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URI permanente para esta coleçãohttps://locus.ufv.br/handle/123456789/11845
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Item Nova subspécie de Caprimulgus (Linnaeus) (Aves, Caprimulgidae) do Espírito Santo, Brasil(Revista Brasileira de Zoologia, 1995) Ribon, RômuloA population of a small and dark nightjar was discovered at Colatina, Espírito Santo, and has been identified by its voice and pattern of coloration as a new subspecies of the Pygmy Nightjar Caprimulgus hirundinaceus (Spix, 1825). This represents a considerable range expansion for this poorly known species, formerly considered endemic to the xeric "caatinga" region of Northeastern Brazil. However, other populations may exist. Colatina's birds live on exposed dark rocks with which their plumage harmonizes.Item Aspectos da biologia de Euplusia violacea (Blanchard) (Hymenoptera, Apidae, Euglossini)(Revista Brasileira de Zoologia, 1997) Peruquetti, Rui Carlos; Campos, Lúcio Antônio de OliveiraNests of orchid bee Euplusia violacea (Blanchard, 1840) colleted in trap-nests and in the wood of a construction in Viçosa, Minas Gerais (20º45'30"S, 42º52'05"W), Brazil, were studied under laboratory condictions. Some aspects of the biology of these bees were observed, such as sex-ratio, development time, Iongevity and others. Some aspects of the behavior of E. violada were also studied.Item Abelhas Euglossini (Apidae) de áreas de Mata Atlântica: abundância, riqueza e aspectos biológicos(Revista Brasileira de Zoologia, 1999) Peruquetti, Rui Carlos; Campos, Lúcio Antonio de Oliveira; Coelho, Claudia Diniz Pinto; Abrantes, Célio Vicente Machado; Lisboa, Luciane Cristina de OliveiraCollection data of Euglossinae males from Parque Estadual do Rio Doce (PERD) and Viçosa, both areas with remnants of Atlantic Rain Forest (Mata Atlântica) in Minas Gerais state, Brazil are presented. Comparisons made among three fragments with different sizes and states of disturbance from Viçosa showed differences in abundance of most common species and apparently, Eulaema nigrita Lepeletir, 1841 can be an useful indicator of disturbed sites. Some populations of euglossine bees seems to be restrict to a forest fragment, there being few or no flow of individuals or species of one fragment to another, even when they are only 1 km apart. 15 species of euglossines were sampled in PERD, and the most abundant was Eulaema cingulata (Fabricius, 1804). At Viçosa, 10 species were sampled, E. nigrita was the predominant one. Methyl salicylate attracted no males at both sites, in spite of large numbers of species and individuals sampled using this bait in other regions. The majority of species and individuals were collected in the rainy season. Only 0,58% of sampled males carried orchid pollinia (Catasetum Richard, Cycnoches Lindley and Coryanthes Hook) on their bodies. Emergence data of four species of Euglossa Latreille, 1802 reared from trap nests suggest that sex ratio in Euglossini is not a constant within the tribe. A list of 57 euglossine species now known to occur in Mata Atlântica are offered.Item Heterogeneidade estrutural e diversidade de pequenos mamíferos em um fragmento de mata secundária de Minas Gerais, Brasil(Revista Brasileira de Zoologia, 1995) Paglia, Adriano Pereira; Marco Júnior, Paulo de; Costa, Fernando Martins; Pereira, Ronaldo Fernandes; Lessa, GiseleThe aim is to determine the relationship between the diversity of small mammals and the structural heterogeneity and/or secondary successional stages in an Atlantic forest fragment at Viçosa (Minas Gerais). We used Sherman and hook live traps to sample this fauna, monthly from may 1992 to april 1993 in three areas: an abandoned plantation of Melinis minutiflora (campo) and two distinct forest areas (capoeira and mata). The structural heterogeneity was determined as a function of the presence of dead trees, pioneer species, epiphytes, the distances between trees, the tree height and basal area measured by a modified quadrant sample method (Cottam & Curtis 1945). lt was sampled a total of 340 individuals belonging to 17 species. The homogeneous plantations had the highest diversity (H' = 1,67). Among the two forests stands the less heterogeneous capoeira had similar diversity (H' = 1,19) than the more heterogeneous stand, the mata (H' = 1,13). The unexpected higher diversity and species richness in the more homogeneous habitat may be explained by some hidden factor which decrease the competition for resources in this community.Item Theory and analysis of partial diallel crosses(Genetics and Molecular Biology, 1999-12) Viana, José Marcelo Soriano; Cruz, Cosme Damião; Cardoso, Antonio AméricoThis study presents theory and analysis of partial diallel crosses based on Hayman's methods. This genetic design consists of crosses among two parental groups. It should be used when there are two groups of parents, for example, dent and flint maize inbred lines, and the breeder is not interested in the assessment of crosses between parents of the same group. Analyses are carried out using data from the parents and their F1 hybrids allowing a detailed characterization of the polygenic systems under study and the choice of parents for hybridization. Diallel analysis allows the estimation of genetic and non-genetic components of variation and genetic parameters and to assess the following: genetic variability in each group; genotypic differences between parents of distinct groups; if a parent has a common or a rare genotype in the group to which it does not belong; if there is