Avaliação de famílias S3 de milho-pipoca via topcrosses

• Ano de defesa: 2013
• Autor(a) principal: Miotto, Acácio Antonio
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Estadual de Maringá; Brasil; Departamento de Agronomia; Programa de Pós-Graduação em Agronomia; UEM; Maringá, PR; Centro de Ciências Agrárias
• Palavras-chave em Português: Milho-pipoca; (Zea mays L; var; everta); Capacidade de expansão; Dialelo parcial; Rendimento de grão; Brasil.; Popcorn; Everta); Expandability; Partial diallel; Grain yield; Brazil.; Ciências Agrárias; Zootecnia
• Link de acesso: http://repositorio.uem.br:8080/jspui/handle/1/1667

The use of topcrosses is one of the most used alternative for partially inbreed families selection during inbred lines synthesis which precedes commercial corn hybridization. This study aimed to evaluate the discrimination efficiency of 38 S3 families obtained from hybrid IAC-125 by three testers (inbred line P3.3; open-pollinated variety Angela and three-way hybrid Jade). The topcrosses evaluation occurred in the season 2012/2013, in Maringa and Sabáudia, located in northern of Paraná state, using three experiments at each location, one experiment for each topcrosses group related to each tester. The experiments were installed side by side in a randomized blocks design with three replications. The main traits evaluated were: grain yield and popping expansion. The general and specific combining ability were obtained using Griffing?s model (1956), adapted by Geraldi and Miranda Filho (1988). The ability of testers to discriminate the S3 families was measured by a differentiation index (D) developed by Fasoulas (1983). The highest estimate of genotypic variance for grain yield was viewed by hybrids obtained from the crossing with Jade tester in both locations. The highest genotypic variance for popping expansion in Maringa was revealed by Angela in first and Jade in second. In Sabáudia, Jade was again the tester that showed the highest estimate of genotypic variance. Jade was also the tester that showed the most efficiency discrimination between families according to Fasoulas methodology. Therefore it can be concluded that because of the practicality of the adoption of a single tester, makes Jade a good alternative for topcrossing programs due It satisfactory performance as a tester for characters of greater relevance in popcorn breeding programs.