Tibetan Plateau

Abstract

Aconitum pendulum is a dominant weed in bare‐land meadows on the Tibetan plateau and infected areas are very difficult to restore because of the allelopathic effects of this weed. We wanted to select native grasses to restore bare‐land meadows dominated by this toxic weed and tested the allelopathic effect of A. pendulum on seed germination and growth of roots and shoots of five native forage grasses (Elymus nutans, E. sibiricus, Poa crymophila, Festuca sinensis, Bromus inermis). Leaf exudates and high concentrations of root and stem exudates of A. pendulum inhibited seed germination as well as growth of roots and shoots. The allelopathic effect of A. pendulum leaf exudates was stronger than that of roots and stems. Poa crymophila was most resistant to inhibition by A. pendulum, whereas F. sinensis was the most susceptible grass. We conclude that P. crymophila is more suitable than the other four native grasses for sowing in pastures when restoring bare‐land meadows dominated by A. pendulum in the Tibetan plateau.