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The aim was to estimate the minimum number of plants required per plot to assess the anthracnose severity by artificial inoculation of V2 stage plants. Seventy-eight carioca common bean cultivars were inoculated in 13 experiments to assess its reaction to races 65, 73, 81, and 89 of Colletotrichum lindemuthianum. Sample sizes ranged from one to nine plants were adopted to setting the number of plants per plot. A total of 1000 samplings were performed for each sample size. The following parameters were estimated in each sampling: accuracy, coefficient of variation and Pearson's correlation. The mean values of each parameter in the 1000 samplings for each sample size were subjected to quadratic regression with a plateau as a function of sample size for each experiment. Six plants per plot were needed to assess the severity of anthracnose by artificially inoculating the pathogen on common bean plants at the V2 stage. [ABSTRACT FROM AUTHOR]

The aims of this study were to estimate genetic parameters, predict genotypic values, and analyze the genotypic divergence in S0 and S1 peach trees evaluated in a subtropical environment by the mixed model methodology. For this, twenty-two clones were evaluated for plant and fruit traits. Genotypic variance among clones was significant. The individual broad-sense heritabilities ranged from 0.11 to 0.84, and the individual repeatability coefficients ranged from 0.15 to 0.89. The genotypic coefficients of variation were higher than 10% for most of the traits. Clustering based on plant and fruit traits led to the formation of two and five mutually exclusive groups, respectively. Multivariate analysis of principal components indicated that some traits could be excluded from genetic evaluation. Considering the yield trait and the selection of five clones, predicted gain from selection was 70%, which shows the possibility of considerable genetic progress from clonal selection in peach trees. [ABSTRACT FROM AUTHOR]

Carioca grains are the most cultivated commercial group of common bean and Fusarium oxysporum f. sp. phaseoli (Fop) is an important disease under field conditions. Genetic resistance is the most effective control strategy. Thus, our objective was to study the inheritance of Fop resistance in the carioca grain type common bean. Lines CNFC 11965 (S) and CVIII 8511 (R) were crossed to obtain F1 and F2 generations and backcrosses, inoculated with the isolate FOP UFV 01, and severity grades used to estimate genetic parameters. Segregation of resistant and susceptible plants in the F2 generations and backcrosses resulted in dominant monogenic inheritance of Fop resistance. The high values of heritability emphasized the probability of success in the selection processes because environmental factors were not significant. The carioca grain line CVIII 8511 is promising, and its Fop resistance gene can be transferred to commercial cultivars of this group using the backcross method. [ABSTRACT FROM AUTHOR]

Aiming to incorporate resistance to the anthracnose and angular leaf spot pathogens in the common bean lines BRSMG Talismã, VC8 and VC9, crosses were made between these lines and the line Rudá-R, donor of the alleles Phg1, Co-4, Co-10, which confer resistance to Pseudocercospora griseola and Colletotrichum lindemuthianum. After the crosses, the backcross populations were obtained, and the RC1F1 plants were inoculated with race 65 of C. lindemuthianum. The resistant plants were genotyped with the markers SCARH13, SCARY20 and SCARF10, linked to the alleles Phg1, Co-4 and Co-10, respectively. Based on the molecular data, 44 plants were selected. The progenies originating from multiplication of these plants were evaluated over three seasons for grain yield, plant architecture and grain aspects. Based on these considerations and molecular data, 13 promising progenies were selected for developing inbreds [ABSTRACT FROM AUTHOR]

Late blight caused by the oomycete Phytophthora infestans is a destructive tomato disease in Brazil and in other tropical and subtropical regions. The purpose of the present study was to analyze the inheritance of resistance to late blight and determine the genetic factors that contribute to the resistance in the inbred line "163A". The Line "163A" resulted from an interspecific cross between Solanum lycopersicum and S. habrochaites f. glabratum, achieved by researchers at Universidade Federal de Viçosa. Inoculated field with mixture isolates of pathogen with 1000 spores mL-1 and naturally infested field trials showed that the expression of "163A" against multiple isolates of the pathogen was stable. The genetic analysis supported the hypothesis of two recessive genes that controlls the resistance. The scaling test of additive-dominance model showed that it is a good fit for the data, which confirms the absence or neglect of epistasis [ABSTRACT FROM AUTHOR]

The objective of the present study was to assess the genetic potential of inbred carioca common bean families from five populations derived from crossings involving elite lines and a disease-resistant line (Rudá- R), and to assess the efficiency of SCAR molecular markers in selecting plants resistant to anthracnose and angular leaf spot, at the time of bulk formation. Plant architecture, yield and grain type were assessed. Significant effect among families within population was observed, suggesting wide genetic variability for the characters assessed. Twenty-six superior families were selected. The families contained the greatest number of markers, identified by SCAR molecular markers in the F4 generation. Eighteen of these families were resistant to the races 65 and 453 of Colletotrichum lindemuthianum and five were resistant to the race 63.23 of Pseudocercospora griseola. Thus selection assisted by SCAR markers, in the F4 generation, was an important tool in common bean breeding. [ABSTRACT FROM AUTHOR]

The purpose of this study was to characterize the genetic variability in 100 genotypes of the Active Germplasm Bank of common bean of the Federal University of Viçosa, by morphological descriptors, classify them in groups of genetic similarity and to identify the degree of relevance of descriptors of genetic divergence. The genotypes were evaluated based on 22 quantitative and qualitative morphological descriptors. The highyielding genotypes V 7936, Gold Gate, LM 95103904, 1829 S 349 Venezuela, and PF 9029975, CNFC 9454 and Fe 732015, with upright growth, have potential for use as parents in common bean breeding programs. By genetic divergence analysis, the genotypes were clustered in eight groups of genetic dissimilarity. By methods of principal components, 9 of the 22 descriptors were eliminated, for being redundant or little variable, suggesting that 10-20 morphological descriptors can be used in studies of characterization of genetic variation. [ABSTRACT FROM AUTHOR]

