Interspecific anatomical differences result in similar highly flexible stems in Bignoniaceae lianas

Author(s)

Gerolamo, Caian S. ^[1] ; Nogueira, Anselmo ^[2] ; Pace, Marcelo R. ^[3] ; Angyalossy, Veronica ^[1]

Affiliation

^[1] Univ Sao Paulo, Dept Bot, Inst Biociencias, Rua Matao 277, BR-05508090 Sao Paulo, SP - Brazil

^[2] Univ Fed ABC, Ctr Ciencias Nat & Humanas CCNH, Rua Arcturus 03, BR-09606070 Sao Bernardo Do Campo, SP - Brazil

^[3] Univ Nacl Autonoma Mexico, Dept Bot, Inst Biol, Circuito Zona Deport S-N Ciudad Univ, Mexico City 04510, DF - Mexico

• Document type: Journal article
• Source: AMERICAN JOURNAL OF BOTANY; v. 107, n. 12 DEC 2020.
• Web of Science Citations: 0

Abstract

Premise Lianas are intriguing forest components in the tropics worldwide. They are characterized by thin and flexible stems, which have been related to a unique stem anatomy. Here, we hypothesized that the anatomical diversity of lianas, varying in shapes, proportions, and dimensions of tissues and cell types, would result in different stem bending stiffnesses across species. To test this hypothesis, we chose four abundant liana species of central Amazonia belonging to the monophyletic tribe Bignonieae (Bignoniaceae) and compared their basal stems for their anatomical architectures and bending properties. Methods Measurements of anatomical architecture and bending stiffness (structural Young's modulus) included light microscopy observations and three-point bending tests, which were performed on basal stems of eight individuals from four Bignonieae species. All analyses, including comparisons among species and relationships between stem stiffness and anatomical architecture, were performed using linear models. Results Although the anatomical architecture of each species consists of different qualitative and quantitative combinations of both tissues and cell types in basal stems, all species analyzed showed similarly lower bending stiffnesses. This similarity was shown to be directly related to high bark contribution to the second moment of area, vessel area and ray width. Conclusions Similar values of stem bending stiffness were encountered in four liana species analyzed despite their variable anatomical architectures. This pattern provides new evidence of how different quantitative combinations of tissue and cell types in the basal stems of lianas can generate similarly low levels of stiffness in a group of closely related species. (AU)

• FAPESP's process: 18/06917-7 - LIANAS: an integrative approach from an anatomical perspective
• Grantee: Veronica Angyalossy
• Support Opportunities: Regular Research Grants
• FAPESP's process: 13/10679-0 - Ontogenetic, functional and evolutionary aspects of the cambial variants in tracheophytes
• Grantee: Veronica Angyalossy
• Support Opportunities: BIOTA-FAPESP Program - Regular Research Grants