Plant invasion is a dual phenomenon: the role of the plant and its environment

Abstract

In many cases, human interventions into pristine nature have been accompanied by species invasions, which certainly hamper the effort to protect and restore habitats. Alien plant invasion affects the diversity and stability of the local community. The EU Biodiversity Strategy for 2030 has set the challenge of controlling invasive aliens that have already become widespread. Data on alien species show that plant invasions are caused by a complex combination of characteristics of invasive species (invasiveness) and characteristics of invaded environment (invasibility). The first target of invasive alien species regulation is the most aggressive invaders. Small balsam (Impatiens parviflora from Balsaminaceae) could be classified in this category. Numerous studies have focused on I. parviflora interactions with neighboring herbaceous species. Phytocenological data were mostly associated with either environmental properties of the sites or with geographical, morphological, and physiological properties of I. parviflora populations, but the relationship with molecular features has been poorly investigated. The objective of our study was to evaluate the genetic diversity of Lithuanian populations of highly invasive Impatiens parviflora by set of molecular markers and to relate molecular data to biotope features defined by employing neighboring species of herbaceous plants. In total, 138 herbaceous species were registered. Bayesian analyses of molecular data demonstrated many genetic clusters. Our results suggest multiple introductions of I. parviflora into Lithuania. The molecular diversity of populations significantly correlated with the total coverage by herbaceous plants in the sites. The variability of study sites was most related to the coverage of herbaceous plants and least related to the molecular features of I. parviflora populations.