NeoBiota (Apr 2017)

Ant species accumulation on Lord Howe Island highlights the increasing need for effective biosecurity on islands

  • Benjamin D. Hoffmann,
  • Russell Graham,
  • Derek Smith

DOI
https://doi.org/10.3897/neobiota.34.10291
Journal volume & issue
Vol. 34
pp. 41 – 52

Abstract

Read online Read online Read online

Two species of the genus Fallopia (F. sachalinensis, F. japonica, Polygonaceae) native to Asia, and their hybrid (F. × bohemica), belong to the most noxious plant invaders in Europe. They impact highly on invaded plant communities, resulting in extremely poor native species richness. The low number of native species in invaded communities points to the possible existence of mechanisms suppressing their germination. In this study we assessed, under laboratory conditions, whether there are phytotoxic effects of the three Fallopia congeners on seed germination of three target species: two native species commonly growing in habitats that are often invaded by Fallopia taxa (Urtica dioica, Calamagrostis epigejos), and Lepidium sativum, a species commonly used in allelopathic bioassays as a control. Since Fallopia taxa form dense stands with high cover, we included varying light conditions as an additional factor, to simulate the effects of shading by leaf canopy on germination.