The ontogenetic bases for variation in ovary position in Melastomataceae

Autor(es)

Basso-Alves, Joao Paulo ^{[1, 2]} ; Goldenberg, Renato ^{[1, 3]} ; Teixeira, Simone Padua ^{[1, 2]}

Afiliação do(s) autor(es)

^[1] Univ Estadual Campinas UNICAMP, Programa Posgrad Biol Vegetal, Inst Biol, Dept Biol Vegetal, CP 6109, BR-13083970 Campinas, SP - Brazil

^[2] Univ Sao Paulo, Fac Ciencias Farmaceut Ribeirao Preto, Dept Ciencias Farmaceut, Av Cafe S-N, BR-14040903 Ribeirao Preto, SP - Brazil

^[3] Univ Fed Parana UFPR, Setor Ciencias Biol, Dept Bot, Caixa Postal 19031, BR-81531970 Curitiba, PR - Brazil

• Tipo de documento: Artigo Científico
• Fonte: AMERICAN JOURNAL OF BOTANY; v. 104, n. 8, p. 1142-1156, AUG 2017.
• Citações Web of Science: 2

Resumo

PREMISE OF THE STUDY: Although the ovary position is considered a stable character in angiosperms, Melastomataceae species have perigynous flowers in which the ovary varies from superior to inferior. Thus, we investigated the ontogenetic process involved in variation of the ovary position in Melastomataceae. We focused on histogenesis of the floral apex in search of developmental patterns for each type of ovary position. METHODS: Six species in which the ovary varies from superior to inferior were chosen: Henriettea saldanhae, Leandra melastomoides, Miconia dodecandra, Microlicia euphorbioides, Rhynchanthera grandiflora, and Tibouchina clinopodifolia. Buds and flowers were processed for surface and histological examinations. KEY RESULTS: The floral apex changes from convex to concave, resulting in a perigynous hypanthium. Cell divisions in the margins of the floral apex form an annular intercalary meristem that elevates the base of the primordia of almost all whorls. The joint growth of the carpel base with the gynoecial hypanthium originates semi-inferior ovaries in Leandra melastomoides, Miconia dodecandra, and Tibouchina clinopodifolia and inferior ovaries in Henriettea saldanhae. In Microlicia euphorbioides and Rhynchanthera grandiflora, the carpels are not affected by this hypanthial growth; flowers have a superior ovary. CONCLUSIONS: Changes in ovary position of Melastomataceae are due to intercalary meristematic activity, which is one of the main mechanisms for the origin of morphological innovations among plants. Our data illustrate the importance of the intercalary meristems in floral development, and we discuss the implications of this ontogenetic model for understanding the evolution of ovary position in Melastomataceae.s (AU)

• Processo FAPESP: 08/10793-0 - Embriologia em espécies de Miconia (Melastomataceae) com diferentes sistemas reprodutivos
• Beneficiário: Sandra Maria Carmello-Guerreiro
• Modalidade de apoio: Auxílio à Pesquisa - Regular
• Processo FAPESP: 11/02701-0 - Desenvolvimento floral em espécies de Melastomataceae Juss.
• Beneficiário: João Paulo Basso Alves
• Modalidade de apoio: Bolsas no Brasil - Doutorado