Potential allelopathic activity of Sidertis italica (Miller) Greuter rt Burdet essential oil

Abstract

Sideritis italica (Miller) Greuter et Burdet is a widespread Mediterranean Lamiacea. Essential oils from S. italica flowerheads and leaves were extracted by hydrodistillation and then tested for their potential allelopathic activity against Raphanus sativus L. (Magnoliophyta) and the moss Tortula muralis (Hedw.) (Bryophyta), two organisms already tested for allelopathy, and against two bryophytes growing in the same environment as S. italica: the moss Bryum capillare Hedw. and the liverwort Lunularia cruciata (L.) Dum. For R. sativus, we considered seed germination and root and epicotyl growth. For the mosses, we used spore germination and protonemata development, while for the liverwort, we studied thallus and rhizoid growth as well as gemma development. Leaf oil was more active than flowerhead oil. The leaf essential oil caused a decrease in the percentage of seed germination and inhibition of root and epicotyl growth in R. sativus. Furthermore, it caused a strong inhibition of spore germination and protonemal development in both the mosses T. muralis and B. capillare and caused inhibition of gemma development and browning and inhibition of apical growth in the thallus of L. cruciata