CONTROLE GENÉTICO DO TEOR DE ÓLEO EM SEMENTES DE ALGODÃO (Gossypium spp)

• Ano de defesa: 2012
• Autor(a) principal: Faria, Gislâyne Maíra Pereira de
• Orientador(a): Cruz, Cosme Damião
• Banca de defesa: Oliveira, Marciane da Silva
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Viçosa
• Programa de Pós-Graduação: Mestrado em Genética e Melhoramento
• Departamento: Genética animal; Genética molecular e de microrganismos; Genética quantitativa; Genética vegetal; Me
• País: BR
• Palavras-chave em Português: Algodão; Análise de geração; Teor de óleo; Ganho de seleção
• Palavras-chave em Inglês: Cotton; Generation analysis; Oil content; Gain of selection
• Área do conhecimento CNPq: CNPQ::CIENCIAS AGRARIAS::RECURSOS FLORESTAIS E ENGENHARIA FLORESTAL::SILVICULTURA::GENETICA E MELHORAMENTO FLORESTAL
• Link de acesso: http://locus.ufv.br/handle/123456789/4775

The goals of genetic improvement of cotton have always been targeted for improvement in production and fiber quality. Currently, there is need to identify alternatives to the use of oil as fuel for diesel engines. The cottonseed oil has many nutritional advantages over other oils and can be found on the market numerous products. The constant search for genotypes with high oil content, without however losing the high productivity has been already achieved the goal of many researchers in recent years of cotton. One of the objectives of this study was to analyze the genetic inheritance of oil content in cotton. To do this, I evaluated the populations resulting from crosses CNPAC300/91 (P1) and V3 (P2), autofecundados originated from the backcrosses CNPAC300/91 (P1) e F1; V3 (P2) e F1, the parental lines. We used the full and reduced models, to explain the behavior of the average generation, character study, and estimation of variance components. The oil content behaved as a quantitative character. Parents CNPAC 300/91 x V3 were not as contrasting to the oil content, this fact committed biometric interpretations, since little genetic variability was expressed. The variance attributed to dominance deviation, accounted for most of the genetic variance at the crossroads, CNPAC 300/91 x V3. The gene effect attributed to the shift of dominance had the highest estimate and the largest variance, therefore, presented itself as a major gene effect. The additive model-dominate was satisfactory to explain the average behavior of generations, the trait studied. The methodology of generations proved invaluable for the study of the main genetic parameters of cotton crops. The other goal was to select genotypes segregating cotton in the F5 generation by estimating genetic and phenotypic parameters such as heritability, gains from the direct and indirect selection. To this end, the germplasm bank of Embrapa Cotton with 300 hits, three hits were selected with high oil content, which are BRS Aroeira with 25,31%, 26,71% in Acala 1.13-3-1 FURRS and 149 with 1,26% , which were crossed with elite lines from the Breeding Program of Embrapa Cotton, making a total of nine types of crosses. The analyzes were determined from the F3 seeds, which were conducted until the F5 generation with 22 lines, are evaluated along with two witnesses, the lineage CNPAC 300/91 and access V3 that have the lowest and the highest oil content, respectively, in the evaluation by Carvalho et al. (2010). The 22 lines were evaluated in a completely randomized trial with four replications, in each replicate were made three analyzes of the oil content, and for the analysis of variance was used the average of these three assessments. The estimated data of the oil content of the generations of studies allowed to estimate the phenotypic variance, genotypic, environmental, heritability by parent-child regression, and F3 (father) and F5 (son), and obtaining genetic gain. It was determined that there is genetic variation among offspring, so the possibility of obtaining gains by selection among and within progenies. The F5 generation is best to maximize the genetic gain from selection for seed oil content in cotton. The genetic gain estimated in the F5 generation corresponded to 4.98%, higher than the F3 generation indicating that selection for the character will be much more efficient to perform the direct selection in F5. The line CNPA 2011/12 has the potential to be used as parent in breeding programs aimed at improving the oil content of cotton.