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Resumo -O objetivo deste trabalho foi avaliar os ganhos genéticos, preditos por meio de diferentes índices de seleção, em seis caracteres relacionados ao fruto, em 16 progênies de meios-irmãos de maracujá-amarelo. Foram utilizados: o índice clássico de Smith & Hazel (IC) e a distância genótipo-ideótipo de Cruz (IDGI), ambos com três pesos econômicos; o índice de ganhos desejados de Pesek & Baker (IGD); o índice livre de pesos e parâmetros de Elston (ILPP); e a seleção direta (SD). Observaram-se altas correlações genotípicas, de maior magnitude do que as fenotípicas, para algumas características, o que indica a existência de genes pleiotrópicos. Foram selecionadas cerca de 14% das plantas, para intercruzamento e formação de novo ciclo de seleção. Os critérios de seleção foram divergentes, inclusive para o mesmo índice de seleção com diferentes pesos econômicos, o que revela alta divergência das progênies estudadas. A SD permitiu a obtenção de ganhos preditos desejáveis para todos os caracteres, porém em magnitudes inferiores a outros índices. Embora o IC tenha possibilitado a obtenção de maiores ganhos genéticos em relação ao peso e ao número de frutos por planta, houve ganho negativo para alguns caracteres. O IDGI foi superior na predição de maiores ganhos genéticos, de forma equilibrada para todos os caracteres, enquanto o ILPP mostrou o pior desempenho.Termos para indexação: Passiflora edulis, meios-irmãos, melhoramento genético, variação genética. Selection on yellow passion fruit progenies by multivariate indicesAbstract -The objective of this work was to evaluate the genetic gains predicted through different selection indices in 16 half-sib progenies of yellow passion fruit, using six fruit characteristics. The selection criteria used were: the classical index of Smith & Hazel (CI) and the genotype-ideotype distance of Cruz (GID), both with three economic weights; the desired gain index of Pesek & Baker (DGI); the weight-free index of Elston (WFI); and the direct selection (DS). High genotypic correlations, of greater magnitude than the phenotypic ones, were found for some characteristics, which indicates the presence of pleiotropic genes. About 14% of the plants were selected for intercrossing and formation of a new cycle of selection. The selection criteria used were very different from each other, even for the same selection index with different economic weights, which shows the high progenies divergence. Desirable genetic gains were obtained with DS, but with lower magnitude than other indices. Although the CI was the criterion that showed the highest genetic gains for weight and number of fruits per plant, there were negative gains for some characteristics. The GDI was the best criterion to perform a greater predicted and balanced genetic gains for all the characteristics, while the WFI showed the worse performance.

High-throughput markers, such as SNPs, along with different methodologies were used to evaluate the applicability of the Bayesian approach and the multivariate analysis in structuring the genetic diversity in cassavas. The objective of the present work was to evaluate the diversity and genetic structure of the largest cassava germplasm bank in Brazil. Complementary methodological approaches such as discriminant analysis of principal components (DAPC), Bayesian analysis and molecular analysis of variance (AMOVA) were used to understand the structure and diversity of 1,280 accessions genotyped using 402 single nucleotide polymorphism markers. The genetic diversity (0.327) and the average observed heterozygosity (0.322) were high considering the bi-allelic markers. In terms of population, the presence of a complex genetic structure was observed indicating the formation of 30 clusters by DAPC and 34 clusters by Bayesian analysis. Both methodologies presented difficulties and controversies in terms of the allocation of some accessions to specific clusters. However, the clusters suggested by the DAPC analysis seemed to be more consistent for presenting higher probability of allocation of the accessions within the clusters. Prior information related to breeding patterns and geographic origins of the accessions were not sufficient for providing clear differentiation between the clusters according to the AMOVA analysis. In contrast, the F ST was maximized when considering the clusters suggested by the Bayesian and DAPC analyses. The high frequency of germplasm exchange between producers and the subsequent alteration of the name of the same material may be one of the causes of the low association between genetic diversity and geographic origin. The results of this study may benefit cassava germplasm conservation programs, and contribute to the maximization of genetic gains in breeding programs.

-The objective of this work was to identify sources of resistance to dry root rot induced by Fusarium sp. in cassava accessions. A macroconidial suspension (20 µL) of 11 Fusarium sp. isolates was inoculated in cassava roots, from 353 acessions plus seven commercial varieties. Ten days after inoculation, the total area colonized by the pathogen on the root pulp was evaluated by digital image analysis. Cluster analysis revealed the presence of five groups regarding resistance. The root lesion areas ranged from 18.28 to 1,096.07 mm 2 for the accessions BGM 1518 and BGM 556, respectively. The genotypes BGM 1042, BGM 1552, BGM 1586, BGM 1598, and BGM 1692 present the best agronomical traits.

