Seleção genômica ampla no melhoramento vegetal

• Autor(a) principal: Resende Júnior, Márcio Fernando Ribeiro de
• Data de Publicação: 2010
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: LOCUS Repositório Institucional da UFV
• Texto Completo: http://locus.ufv.br/handle/123456789/4727
• topic: Seleção genômica; Seleção assistida por marcadores; DArTs; Eucalyptus; Genome selection; Markers-assisted selection; DArTs; Eucalyptus; CNPQ::CIENCIAS BIOLOGICAS::GENETICA::GENETICA QUANTITATIVA

The Genome Wide selection was proposed in 2001 to predict the phenotype values based in molecular markers information. In a previus step, the effect of each of each marker in controlling the genetic variance is estimated. This technology has already been used in animals, however, no report of its use was made for plants. This work aimed to study the impact of GWS, first in a simulated dataset, then in two Eucalyptus populations. Besides that, on the simulated data, it was compared the efficiency of using dominant markers versus the use of codominant ones. The simulation generated one population controlled by many genes (polygenic) and one population with olligogenic control. There were different situations of linkage disequilibrium among the marker and the QTL, different number of markers controlling the trait and heritabilities of 20, 30 and 40%. It was evaluated the prediction ability and the accuracy of the GWS. The results of accuracy were high, which turn in to a selection gain of up to 500% in the selection dataset and the use dominant markers at higher densities is more efficient than the use of dominant markers with lower densities. The Euvalyptus populations were genotyped for total height, diameter at breast height (DBH) and Pilodyn. The values of accuracy were 0,67 for height and 0,69 for DBH in the first population and ,53, 0,62, and 0,53 for total height, DBH and Pilodyn respectively. Those result turn in to a selection gain that varied from 430% to 723% with a reduction of 7 years in the breeding cycle. This showed significant results and gave evidences that the use of GWS in plants is possible to improve the way plant breeding is actually performed.