Elementome of Orchis anthropophora and O. militaris and their hybrid from the Réserve naturelle domaniale de Lanaye (Belgium)

The main objective of this study was to determine elemental profiles of Orchis anthropophora, O. militaris and their hybrid (Orchis × spuria) in order to deduce their adaptive responses within the hybrid zone in the Réserve naturelle domaniale de Lanaye. Foliar samples of orchids were collected and subjected to monochromatic X-ray fluorescence analysis for major and trace elements. While the macro-elements predominantly accumulated in the soil and leaf samples of O. anthropophora, the highest trace element concentrations were observed in O. militaris, with intermediate values for most elements analysed in the hybrid O. × spuria. This study is the first to investigate variation in accumulation between parental species and their hybrid, with intermediate inheritance observed in Orchis × spuria. Moreover, the analysed species confirmed exclusion as the most common strategy for coping with metal-induced stress, observed in previous studies.