Effects of extracts from various parts of invasive Solidago species on the germination and growth of native grassland plant species

Abstract

Allelopathy is an important factor influencing whether an invasive plant species can become successfully established in a new range through disrupting the germination and growth of native plant species. Goldenrods (Solidago species) are one of the most widespread invasive taxa in Central Europe of North American origin. Owing to their high environmental impact and wide distribution range, invasive Solidago species should be controlled in Europe, and the areas invaded by them should be restored. Numerous studies have reported the allelopathic effects of Solidago gigantea and Solidago canadensis, but the results are inconsistent regarding differences in the allelopathic effects of particular plant parts and in the sensitivity to Solidago allelopathic effects among native species as well as between the two invasive species themselves. In this study, we aimed to analyse the effect of water extracts from S. canadensis and S. gigantea parts (roots, rhizomes, stems, leaves, and inflorescences) on the germination and initial growth of seedlings of 13 grassland species that typically grow in Central Europe. The tested grassland species differed in susceptibility to Solidago allelopathy, with the most resistant species being Schedonorus pratensis, Lolium perenne, Trifolium pratense, Daucus carota and Leucanthemum vulgare. The inhibitory effect of 10% water extracts from leaves and flowers were stronger than those from rhizomes, roots, and stems without leaves, regardless of the Solidago species. Our study results imply that reducing the allelopathic effect of Solidago during habitat restoration requires removal of the aboveground parts, including fallen leaves. The allelopathic effects of roots and rhizomes seem to be of secondary importance.

The Invasive Alien Plant Solidago canadensis: Phytochemical Composition, Ecosystem Service Potential, and Application in Bioeconomy

“…Others found that S. canadensis affects the growth and seed germination of tested plants (Lactuca sativa, Morus alba, Pharbitis nil, Brassica campestris, Lepidium sativum, and others) [71][72][73]. The allelopathic effect was also observed in the research by Perera et al [74] where S. canadensis leaf and flower extracts caused lower germination and seedling growth of different grassland plant species such as Festuca rubra L., Phleum pratense L., Poa pratensis L., Lotus corniculatus L., Trifolium repens L., and Silene flos-cuculi (L.) Greuter & Burdet.…”

Effect of litter decomposition on mowing and plant composition change during Solidago stand restoration

“…Before litter decomposition, S. canadensis litter exhibited a stronger allelopathic effect than native litter on lettuce (Lactuca sativa) (He et al, 2022). Our previous study on the response of native grassland species to allelopathic species revealed that leaves and flowers of Solidago species have stronger inhibition effects than stems, roots, and rhizomes (Perera et al, 2023). Therefore, Solidago allelopathy will alter the neighbouring species which may change the decomposition of litter.…”

Multiple invasive species affect germination, growth, and photosynthesis of native weeds and crops in experiments

“…In such young plants, the roots are much smaller than the green parts. In addition, extracts from the green parts of goldenrods affect other plants more than those from the roots 38 .…”

“…Note that we use the term “weed” for all non-crop plants, as these plants are not wanted by farmers as they lead to crop contamination. Both goldenrods and walnuts have been reported to have allelopathic effects on other plant species 34 – 36 , 38 . Also, both goldenrod and walnut often co-occur with crops 15 , 16 and weeds 4 , 14 in agricultural landscapes, and agricultural activities commonly incorporate damage and transportation of both plant tissues into the soil.…”