Leaf and Petiole Anatomy of Viburnum opulus L. (Adoxaceae)

The genus Viburnum L. comprises with four species in Turkey. The Viburnum species are known as “gilaburu, girao？lu, giligili, da？da？an, da？d？？an, geleboru, gilabada, gildar” in Turkey. In this study, the leaf and petiole anatomy of V. opulus L., are described in detail. Vascular bundle is collateral type. Leaves are bifacial and hipostomatic. There are rare eglandular trichomes on lower epidermis. Both upper and lower epidermises are covered with thick cuticle and cells are single layered. Midrib has 1-2 layered collenchyma and 4-5 layered parenchyma. Druse crystals occur in parenchyma cells. The mesophyll is consisted of 1-2 layer palisade parenchyma and 2-3 layer spongy parenchyma. Anomocytic stomata are surrounded by 4-5 ordinary epidermal cells. There are not any trichomes on the cross section of the petiole. Petiole has a total of three vascular bundles, with a big arc-shape bundle in the middle. In each corner, there are two small arc-shape bundles. Arc-shaped vascular bundles are surrounded by parenchymatous cells consisted of druses