Background. The process of apophytism or spreading native species to human-made habitats is one of the main elements in the creation of plant cover in anthropogenic areas. Lately, an increase of anthropogenic localities with valuable flora (rare and law protected species) has been observed. Apophytes are also members of the family Orchidaceae, especially from the genus Epipactis. The aim of the study was to i) determine and compare the phenotypic variation of E. helleborine plants in anthropogenic and natural habitats, ii) compare the genome size estimation of plants growing in natural and anthropogenic habitats. The results reported in this study may indicate that a habitat influences morphological characteristics of plant species.
Methods. The research was carried out in Poland from 2011 to 2013. The study sites were located in three different geographical regions: from the Białowieża Primeval Forest, Northern East Poland, through Central Poland, to the Lower Silesia Province, Southern West Poland. We investigated eight populations of E. helleborine: four from natural habitats and four from anthropogenic habitats. Biometrical analyses were performed on shoots and flowers. The flowers were characterised by 25 biometric features and measured using a Nikon SMZ 800 binocular, microscopic Moticam-1SP cameras and the MIPlus07 program (Conbest Co.). The nuclear DNA content was determined in fresh and young leaves of E. helleborine, collected from eight populations.
Results. We observed that in anthropogenic populations: i) shoots were higher than shoots from natural populations, ii) flowers differed significantly in terms of ten biometric features between habitats, iii) the genome size differed significantly between the plants growing in natural and anthropogenic habitats.
Discussion. According to some researchers, the presence of phenotypic plasticity and the occurrence of ecotypes are adaptation strategies of plants to environmental changes. In our opinion, in the case of the studied anthropogenic habitats (roadside) in which the E. helleborine populations grew, we can talk about ecofen due to the often repeated set of characteristic features. i.e.: high shoots, long inflorescence and long, broad leaves. We agree, however, that it is difficult to isolate a taxonomic unit for ecofen due to the lack of experimental research.