Glandular Hairs of Salvia officinalis: New Data on Morphology, Localization and Histochemistry in Relation to Function

The structure, site and histochemistry of glandular hairs onthe vegetative and reproductive parts ofSalvia officinalis wereinvestigated by UV and conventional light microscopy and byscanning electron microscopy. Five distinct types of glandularhair (one peltate and four capitate) with different sites, secretorymodes and secretions, were identified, and a functional rolepostulated for each type. All the hair types show mixed secretions,i.e., hydrophilic and lipophilic, except type I capitate hairs,which have hydrophilic secretions only. In peltate hairs andin type II capitate hairs hydrophilic secretion prevails; inthe remaining types, lipophilic secretion dominates. The manner,time and role of erection of peltate hairs on the reproductiveorgans and the role of non-glandular hairs are also considered.Copyright 1999 Annals of Botany Company Salvia officinalis, Labiatae, rising of peltate hairs, capitate hairs, secretion, plant/insect interaction.