Studies highlight the hypocotyl diameter (HD) as an effective indicator of plant architecture (PA). Here, we estimated the genetic gain based on HD to improve PA. Twenty populations of cycles zero (C0) and one (C1), both in the F4 generation, were evaluated for PA, grain yield (GY) and HD. Plants with thickest HD in C0 were intercrossed in a circulant diallel mating design. In cycle C1, an estimated genetic gain of 4.93% was achieved for PA and 4.95% for HD. The populations with the highest probability of breeding lines with a thicker HD belong to cycle C1, and this selection strategy did not alter the GY of the populations of this cycle. Thus, indirect selection based on HD is promising for breeding for common bean PA by recurrent mass selection. [ABSTRACT FROM AUTHOR]

In breeding programs, understanding the potential of parents should be a way to spend significantly less time and costs to obtain new cultivars. For this, the objective of this study was to estimate the general and specific combining ability of parents aiming common bean breeding for resistance to Fusarium wilt (FW) based on disease severity and reduction in plant growth. Eight common bean genotypes were crossed in a 3 x 5 partial diallel mating scheme to obtain F1 hybrids. The parents and their 15 F1 hybrids were evaluated for severity of Fusarium wilt, area under the disease progress curve, percentage of plant height reduction and plant shoot fresh weight reduction and grain yield. The resistance of common bean to FW is controlled by a few dominant genes. The reduction in plant growth is controlled by a different set of genes that can increase the selection efficiency of parents for common bean breeding. [ABSTRACT FROM AUTHOR]

The objective of this study was to estimate the genetic gain of two recurrent selection cycles in common bean breeding and identify families with the potential to generate superior lines. The base population, cycle zero (C0), was obtained by combining 20 carioca bean parents, populations with favorable phenotypes for several agronomically important traits. The parents were recombined in a circulant diallel scheme, in which each parent participated in two crosses, generating 20 populations. From these populations, families were derived and evaluated for three seasons in the generations F2:3, F2:4 and F2:5. The same procedures of recombination and evaluation in C0 were performed in cycle one (CI). The genetic gain for yield, estimated from the simultaneous evaluation of the 40 best families of each cycle, was 8.6%. Families with potential to generate superior lines to cultivar Pérola were identified, especially among the CI families. [ABSTRACT FROM AUTHOR]

The common bean cultivar "BRSMG Realce", recommended for the state of Minas Gerais, has high yield potential and resistance to powdery mildew, bacterial wilt and to anthracnose pathotypes 65, 73, 77, 81, 91, 475 and 479. The plants and pods are high, resulting in lower loss during mechanical harvest. [ABSTRACT FROM AUTHOR]

This study was carried out for the purpose of estimating genetic progress after two cycles of recurrent selection in red bean breeding and of obtaining new lines. In cycle zero, F3:5 and F3:6 families were evaluated. In cycle one, the families were extracted in generation F5 and evaluated in generations F5:6 and F5:7. As the families were evaluated in different years and generations, the estimate of genetic progress was obtained by simultaneously evaluating the 30 best lines obtained at the end of each cycle in experiments conducted through three crop seasons. After two cycles of recurrent selection, genetic progress, in the mean value of the crop seasons, was 7.5% for grain yield, 7% for grain appearance, 33.4% for resistance to rust and 13.2% for resistance to angular leaf spot. Lines of red beans were obtained with potential for being included in future Value for Cultivation and Use (VCU) testing for Minas Gerais, Brazil. [ABSTRACT FROM AUTHOR]

The cultivar BRSMG Madrepérola, recommended for cultivation in Minas Gerais, has the feature of maintaining a light grain color for a longer period than other Carioca grain cultivars. The yield potential is high and the resistance level good to the major anthracnose races in the region. [ABSTRACT FROM AUTHOR]

The bean cultivar BRSMG União as a new option of a bean cultivar with jalo grains for the state of Minas Gerais. The cultivar BRSMG União had an average grain yield of 9.8% above the mean of the controls (Jalo EEP 558 and BRS Radiante) and was resistant to powdery-mildew. [ABSTRACT FROM AUTHOR]

The purpose of this study was to evaluate the performance potential of red bean lines, derived from populations of the first cycle of recurrent selection in the common bean breeding program of the Federal University of Viçosa, Minas Gerais. In the F3:5, F3:6 and F3:7 generations, 243 families from 18 segregating populations were evaluated. These families were conducted by the bulk-within-families method and from the best, 154 lines were obtained and evaluated in the dry season of 2006 (F7: 9) and of 2007 (F7: 10), Coimbra - MG. The estimates of genetic and phenotypic parameters revealed variability among families. The method bulk within F3-derived families proved useful for bean breeding. The most promising lines that may be included in future tests of value for cultivation and use (VCU), and will possibly be recommended for planting in the state of Minas Gerais, were derived from the populations Vermelhinho/AN9022180//Vermelhinho/Vermelho2157, Vermelhinho//Vermelhinho/ IAPAR81,Vermelhinho/LR720982// Vermelhinho/AB136 and Vermelhinho/AB136//Vermelhinho/ Vermelho2157. [ABSTRACT FROM AUTHOR]