Artigo
Interploidy hybridization in sympatric zones: the formation of Epidendrum fulgens x E. puniceoluteum hybrids (Epidendroideae, Orchidaceae)
Registro en:
Ecology And Evolution. Hoboken: Wiley-blackwell, v. 3, n. 11, p. 3824-3837, 2013.
2045-7758
10.1002/ece3.752
WOS:000325486000014
WOS000325486000014.pdf
Autor
Moraes, Ana P.
Chinaglia, Mariana
Palma-Silva, Clarisse [UNESP]
Pinheiro, Fabio
Resumen
Interspecific hybridization is a primary cause of extensive morphological and chromosomal variation and plays an important role in plant species diversification. However, the role of interploidal hybridization in the formation of hybrid swarms is less clear. Epidendrum encompasses wide variation in chromosome number and lacks strong premating barriers, making the genus a good model for clarifying the role of chromosomes in postzygotic barriers in interploidal hybrids. In this sense, hybrids from the interploidal sympatric zone between E. fulgens (2n=2x=24) and E. puniceoluteum (2n=4x=56) were analyzed using cytogenetic techniques to elucidate the formation and establishment of interploidal hybrids. Hybrids were not a uniform group: two chromosome numbers were observed, with the variation being a consequence of severe hybrid meiotic abnormalities and backcrossing with E. puniceoluteum. The hybrids were triploids (2n=3x=38 and 40) and despite the occurrence of enormous meiotic problems associated with triploidy, the hybrids were able to backcross, producing successful hybrid individuals with broad ecological distributions. In spite of the nonpolyploidization of the hybrid, its formation is a long-term evolutionary process rather than a product of a recent disturbance, and considering other sympatric zones in Epidendrum, these events could be recurrent. Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Univ Estadual Campinas UNICAMP, Inst Biol, Dept Biol Vegetal, Lab Biossistemat & Evolucao Plantas, Sao Paulo, Brazil Univ Fed ABC UFABC, Programa Posgrad Evolucao & Diversidade, BR-09210580 Sao Paulo, Brazil Univ Estadual Paulista UNESP, Inst Biol, Dept Ecol, Sao Paulo, Brazil Nucleo Pesquisas Orquidario Estado, Inst Bot, Sao Paulo, Brazil Univ Estadual Paulista UNESP, Inst Biol, Dept Ecol, Sao Paulo, Brazil FAPESP: 11/22215-3 FAPESP: 12/22077-2 FAPESP: 11/00608-3 FAPESP: 09/52725-3 FAPESP: 09/17411-8 FAPESP: 09/15052-0