ANATOMICAL AND HISTOCHEMICAL CHARACTERIZATION OF EXTRAFLORAL NECTARIES OF PROCKIA CRUCIS (SALICACEAE)

Besides being, vital tools in taxonomic evaluation. the anatomy of plant secretory structures and the chemical Composition of their secretions may contribute to a More thorough Understanding, of the roles and functions of these secretory structures. Here we used standard techniques for plant anatomy and histochemistry to examine secretory structures Oil leaves at different Stages of development of Prockia crucis. to evaluate the origin and development Of the structures. and to identify the disaccharides and monosaccharides ill the exudates. Fructose, glucose. and sucrose constituted tip to 49.60% of the entire secretion. The glands were confirmed to be extrafloral nectaries (EFNs) this is the first report Of their prescence in the genus Prockia. These EFNs are globular, sessile glands. with a central concavity occurring Oil the basal and marginal regions of the leaf. The epidermis surrounding, the concavity is secretory. forming a single-layered palisade that strongly reacts with periodic acid-Schiff's reagent (PAS) and xylidine Ponceau. indicators of total polysaccharides and total proteins. respectively, in the exudate. Oil the basis of the similarity Of these glands to the salicoid teeth in Populus and Salix, We suggest that these three taxa are phylogenetically close.