Despite the widespread distribution of the Cassava common mosaic virus (CsCMV) in Brazil, little is known about the losses it causes in yield. The effect of CsCMV on different va-

RESUMOObjetivou-se selecionar híbridos diplóides (AA) de bananeira com base em três índices não paramétricos, a fim de orientar a seleção e aumentar o aproveitamento da variabilidade existente no Banco de Germoplasma de Bananeira da Embrapa Mandioca e Fruticultura Tropical. Foram avaliados 11 híbridos, no delineamento de blocos ao acaso, com quatro repetições. As parcelas constituíram-se de seis plantas, espaçadas de 2,5 m x 2,5 m, tendo na bordadura plantas da cultivar Pacovan. Tomaram-se dados dos seguintes caracteres: altura da planta, diâmetro do pseudocaule, número de filhos na floração, número de folhas na floração, ciclo da planta do plantio à emissão do cacho, presença de pólen, número de pencas, número de frutos, comprimento do fruto e resistência à Sigatoka-amarela. As médias desses 10 caracteres foram empregadas no cálculo dos índices multiplicativos, de soma de classificação e da distância genótipo-ideótipo. Os dois híbridos de melhor desempenho geral, o SH3263 e o 1318-01, foram classificados, respectivamente, em primeiro e segundo lugares pelos índices multiplicativos e de soma de classificação, enquanto o índice da distância genótipo-ideótipo os classificou em primeiro e quarto lugares respectivamente. Embora os três índices tenham demonstrado uma boa correspondência entre o desempenho geral dos híbridos e a sua classificação, os índices multiplicativo e de soma de classificação propiciaram classificação mais adequada desses híbridos. Palavras-chave:Musa spp, variabilidade, índice de seleção. ABSTRACT SELECTION OF (AA) DIPLOID BANANA HYBRIDS USING THREE NON-PARAMETRIC INDICESThe objective of the present study was to select diploids (AA) hybrids of banana based on three nonparametric indices as to guide the selection and increase the use of the variability present in the Banana Germplasm Bank of Embrapa Cassava and Tropical Fruits. Eleven hybrids were evaluated in random blocks with four replicates. The plots consisted of six plants spaced 2.5 m x 2.5 m whereas the border rows were from the Pacovan cultivar. The following characteristics were evaluated: plant height, pseudostem diameter, number of suckers, number of leaves during flowering, plant cycle from planting to bunch emission, presence of pollen, number of hands, number of fruits, fruit length and yellow-Sigatoka resistance. The average of these ten characteristics was used for calculating the multiplicative indices of sum of classification and genotype-ideotype distance. The two hybrids presenting best global performance SH3263 and 1318-01 ranked respectively, first and second by the multiplicative indices and sum of classification whereas the genotype-ideotype distance index ranked them first and fourth . Although in general, all three indexes presented good coherence between general performance of the hybrids and their classification, the multiplicative and sum of classification indexes provided a more adequate classification of these hybrids.

Abstract

-The objective of this work was to select the most informative morphoagronomic descriptors for cassava (Manihot esculenta) germplasm and to evaluate the ability of different methods to select the descriptors. Ninety-five accessions were characterized using 51 morphoagronomic descriptors. Data were subjected to a multiple correspondence analysis (MCA), whose information was used in the following four methods of descriptor selection: reverse order of the descriptor for the pth factorial axis of the MCA (Jolliffe); sequential, multiple correspondence analysis (SMCA); mean of the contribution orders of the descriptor in the first three factorial axes (C3PA); and C3PA method weighted by the respective eigenvalues of the full analysis (C3PAWeig). The correlations between the dissimilarity matrix with all descriptors and the most informative descriptors were high and significant (0.75, 0.77, 0.83, and 0.84 for C3PAWeig, C3PA, SMCA, and Jolliffe, respectively). The less informative descriptors were discarded, considering those common among the selection methods and relevant for the breeding interests. Therefore, 32 morphoagronomic descriptors with correlation between the dissimilarity matrices (r=0.81) were selected, due to their high capacity to discriminate cassava germplasm and to their ability to maintain some preliminary agronomic traits, useful for the initial characterization of the germplasm. Index terms: Manihot esculenta, descriptor selection, genetic resources, multiple correspondence analysis. Seleção dos descritores morfoagronômicos mais informativos para germoplasma de mandiocaResumo -O objetivo deste trabalho foi selecionar os descritores morfoagronômicos mais informativos para o germoplasma de mandioca (Manihot esculenta), e avaliar a capacidade de diferentes métodos em selecionar os descritores. Foram caracterizados 95 acessos com uso de 51 descritores morfoagronômicos. Os dados foram submetidos à análise de correspondência múltipla (ACM), cujas informações foram utilizadas nos seguintes quatro métodos de seleção de descritores: ordem inversa do descritor para o eixo fatorial pth da ACM (Jolliffe); análise de correspondência múltipla sequencial (ACMS); média das ordens de contribuição do descritor nos três primeiros eixos fatoriais (C3PE); e método C3PE ponderado pelos pesos dos respectivos autovalores da análise completa (C3PEPond). As correlações entre a matriz de dissimilaridade com todos os descritores e os descritores mais informativos foram altas e significativas (0,75, 0,77, 0,83 e 0,84 para C3PEPond, C3PE, ACMS e Jolliffe, respectivamente). Os descritores menos informativos foram descartados, tendo-se considerado apenas aqueles comuns entre os métodos de seleção e relevantes para os interesses do melhoramento. Assim, foram selecionados 32 descritores morfoagronômicos com correlação entre as matrizes de dissimilaridade (r=0,81), em razão de sua alta capacidade para discriminar o germoplasma de mandioca e de sua habilidade de manter alguns caracteres agronômicos preliminares, úteis para a...