Análise dialélica para caracteres morfoagronômicos em pimenteiras ornamentais (Capsicumannum L.)

• Ano de defesa: 2014
• Autor(a) principal: Fortunato, Flávia Laís Gomes
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal da Paraíba; Brasil; Ciências Fitotecnia e Ciências Ambientais; Mestrado Profissional em Artes em Rede Nacional (PROFARTES); UFPB
• Palavras-chave em Português: Pimenteiras ornamentais; Capsicumannum L.; Analise dialélica I.; CNPQ::CIENCIAS AGRARIAS::RECURSOS FLORESTAIS E ENGENHARIA FLORESTAL
• Link de acesso: https://repositorio.ufpb.br/jspui/handle/123456789/27446

The Capsicum genus comprises a large variety of hot and sweet peppers, with different sizes, colors and flavors. The realization of morphological and agronomic studies is essential for characterizing existing types and varieties. In this sense, the present work aims to characterize and evaluate the genetic divergence among eight accessions of pepper (Capsicum annuum). Specifies estimate the general combining ability (GCA), the combining ability (SCA) and heritability using 11 quantitative traits, and determine the most promising crosses for ornamental purposes, among six parents of pepper (Capsicum annuum). To analyze the variability eight genotypes based on twenty one quantitative traits were evaluated. Data were subjected to analysis of variance by F test at 5 % and 1 % significance level, the means were grouped by the Scott Knott test at 5 % and 1 % significance level. For the analysis of genetic divergence we used the method of grouping Tocher and canonical variables. The relative importance of features for the divergence was calculated based on the proposed by Singh (1981) and Canonical variable analysis method. The treatment effects were significant, the F test at the 1% level for all traits, except for the crown width and stem diameter, which were significant at 5 % probability. According to the methodology Tocher, based on the Mahalanobis distance, the accessions were collected into two groups. In the first group are the accesses 348, 349, 352, 347, 346 and 356, the second group was formed by the accesses 355 and 357. In the analysis of canonical variables, the first three variables explained 94.18 % of total variance, being formed four distinct groups according to the graphic dispersio. According to the canonical variate feature fresh matter was the one with the highest value in eigenvector eigenvalue last and may be discarded in future studies. By the method of Singh (1981), it was determined that three characteristics contributed 68.43 % of genetic divergence, while the others contributed only 31.57%. The eight accesses Capsicum annuum were analyzed divergent, showing genetic variability, thereby revealing the potential of them to be used as parents in breeding of ornamental pepper programs. To determine the general and specific combining ability in diallel analysis was performed according to the method of Griffing (1956) method II, fixed model. Significant differences between the effects of GCA CGA and were evaluated using the t-test values. The effects of GCA and SCA were significant, the F test at the 1% level for all almost all caractereres assessed with the exception of stem length, diameter and length of the corolla of petals, suggesting that additive genetic effects and non-additive are involved in the genetic control of these traits. The non-additive gene effects, epistasis and / or dominance, were more important than additive effects in controlling plant height, crown width, leaf length, petiole length, leaf width, length and anther length fillet. Stem diameter showed how much non-additive additive effects. To stem length, diameter and length of the corolla of petals, additive effects were more important. The parents 346, 348 and 349 may be indicated for use as parents in breeding of ornamental pepper programs, based on their values of GCA. The best combinations hybridwere 348 x 356, 348 x 355, 347 x 355 and 349 x 356 for the sheet length, petiole length and leaf width and 346 x 347 and 346 x 348 for corolla length and diameter of the petal. To study the inheritance data were subjected to diallel analysis according to the methodology of Hayman (1954). The test of the adequacy of the additive - dominant model, we used the t statistic. All statistical analyzes xi were performed using the computer program Genes (Cruz, 2006). The effects of treatment (parents and F1 hybrids) were significant, the F test at the 1% level for all traits. As to the sufficiency of additive - dominant model test, all features were appropriate. The recessive alleles were responsible for the increase in stem diameter, petiole length and diameter of the petals. For plant height, crown width, stem length, leaf length, leaf width, corolla length, anther length and length of the fillet increased character was provided by the dominant allele concentration. The components of genetic variance (D , F , H1 , H2 , h2 and H1 - D) and environmental (E) showed no significant values for almost all traits , except plant height showed that the mean value of h2 . The Broad sense heritability was high for all traits, indicating that most of the phenotypic variation observed in nature is genetic in nature and may be transmitted to their offspring. For most traits the narrow sense heritability values were satisfactory, except for the crown width, leaf length and petiole length, indicating the selection to improve these characteristics.