Genetics and Molecular Biology
URI permanente para esta coleçãohttps://thoth.dti.ufv.br/handle/123456789/13110
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Item Genetic polymorphism among 14 elite Coffea arabica L. cultivars using RAPD markers associated with restriction digestion(Sociedade Brasileira de Genética, 2003) Sera, Tumoru; Ruas, Paulo Maurício; Ruas, Claudete de Fátima; Diniz, Leandro Eugênio Cardamone; Carvalho, Valdemar de Paula; Rampim, Leandro; Ruas, Eduardo Augusto; Silveira, Sheila Recepute daKnowledge of the genetic variability among genotypes is important for the transfer of useful genes and to maximize the use of available germplasm resources. This study was carried out to assess the genetic variability of 14 elite Coffea arabica cultivars using random amplified polymorphic DNA (RAPD) associated with a prior digestion of genomic DNA with restriction endonucleases. The accessions were obtained from the Coffea collection maintained at the Instituto Agronômico do Paraná (IAPAR), located in Londrina, Paraná, Brazil. Twenty-four informative RAPD primers, used in association with restriction enzymes, yielded 330 reproducible and scorable DNA bands, of which 224 (68%) were polymorphic. The amplified products were used to estimate the genetic variability using Dice’s similarity coefficient. The data matrix was converted to a dendrogram and a three-dimensional plot using principal coordinate analysis. The accessions studied were separated into clusters in a manner that was consistent with the known pedigree. The associations obtained in the dendrogram and in the principal coordinate analysis plot suggest the probable origin of the Kattimor cultivar. The RAPD technique associated with restriction digestion was proved to be a useful tool for genetic characterization of C. arabica genotypes making an important contribution to the application of molecular markers to coffee breeding.Item Genetic relationship in Coffea species and parentage determination of interspecific hybrids using ISSR (Inter- Simple Sequence Repeat) markers(Sociedade Brasileira de Genética, 2003) Ruas, Paulo M.; Ruas, Claudete F.; Rampim, Leandro; Carvalho, Valdemar P.; Ruas, Eduardo A.; Sera, TumoruInter-simple sequence repeat (ISSR) markers were used to evaluate genetic divergence among eight Coffea species and to identify the parentage of six interspecific hybrids. A total of 14 primers which contained different simple sequence repeats (SSR) were used as single primers or combined in pairs and tested for PCR amplifications. Two hundred and thirty highly reproducible fragments were amplified, which were then used to estimate the genetic similarity and to cluster the Coffea species and hybrids. High levels of interspecific genetic variation were revealed. The dinucleotide motif (GA)9T combined with other di- tri- and tetra-nucleotides produced a greater number of DNA fragments, mostly polymorphics, suggesting a high frequency of the poly GA microsatellite motifs in the Coffea genomes. The genetic similarity ranged from 0.25 between C. racemosa and C. liberica var. dewevrei to 0.86 between C. arabica var. arabica and Hybrid N. 2. The C. arabica species shared most of its markers with five of the six hybrids suggesting that it is the most likely candidate as one of the progenitors of those hybrids. These results revealed that ISSR markers could be efficiently used for genetic differentiation of the Coffea species and to identify the parentage of Coffea interspecific hybrids.Item Assessment of genetic variability within and among coffee progenies and cultivars using RAPD markers(Sociedade Brasileira de Genética, 2003) Silveira, Sheila Recepute; Ruas, Paulo Maurício; Ruas, Claudete de Fátima; Sera, Tumoru; Carvalho, Valdemar de Paula; Coelho, Alexandre Siqueira GuedesThe RAPD technique associated with restriction digestion of genomic DNA was used to assess the genetic variability within and among nine populations of Coffea arabica, including six progenies belonging to the Sarchimor germplasm, the progeny PR 77054-40-10 (Catuaí Vermelho IAC 81 x Icatu), and two commercial cultivars (IAPAR 59 and Catuaí Vermelho IAC-81). These populations were evaluated using analysis of molecular variance (AMOVA), genetic similarity among progenies, and percentage of polymorphic loci. A total of 99 RAPD markers were evaluated of which 67 (67.67%) were polymorphic. AMOVA showed that 38.5% and 61.5% of the genetic variation was distributed among and within populations, respectively. The fixation index (FST) of the genotypes was 0.385. The mean genetic variability estimated within populations ranged from 15.58 (IAPAR 59) to 8.27 (Catuaí Vermelho IAC 81). A distinct level of genetic variability was revealed for each of the coffee progenies and varieties studied. The methodology used in this investigation was useful to determine the genetic variability within and among C. arabica L. populations providing significant information for coffee breeding.