dominance; if dominant genes increase or decrease trait expression (direction of dominance); average degree of dominance in each group; the relative importance of mean effects of genes and dominance in determining a trait; if, in each group, the allelic genes have the same frequency; if genes are equally frequent in the two groups; the group with the greatest frequency of favorable genes; the group in which dominant genes are most frequent; the relative number of dominant and recessive genes in each parent; if a parent has a common or a rare genotype in the group to which it belongs, and the genotypic differences between parents of the same group. An example with common bean varieties is considered.Item Association between Griffing's diallel and the adaptability and stability of Eberhart and Russel(Genetics and Molecular Biology, 1999-09) Cruz, Cosme Damião; Pacheco, Cleso Antônio Patto; Santos, Manoel Xavier dosThe objective of the present work was to provide a methodology to study the inheritance of adaptability and stability through the breakdown of Eberhart and Russell regression coefficients and regression deviations in effects due to the mean and additive genetic effects (g i’s and g j’s ) as well as dominance effects (s ij’s ) of Griffing ́s methodology, when the diallel is conducted in several environments. It was concluded that the adaptability and stability parameters are determined in the same manner as are genetic effects. So an F1 cross inherits half the general combining ability (GCA) mean effect from each parent, while the effects due to specific combining ability (SCA) are subjected to the same considerations relative to s ij’s , i.e., they are dependent on specific com- binations.Item Estimation of genetic parameters in the square lattice analysis(Bragantia, 1999) Viana, José Marcelo Soriano; Regazzi, Adair JoséThis paper shows how to obtain unbiased estimates of genetic parameters of base populations, e.g., genotypic variance among families, heritability on a family mean basis, genotypic correlation and direct and indirect expected genetic gains, when the sampled families were evaluated in square lattice experiment. The theoretical part presents the variance and covariance components of the intra-block analysis of square lattice and the estimators of the components associated to treatment effect, considering the ordinary least squares method. In the analysis with treatments not corrected for blocks/replications, the estimator of the component due to treatment effect is equal to that of the analysis considering the complete block model. Experimental data from a breeding program of Eucalyptus pyrocarpa were used for genetic analysis. The high estimates of narrow sense heritabilities and additive genetic correlation, related to height and diameter, indicate that selection of the superior families will be effective in changing the means of the base population.Item Estimation of genetic parameters in the analysis of square lattice experiment group(Bragantia, 1999) Viana, José Marcelo Soriano; Regazzi, Adair JoséAiming to demonstrate how to obtain unbiased estimates of genetic parameters of base populations, unaffected by genotype x environment effects, this paper presents the variance and covariance components of the intra-block analysis of a group of square lattice experiments and the estimators of the components associated to treatment effect. Random model and mixed models with environment effect fixed and other effects random are considered. In the analysis with treatments not corrected for locks/replications/environments, the estimators of the variance and covariance components due to treatment effect are different from those of the analysis considering the complete block model. Data from two experiments of a breeding program of Eucalyptus pyrocarpa were used for genetic analysis. The analysis of variance of height and diameter indicated absence of interaction between progeny and environment. Due to this result, the prediction of the direct and indirect genetic gains was based on the mean of the two environments. The high estimates of narrow sense heritabilities and additive genetic correlation indicate that selection of the superior families will be effective in changing the means of the base population for both traits.Item Programa GENES - aplicativo computacional em estatística aplicada à genética(Genetics and Molecular Biology, 1998-03) Cruz, Cosme DamiãoO principal objetivo do software GENES é ajudar pessoas que trabalham com análise genética e processamento de dados em programas de melhoramento, usando vários modelos biométricos. Este software tem várias janelas de ajuda que são muito amigáveis para o usuário. Mais informações sobre este programa estão disponíveis no livro "Programa GENES - Aplicativo Computacional em Genética e Estatística, 442. 1997". Pedidos de compra são bem-vindos no seguinte endereço: editora@mail.ufv.br. As cópias shareware do software GENES estão disponíveis em http://www.genetica.dbg.ufv.br.Item The role of the external mycelium of arbuscular mycorrhizal fungi in the carbon transfer process between plants(Mycological Research, 1993-07) Martins, Marco A.An experiment was carried out to evaluate the relative contribution of the pathways involved in the carbon transfer process between Lolium perenne plants using 14CO2. The results showed that the direct transfer pathway via mycorrhizal hyphae contributed 46%, the indirect transfer pathway mediated by the mycorrhizal mycelium 15%, and the indirect transfer pathway, not mediated by the mycorrhizal mycelial net, 39%.