Análise dialélica e pungência dos frutos em Capsicum chinense

• Ano de defesa: 2007
• Autor(a) principal: Pereira, Giselda Maria
• Orientador(a): Finger, Fernando Luiz
• Banca de defesa: Barbosa, José Geraldo , Pinto, Cleide Maria Ferreira
• Tipo de documento: Tese
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Viçosa
• Programa de Pós-Graduação: Doutorado em Genética e Melhoramento
• Departamento: Genética animal; Genética molecular e de microrganismos; Genética quantitativa; Genética vegetal; Me
• País: BR
• Palavras-chave em Português: Capsicum; Pungência; Dialelo
• Palavras-chave em Inglês: Capsicum; Pungency; Dialel
• Área do conhecimento CNPq: CNPQ::CIENCIAS AGRARIAS::AGRONOMIA::FITOTECNIA::MELHORAMENTO VEGETAL
• Link de acesso: http://locus.ufv.br/handle/123456789/1423

The production of peppers in Brasil has been increased substantially in the past years, being the southern and central-western the main producers. The breeding of Capsicum species aims mainly to obtain fruits with quality, high yield genotypes and plants resistant to the major diseases affecting the crop. Among the fruits characteristics, the pungency is one of the main importance for the consumers. The goals of this work were to identify accesses with high potential to be used in breeding programs, with the objective to improve quality using the estimative of genetic parameters. As well as to study the accumulation of capsaicinoids during maturation of the fruits and evaluate the action of peroxidases in capsaicinoid metabolism. For this 11 accessions of Capsicum chinense, being six hot and five sweet. In order to obtain the genetic parameters it applied a partial dialel, crossing the pungent fruit chili parents with the no pungent, where were analyzed 11 characteristics. For the analysis of capsaicinoid metabolism and activity of peroxidases it was evaluated fruits of 11 accessions at mature-green, 50% ripe and full ripe stages. Analysis of the dialel data showed the importance of the additive genetic effects in all evaluated characters in at least one group of parents. In addition to the importance of the non additive genetics affects evaluated in this work. For the characteristics related to yield, the combinations that had higher potential to generate superior genotypes were BGH 4289 (44) x BGH 4223 (39), BGH 5012 (72) x BGH 1716 (16), BGH 1716 (17) x BGH 6233 (85) and BGH 4289 (44) x BGH 6233 (85). In order to obtain fruits with higher yield for production of sauces and paprika, and elevated content of vitamin C, the crosses more appropriated were BGH 5012 (72) x BGH 6378 (98) and BGH 4289 (44) x BGH 1716 (16), respectively. The combinations BGH 4289 (44) x BGH 6378 (98), BGH 4733 (54) x BGH 1716 (16) and BGH 5012 (72) x BGH 6233 (85) can contribute for the increment of the two major capsaicinoids content. The analysis of casaicinoid accumulation showed that casaicin in accumulated in larger amount compared to dihydrocapsaicin. The majority of the pungent accessions had decrease in the capsaicin and dihydrocapsaicin contents during ripening. The activity of peroxidases increased with the beginning of ripening for most of the sweet or hot fruit accessions. The increase in peroxidases activity and decrease in the capsaicinoid concentration showed that the action of the enzyme affected the metabolism of capsaicin and analog compounds. The results of this work confirm the genetic variability for the accessions evaluated and justify the use of these accessions in crosses for production of superior genotypes. Besides, the present study reinforces the importance of peroxidases in the oxidation of capsaicinoids.