Fertility and sexual reproduction of invasive Asian knotweeds in Côtes d'Armor Department

Abstract

Seeds were collected from plants of the five invasive Asian knotweeds: Reynoutria japonica, R. x bohemica, R. sachalinensis, Polygonum polystachyum and Fallopia aubertii. Depending on experimental conditions, every species is able to germinate, but F. aubertii is much less fertile than the other ones. Some species germinate only in dark and cold conditions while others prefer or need light and temperature alternation. Young plants obtained from seedlings show a high morphological variability and are probably hybrids. Thus it is important to consider sexual reproduction when developing management plans.