Teses e Dissertações
URI permanente desta comunidadehttps://thoth.dti.ufv.br/handle/123456789/2
Navegar
1 resultados
Resultados da Pesquisa
Item Estimation of genetic parameters and SNPs based molecular diversity of Coffea canephora(Universidade Federal de Viçosa, 2015-08-13) Bikila, Bayisa Asefa; Sakiyama, Ney SussumuThe objective of this work was to assess the genetic parameters in Coffea canephora (Robusta and Conilon groups) and to analyze the genetic diversity of C. canephora accessions, which were genotyped with SNPs molecular markers. The phenotypic data were analyzed using the mixed model methodology (REML/BLUP) through the Selegen software for estimation of genetic parameters. The results showed a low genetic variability (CVg%) among the clones of Robusta and Conilon for all the evaluated traits. On the other hand, relatively high residual coefficients of variation (CV%) for most of the traits were recorded implying that these traits seem to be highly influenced by the environmental variation. The estimated repeatability for most of the traits was lowest indicating the irregularity of the superiority of the individuals among the measurements for these characters in the case of both clones showing high irregularity of the performance across measurement, which demonstrate that genotype selection based on those traits is not reliable strategy. Generally, for both groups of clones, there was low interaction with year, as observed by the genotypic correlation across measurement (r gmed ) for most of the characters evaluated demonstrating that selection can be performed at any of the development stages used for measurement. Genetic diversity was investigated using 46074 polymorphic SNP markers covering the entire genome of 50 C. canephora clones (24 Conilon and 26 Robusta). The genetic similarity between each pair of clones was calculated by the Jaccard coefficient and information about diversity among clones was inferred by means of the dendrogram built using UPGMA method (Unweighted Pair-Group Method with Arithmetic Mean) with the program NTSYS pc2.1. Hence, the dendrogram divided the clones into six groups. Generally, the analysis showed that the C. canephora genotypes were clearly divided into diversity groups that can be used for breeding programs.