White mold, caused by Sclerotinea sclerotiorum (Lib.) de Bary is one of the most important diseases of the common bean (Phaseolus vulgaris L.) worldwide. Physiological resistance and traits related to disease avoidance such as architecture contribute to field resistance. The aim of this study was to verify the efficiency of recurrent selection in physiological resistance to white mold, "Carioca" grain type and upright habit in common bean. Thirteen common bean lines with partial resistance to white mold were intercrossed by means of a circulant diallel table, and seven recurrent selection cycles were obtained. Of these cycles, progenies of the S 0:1 , S 0:2 and S 0:3 generations of cycles III, IV, V and VI were evaluated. The best (8 to 10) progenies of the seven cycles were also evaluated, in two experiments, one in the greenhouse and one in the field. Lattice and/or randomized block experimental designs were used. The traits evaluated were: resistance to white mold by the straw test method, growth habit and grain type. The most resistant progenies were selected based on the average score of resistance to white mold. Subsequently, they were evaluated with regard to grain type and growth habit. Recurrent selection allowed for genetic progress of about 11 % per year for white mold resistance and about 15 % per year for the plant architecture.There was no gain among cycles for grain type. Progeny selection and recurrent selection were efficient for obtaining progenies with a high level of resistance to white mold with "Carioca" grain type and upright habit.

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RESUMOObjetivou-se neste trabalho, selecionar famílias de feijoeiro promissoras para a produtividade de grãos com tipo de grãos ideal utilizando informações fenotípicas e de marcadores moleculares ligados a QTLs. Foram utilizadas 100 famílias F 3:7 , avaliadas em três safras, com dois experimentos/safra, totalizando seis experimentos. A primeira safra foi a da seca/2007, na qual conduziu-se um experimento em Lavras-MG e o outro em Ijaci-MG. Nas safras de inverno/2007 e águas 2007/2008, foram conduzidos, em cada uma, um experimento em Lavras-MG e outro em Lambari-MG. Em todos eles foi utilizado o delineamento látice triplo 10x10, com parcelas de duas linhas de dois metros. As famílias foram avaliadas pela sua produtividade de grãos. Em apenas um dos experimentos de cada safra foi avaliado o tipo de grão. Os dados foram submetidos à análise de variância individual e conjunta, por local e por safra. 480 marcadores microssatélites foram testados para identificar polimorfismo entre os genitores. Os oito marcadores polimórficos identificados foram utilizados para a genotipagem das famílias. Entre esses, cinco explicaram parte da variação da produtividade de grãos. Os marcadores explicaram pequena porcentagem da variação fenotípica e apresentaram alta interação QTLs x ambientes. O ganho com a seleção fenotípica para produtividade de grãos foi de 7,4%, e de 9,6% para tipo de grãos, adotando a intensidade de seleção de 5%. A seleção assistida por marcadores foi equivalente à fenotípica para produtividade de grãos, porque apenas um marcador mais estável contribuiu para a seleção com base na média dos ambientes. Termos para indexação:Phaseolus vulgaris, linhagens,seleção assistida por marcadores, seleção fenotípica, microssatélites. ABSTRACTThe objectives of this research were to select com mon bean families with high grain yield and ideal grain type using phenotypical information and molecular markers linked to the QTLs. One hundred F 3:7 families were evaluated in three seasons, in two field experiments per season. Two experiments were set up in the counties of Lavras and Ijaci in the dry season/2007, other four experiments were set up in Lavras and Lambari, two in the winter season/2007 and two in the 2007/2008 rainy season. A 10x10 lattice design was used in all experiments, using 2m-long plots and rows 50cm apart. The families were evaluated based on grain yield in all experiments, and based on grain type in one experiment per season. Moreover, 480 microsatellite markers were tested in the parents. Eight markers were polymorphic and used for genotyping the families. Among them five explained part of the grain yield variability and presented high interaction by environments. Selecting 5% of the families the genetic gain was of 7,4% for grain yield and 9,6% for grain type. The marker-assisted selection gave a similar result to the phenotypic selection because only one more stable marker of the along with average grain yield was used in the selection.

The most efficient breeding strategies in crop improvement is the selection based on heritability and combing ability estimates for the traits of economic importance or commercial value. Therefore, the present study was to obtain estimates of heritability and to estimate the phenotypic and genotypic correlations among the characteristics of interest. The commercial cultivars ‘Aromas’, ‘Camarosa’, ‘Dover’, ‘Festival Flórida’, ‘Oso Grande’, ‘Sweet Charlie’ and ‘Milsei-Tudla’, and 103 F1 hybrids from the crossbreeding experiments were evaluated for four traits of commercial fruit yield and 13 traits of fruit physical and chemical quality. The estimated genetic parameters were general combining ability, specific combining ability, genotypic correlation among traits, estimates of heritability, genetic and phenotypic variance. The ‘Camarosa’ and ‘Aromas’ cultivars were the most promising cultivars for use as parents in the commercial fruit production, while ‘Dover’ and ‘Sweet Charlie’ cultivars were selected for taste of fruit in strawberry breeding, as they showed higher concentrations of favorable alleles in the F1 hybrid population. It was also verified some strong genetic correlations for some pairs of characteristics in the present study that may allow indirect selection. The estimation of these parameters is an important basis for decision making on the genetic engineering of strawberry.

The aim of this study was to use multiple DNA markers for detection of QTLs related to resistance to white mold in an F2 population of common bean evaluated by the straw test method. The DNA from 186 F2 plants and from the parents was extracted for genotypic evaluation using SSR, AFLP, and SRAP markers. For phenotypic analysis, 186 F2:4 progenies and ten lines were evaluated, in a 14 × 14 triple lattice experimental design. The adjusted mean values of the F2:4 progenies were used for identification of QTLs by Bayesian shrinkage analysis. Significant differences were observed among the progenies for reaction to white mold. In identification of QTLs, 17 markers identified QTLs for resistance—13 SSRs and 4 AFLPs. The moving away method under the Bayesian approach proved to be efficient in the identification of QTLs when a genetic map is not used due to the low density of markers. The ME1 and BM211 markers are near the QTLs, with the effect of increasing resistance to white mold, and they have high heritability. They are thus promising for marker-assisted selection.