Composition and biological activity of essential oils and extracts of Solidago ssp. and their impact on their impact on radish and garden cress

This study aimed to identify the main components of essential oil (EO) produced by S. canadensis and S. gigantea and evaluate their phytotoxicity on radish (Raphanus sativa L.), and garden cress (Lepidium sativum). Plant samples were collected from 5-localities in east Slovakia (Šalgovík, Rúrky, Ľubotice, Solivar and V. Šebastová). The chemical compositions of EO were determined by GC-MS. Number of identified components in EO ranged from 39 to 52 for S. canadensis and 58 for S. gigantea. The major components differed between the 5- sampling sites. 1R-α-pinene, β-pinene, germacrene D, (-)-limonene, thymol, (+)epi-bicyclosesquiphellandrene, β-cadinene, γ-cadinene, δ-cadinene, α-muurolene, γ-muurolene, α-cubebene, β-elemene were main components (over 5% each) identified in S. Canadensis. While curlone, tumerone and δ-cadinene were identified as dominant components in S. gigantea. Two samples from Rúrky and Ľubotice were stimulatory and one sample from Solivar was inhibitory to seed germination of radish. Samples from Rúrky and V. Šebastová significantly inhibited the seed germination of garden cress. Application of EO from Rúrky and V. Šebastová on radish and EO from Ľubotice and V. Šebastová on garden cress significantly stimulated the radicle elongation. However, the EO from Solivar inhibited the radical elongation of garden cress.