Estudos taxonomicos no complexo Kielmeyera coriacea Mart. &Zucc (Clusiaceae) / Taxonomic studies in the Kielmeyera coriacea Mart. &Zucc complex (Clusiaceae)

AUTOR(ES)
DATA DE PUBLICAÇÃO

2009

RESUMO

Kielmeyera Mart. &Zucc. (Clusiaceae) has 47 species and its more recent revision was based on morphological characters. The Coriaceae (Wawra) Saddi series is distinguished from the other series mainly by its coriaceous leaves and shrub/tree habit. In its latest circumscription, the series has two species, K. coriacea, with two subspecies and seven varieties, and K. grandiflora, which in the past was considered a variety of the later. However, the circumscription of the two species is problematic and they form the "K. coriacea complex". Kielmeyera coriacea is considered one of the main components of the Cerrado, while K. grandiflora is poorly known. Therefore, both specific taxa of the Coriaceae were investigated to clarify their relationship and to set out a more accurate classification, if necessary. Thus, we carried out morphological, anatomical, phenological, and molecular studies with the two species of the complex. Morphological and leaf anatomy studies were not satisfactory informative and revealed inconsistent differences between the species. Only the secondary veins pattern, the leaf shade and quantity and distribution of phenolic compounds in leaves tissues could be considered diagnostic characters. In addition, the analysis of the leaf surface in Scanning Electron Microscope showed a distinct pattern of epicuticular structure in both species. Microsatellite markers were used in the molecular studies, due to their capacity to detect polymorphism at specific level. Twenty-two primers pairs were developed from an enriched library of K. coriacea and eleven of them amplified polymorphic and readable loci. In this species, the band pattern presented 12 to 32 bands per locus and two to eight bands per individual. Kielmeyera grandiflora showed a similar band pattern. For each species we sampled two populations (one allopatric and one sympatric, all from São Paulo state). Thirty plants of each population were genotyped with eight microsatellites and 213 alleles were found; almost half of that were shared by the two species. Different approaches using population genetics softwares indicated two distinct groups inside the four populations, supporting the maintenance of the two species proposed by Saddi. The presence of many alleles specific to K. grandiflora in K. coriacea plants of the sympatric area suggests an introgressive hybridization. Our results corroborated Saddis s proposal of recognize both K. grandiflora and K. coriacea, and the clarification of the infraspecific taxa of K. coriacea becomes imminent in the light of these new developed tools

ASSUNTO(S)

cerrados microsatellites (genetics) microssatelites (genetica) botany clusiaceae clusiaceae botanica - classificação savanas

ACESSO AO ARTIGO

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