A new anatomical interpretation for abaxialization in unifacial leaf blade of stone plants (Aizoaceae, Caryophyllales)

Author(s)

Ogura, Aline S. ^[1] ; Hernandes-Lopes, Jose ^{[1, 2]} ; Melo-De-Pinna, Gladys F. A. ^{[1, 3]}

Affiliation

^[1] Univ Sao Paulo, Inst Biociencias, Dept Bot, CP 11461, BR-05422970 Sao Paulo - Brazil

^[2] Inst Biociencias, Genom & Transposable Elements Lab, Cidade Univ, Rua Matao 277, BR-05940060 Sao Paulo, SP - Brazil

^[3] Inst Biociencias, Lab Anat Vegetal, Rua Matao 277, Sao Paulo, SP - Brazil

• Document type: Journal article
• Source: BRAZILIAN JOURNAL OF BOTANY; v. 41, n. 3, p. 751-764, SEP 2018.
• Web of Science Citations: 0

Abstract

Unifacial leaves are described in different angiosperm groups, especially in monocotyledons, which show anatomical and molecular evidence of an abaxialization process. Among the structural characters, the anatomy of epidermis and growth tissues has been reported. Special focus has been given to vascularization patterns, such as the presence and organization of peripheral vascular bundles. In the Aizoaceae, peripheral vascular bundles exhibit two patterns: exoscopic and endoscopic bundles; however, studies including an ontogenetic approach with evidence for a unifacial condition in the group are lacking. We investigated eleven Ruschioideae species, including members of two tribes (Ruschieae and Dorotheantheae), which present flat and terete leaves. Our results show that all leaves present a bifacial leaf base, with xylem cells oriented toward the adaxial face present in collateral vascular bundles. However, the occurrence of peripheral endoscopic vascular bundles in the leaf blade in all terete leaves demonstrates a unifacial condition which is present only at the leaf blades. Based on ontogenetics studies, we demonstrate that the peripheral endoscopic bundles begin their differentiation in the abaxial side of the leaf primordia, suggesting the occurrence of an abaxialization process during leaf blade development. (AU)

• FAPESP's process: 15/15158-4 - ANATOMICAL AND MOLECULAR STUDIES OF THE LEAF DEVELOPMENT
• Grantee: Gladys Flávia de Albuquerque Melo de Pinna
• Support Opportunities: Regular Research Grants
• FAPESP's process: 11/04286-0 - LEAF ONTOGENESIS IN RUSCHIOIDEAE (AIZOACEAE)BASED ON MORPHOLOGICAL PATTERNS AND PHYLOGENY
• Grantee: Aline Siqueira Nunes
• Support Opportunities: Scholarships in Brazil - Master