Evolution of the outer ovule integument and its systematic significance in Melastomataceae

Author(s)

Souza Caetano, Ana Paula ^{[1, 2]} ; Basso-Alves, Joao Paulo ^[1] ; Cortez, Priscila Andressa ^[3] ; Garcia De Brito, Vinicius Lourenco ^[4] ; Michelangeli, Fabian Armando ^[5] ; Reginato, Marcelo ^[5] ; Goldenberg, Renato ^[6] ; Carmello-Guerreiro, Sandra Maria ^[7] ; Teixeira, Simone Padua ^[8]

Affiliation

^[1] Univ Estadual Campinas, Inst Biol, Programa Posgrad Biol Vegetal, Campinas, SP - Brazil

^[2] Univ Fed Uberlandia, Inst Biol, Programa Posgrad Ecol & Conservacao Recursos Nat, Uberlandia, MG - Brazil

^[3] Univ Estadual Santa Cruz, Dept Ciencias Biol, Ctr Microscopia Eletron, Ilheus, BA - Brazil

^[4] Univ Fed Uberlandia, Inst Biol, Uberlandia, MG - Brazil

^[5] New York Bot Garden, Inst Systemat Bot, Bronx, NY 10458 - USA

^[6] Univ Fed Parana, Dept Bot, Ctr Politecn, Setor Ciencias Biol, Curitiba, Parana - Brazil

^[7] Univ Estadual Campinas, Inst Biol, Dept Biol Vegetal, Campinas, SP - Brazil

^[8] Univ Sao Paulo, Fac Ciencias Farmaceut Ribeirao Preto, Dept Ciencias Farmaceut, Ribeirao Preto, SP - Brazil

• Document type: Journal article
• Source: Botanical Journal of the Linnean Society; v. 186, n. 2, p. 224-246, FEB 2018.
• Web of Science Citations: 1

Abstract

Ovule characters have been shown to be informative at higher taxonomic levels and are therefore of interest in angiosperm systematics. In this study, we aimed to describe the evolution of the outer ovule integument thickness in Melastomataceae and to evaluate its systematic and biological significance. This character was investigated in 137 species, and data from the literature were compiled for 22 additional species, totalling 159 taxa. Integument origin was studied in selected species to clarify whether different conditions were associated with different ontogenetic - origins. The most recent common ancestor of Melastomataceae probably had an ovule with a two-cell-layered outer - integument. A multilayered outer integument evolved independently at least six times in the family. Moreover, - reversals to the two-cell-layered plesiomorphic condition have also occurred more than once. The two-cell-layered and - multilayered outer integuments have different ontogenetic origins, enhancing the taxonomic usefulness of this character. The thickness of the outer ovule integument is of systematic significance in Olisbeoideae, Rupestrea, Melastomateae and Miconieae. The multilayered outer integument may have some adaptive significance for Miconieae and Mouriri, groups with endozoochoric fleshy fruits. Evidence of a multiplicative testa was observed in a few species with both types of integuments and it may be associated with a massive seed coat found in large seeds. (AU)

• FAPESP's process: 10/15077-0 - Apomixis, sexuality, polyploidy and pollen viability in the Neotropical tribe Miconieae (Melastomataceae)
• Grantee: Ana Paula de Souza Caetano
• Support Opportunities: Scholarships in Brazil - Doctorate
• FAPESP's process: 08/10793-0 - Embryology in Miconia (Melastomataceae) species with different reproductive systems
• Grantee: Sandra Maria Carmello-Guerreiro
• Support Opportunities: Regular Research Grants
• FAPESP's process: 13/08945-4 - Calcium oxalate crystals in endothecium layer of Melastomataceae - a morphological marker with systematic implications in family
• Grantee: Ana Paula de Souza Caetano
• Support Opportunities: Scholarships abroad - Research Internship - Doctorate