Grupos heteróticos e seleção recorrente recíproca em cana-de-açúcar

• Autor(a) principal: Paula, Thiago Otávio Mendes de
• Data de Publicação: 2013
• Tipo de documento: Tese
• Idioma: por
• Título da fonte: LOCUS Repositório Institucional da UFV
• Texto Completo: http://locus.ufv.br/handle/123456789/1385
• topic: Saccharum spp.; Fatorial; Capacidade de combinação; Delineamento genético; BLUP; Saccharum spp.; Factorial; Combining ability; Genetic lineation; BLUP; CNPQ::CIENCIAS BIOLOGICAS::GENETICA

The Sugarcane Breeding Program from Federal University of Viçosa has been routinely done experiments to evaluate the potential of sugarcane families. The aim are select the best crosses and predict the clones merit as parents. Recently, the crossings have been conducted in a scheme called disconnected factorial, because among other advantages, it allows the estimation of specific combining ability (SCA). The SCA estimates can be used as indicators of heterosis (genetic diversity and allelic dominance) to define heterotic groups and then used them in the Reciprocal Recurrent Selection (SSR). Therefore, It was evaluated 80 families of sugarcane obtained from crosses between 38 clones by diconected factorial, with the purpose to estimating genetic parameters, select crosses and parents, and identify heterotic groups. The genetic-statistical analysis was performed by REML/BLUP. The results showed predominance of non-additive effects to explain the genetic variation for tons of stalks per hectare (TSH), tons pol per hectare (TPH) and tons of fiber per hectare (TFH). The additive effect was predominant for brix, fiber and sugar in the cane juice (PCC). Estimates of SCA allowed two heterotic groups that may be used in reciprocal recurrent selection. The prediction of the breeding values of parents by disconnected factorial, is an alternative that should be used in sugarcane breeding programs.