431 Rajput & Baijnath – Stem anatomy of Passifora IAWA Journal 37 (3), 2016: 431–443 © International Association of Wood Anatomists, 2016 DOI 10.1163/22941932-20160145 Published by Koninklijke Brill NV, Leiden STEM ANATOMY OF SOME SPECIES OF PASSIFLORA (PASSIFLORACEAE) Kishore S. Rajput 1,* and Himansu Baijnath 2 1 Department of Botany, Faculty of Science, The Maharaja Sayajirao University of Baroda, Vadodara 390002, India 2 Ward Herbarium, School of Life Sciences, University of KwaZulu-Natal, Private Bag X54001, Durban, 4000, South Africa *Corresponding author; e-mail: ks.rajput15@yahoo.com ABSTrACT The stem anatomy of Passifora edulis, P. foetida, P. suberosa, P. subpeltata, and P. vesicaria was studied in samples collected in Durban (KwaZulu-Natal Province, South Africa) and Baroda (Vadodara, Gujarat State, India). radial stem growth in all the species is realized by a single, bidirectional vascular cambium. However, unequal activity in small segments of the cambial cylinder results in a lobed stem outline in P. foetida var. ellisonii, and a furrowed xylem cylinder in P. edulis f. edulis and P. vesicaria var. vesicaria. In P. subpeltata and P. edulis f. favicarpa the xylem remains cylindrical in outline. In all the species investi- gated, secondary xylem is diffuse-porous with growth rings indistinct or absent. In transverse view, vessels are round to oval with different diameter categories, including very narrow fbriform vessels intermixed. In P. edulis f. edulis, stems are lobed due to the unidirectional activity of the cambium in small segments. rays are mostly both narrow (1–3-seriate) and wide (multiseriate). The latter often become aggregate at some distance from the pith. Keywords: Cambial variants, lianas, aggregate rays, fbriform vessel elements, lobed stem, phloem wedges. INTrODUCTION Passiforaceae comprise about 17 genera and 575 species distributed in tropical and warm temperate regions, especially in America (Mabberley 2008), with Passifora L. (430 species) and Adenia Forssk. (97 species) being the largest genera in the family. In Durban (South Africa), all the species studied are invasive. In Gujarat (India) P. vesi- caria L. var. vesicaria occurs as an invasive species. Passifora edulis f. edulis is widely cultivated for edible fruits. The vegetative anatomy of the genus Passifora was studied extensively by Ayensu and Stern (1964). Anatomically, Passiforaceae (especially species of Adenia) are on record to have successive cambia and diffuse included phloem strands (Ayensu & Stern 1964; Hearn 2009a, b), although these reports refer to the genus Adenia and only one species of Passifora. Downloaded from Brill.com12/21/2021 07:56:33PM via free access