Abstract: The study aimed to collect morphological data of
secretory structures that contribute to taxonomy of Indigofera. Detail
features of trichomes occurrence in vegetative and reproductive
organs of Indigofera wightii Grah. ex Wigh & Arn., a species
traditionally used as source of indigo to dye “Thaisongdam” clothing
were investigated. Examination through light microscopy and
scanning electrom microscopy were done. Non secretory, T-shaped
trichomes appeared throughout surfaces of stems, leaves, flowers and
fruits. Secretory or glandular trichomes occurred in two types; one
has big cylindrical head and short peduncle, distributed on adaxial
surface of sepals and around the pedicel, whereas another possesses
smaller cylindrical head but long peduncle. The latter was found on
apical surface of immature pods. No phenolic and lipophilic
compounds were detected from these glands.