In: Phyton, 52 Fasc. 2 (2012), S. 227-244, with 6 figures

Key words: Lavandula × intermedia Emeric ex Loisel. ,Budrovka‘, Lavandula angustifolia Mill.; Lamiaceae. – Trichomes, histochemistry, phenolic compounds, essential oil.

Summary

Blažekovic B., Stabentheiner E., Brantner A. & Vladimir-Kneževic S. 2012. A comparative study on glandular trichomes of Lavandula × intermedia ,Budrovka‘ and L. angustifolia. – Phyton (Horn, Austria) 52 (2): 227–244, with 6 figures.

Lavandula species have a long history of use in traditional medicine and fragrance industry and Croatian’s lavender industry bases on the cultivar Lavandula × intermedia Emeric ex Loisel. ,Budrovka‘. This taxon was investigated in comparison to L. angustifolia Mill. studying morphology, trichome types and trichome distribution by light and scanning electron microscopy and by applying thin layer chromatography for phytochemical analyses. Morphological characteristics clearly distinguished L. × intermedia ,Budrovka‘ from L. angustifolia. Three distinct classes of trichomes (non-glandular trichomes, peltate and four types of capitate glandular trichomes) were observed on leaves and inflorescence of both taxa. Trichomes showed distinct organ specific differences concerning occurrence and density but no taxa specific differences could be observed. Long stalked capitate trichomes with distinct knobs formed by the upper stalk cells, a final neck cell and a unicellular head, were reported for the first time as the exclusive glandular trichome type found on the inner surface of the corolla. Histochemical tests identified both lipophilic and phenolic substances as main products secreted by the glandular trichomes. Furthermore, comparative TLC fingerprint profiles of individual plant parts of both taxa regarding the presence of flavonoids and essential oil components were established.