Aspectos da demografia do cajueiro-do-campo (Anacardium humile) em áreas de Cerrado do Estado de São Paulo e construção de bibliotecas enriquecidas de microssatélites para a espécie / Demographyc aspects of cajueiro-do-campo (Anacardium humile A St. Hill) in cerrado areas at the State of São Paulo and the construction of the genomic enriched library of microsatellites

AUTOR(ES)
DATA DE PUBLICAÇÃO

2009

RESUMO

Brazilian cerrado is one of the richest and plants endemism biomes, but with a high deforestation in the last decades, resulted in habitats fragmentation and extinction threat of hundreds of plant species. Among these threatened species is Anacardium humile, known as cajuzinho-do-campo, a camephyth plant with a wide distribution through the country, which serves as aliment to man and some animals and presents some medical properties. Studies about Anacardium humiles populations structure are very scarce in the literature, and its understanding is fundamental to the preservation and conservation of the species. Thus, the present work had two objectives: 1) in two distincts cerrado plant physiognomies, estimate the abundance of species ramets, its spatial distribution pattern in macro and microscale, and the influence of canopy openness percentage in the determination of this pattern; 2) construction of a genomic enriched library with microsatellites to the species and primers design from this library, to isolate loci with potential to be used as genetic markers. In relation to the first objective, three 0,5 ha quadrats, divided in 200 contiguous quadrats of 25 m2, were installed (two in a typical cerrado to cerradão fragment and one in an open cerrado fragment), and all species ramets were sampled by count, being differentiated in with and without Contarinia sp attack ((Diptera: Cecidomyiidae). Photographies of the center of each parcel were taken to determinate the percentage of canopys openness. The abundance of ramets were higher in the most opened areas, but the incidence of Contarinia sp attack were higher in the closest fragment. Macroscale (Dispersion Index) and microscale analysis (Spatial Autocorrelation) showed that species ramets present an aggregated pattern in both areas, but this aggregation is not related to the percentage of canopys openness, although there are significant differences to this last factor among the grids, indicating that pattern is due to its way of life. In relation to the second objective, the construction of genomic library enriched with microsatellites resulted in 180 clones, which 84 were sequenced, being detected 23 sequences containing microsatellites, representing a librarys enrichment of 27,38%. 15 primers pairs were designed among the 34 obtained microsatellites, but only 7 pairs amplified. From these, five pairs were visualized in acrylamide, and one polymorphic loco was observed. The number of obtained clones is in accordance with the observed in studies with another species from Anacardiaceae family, showing protocols efficiency. Problems with the optimization of reagents may have impeded the amplification of some primers, once that procedures to their design were suitable. Polymorphism results are preliminaries, due to low number of evaluated individuals. At least one loco presents potential as genetic marker.

ASSUNTO(S)

marcador molecular. cerrado caju - distribuição cashew distribuction cerrado molecular marker.

ACESSO AO ARTIGO

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