Genética da resistência à requeima e seleção de famílias superiores derivadas do cruzamento Solanum lycopersicum SANTA CLARA e Solanum habrochaites f. glabratum BGH 6902

• Autor(a) principal: Gomes, Carlos Nick
• Data de Publicação: 2011
• Tipo de documento: Tese
• Idioma: por
• Título da fonte: LOCUS Repositório Institucional da UFV
• Texto Completo: http://locus.ufv.br/handle/123456789/1172
• topic: Solanum lycopersicum; Solanum habrochaites f. glabratum; Solanum lycopersicum; Solanum habrochaites f. glabratum; CNPQ::CIENCIAS AGRARIAS::AGRONOMIA::FITOTECNIA::MELHORAMENTO VEGETAL

The late blight is the most destructive of disease affecting the tomato, with losses in excess of three billion dollars annually worldwide. Wild germplasm are often used in tomato breeding programs. However, the progeny of these crosses often have undesirable agronomic characters, especially on the quality of fruit. There are no resistant cultivars on the market, and success to obtain requires study of the mechanisms associated with inheritance, gene effects and allelic and non allelic interactions that operate in the expression of resistance, geneticestatistics parameter estimation and quantification of the association between resistance and quality characters fruit, as well as the use of efficient selection criteria to select superior families. We studied the inheritance and to estimate genetic parameters associated with to P. infestans in four segregating generations (F2, F2:3, RC1:1 e RC1:2) in addition to the parents and F1, in the field conditions; geneticstatistic parameters was estimated, assessed the association between resistance and quality characters of fruits and compared different criteria for selection in progenies of crossing Solanum lycopersicum and Solanum habrochaites f. glabratum as the area under curve of progress of late blight and fruit quality attributes, total soluble solids and total titrable acidity in 220 F2:3. Constacted that the genetic control of resistance to late blight is quantitative, with recessive alleles acting on trait expression. The dominance exerts substantial influence on trait expression. Resistance to late blight is greatly influenced by the environment, in view of the magnitude of the environment component of variance in the F2:3 and a low magnitude estimate of broad sense heritability. The additive-dominant model was sufficient to explain variations in characteristic. Heritability, obtained by parent-offspring regression, was high and indicated the possibility of satisfactory earnings and success in the introgression of resistance alleles. The correlations were negative, the high-magnitude intermediate between the variables, the area under the curve of progress of late blight, soluble solids and titrable acidity and indicated that resistance alleles may be associated with alleles that contribute positively to the satisfactory and appropriate to the ideotype proposed decrease in area under the curve of progress of late blight, followed by an increase in the amounts of soluble solids and total titrable acidity. The direct and indirect selection and index Mulamba Mock and resulted in more balanced individual gains and higher total grains.