Study of Floral Epidermal Features in Gmelina arborea Roxb. (VERBENACEAE)

Gmelina arborea Roxb. is a medium sized, unarmed, deciduous tree with whitish gray smooth bark. The plant is also important medicinal. Its flowers are showy, 2.5–3.5 cm long, brownish-yellow usually in small, opposite decussately arranged small cymes of about three flowers along the axis of a densely fulvous-hairy terminal panicles. Floral epidermal features including nature of epidermal cells, stomata and trichomes along with their dimensions of all floral parts are studied. Epidermal cells are found straight walled in peduncle, bract, stamen, carpel and fruit with cuticular striations in staminal cells, broadly sinuate in calyx, broadly and deeply sinuate in adaxial and abaxial surfaces of corolla lobes respectively. Peduncle, fruit are astomatic and bracts, calyx and corolla lobes are hypostomatic. They are anomocytic in bract, anomocytic, diacytic and paracytic in calyx and anomocytic and very occasional abaxially on corolla lobe. Trichomes are of two types non-glandular and glandular, which vary, in minute details on different parts. Unique multiseriate glandular trichomes are exclusively found on filaments. Floral trichomes are found species specific and suggestive of their functional significance. Gmelina arborea, floral trichomes, stomata, epidermal cells, anomocytic.