Navegando por Autor "Nunes, Andrei Caíque Pires"
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Item Análises biométricas na otimização do melhoramento genético de Eucalyptus spp.(Universidade Federal de Viçosa, 2018-01-15) Nunes, Andrei Caíque Pires; Resende, Marcos Deon Vilela de; http://lattes.cnpq.br/4419738099312460As análises biométricas empregadas nos programas de melhoramento genético de espécies de Eucalyptus têm possibilitado a tomada de decisões por parte dos pesquisadores de forma acurada. Esses trabalhos vêm provendo relevantes informações sobre procedimentos e estratégias de melhoramento florestal. Levando em conta a necessidade de ampliação das informações acerca do entendimento de fenômenos biológicos impactantes na rotina de programas de melhoramento do eucalipto, esse estudo objetivou aplicar ferramentas biométricas para entendimento e resolução de problemas práticos, assim como propor novas estratégias para otimização de processos inerentes a esses programas. Dois diferentes experimentos clonais foram conduzidos na empresa CMPC Celulose Riograndense e um teste de progênies na empresa Cenibra. A partir do estudo do desempenho de clones de eucalipto em arranjos experimentais de parcela de planta única/single-tree-plot (PPU/STP) e parcelas quadradas/square plot (PQ/SP) realizados na CMPC Celulose Riograndense, foi possível constatar uma taxa de decréscimo de produtividade estimada para clones agressivos plantados em PPU em relação a PQ de 26%. Ademais, experimentos de eucalipto em PPU e PQ apresentam alta correspondência em termos de ordenamento genético. A partir da avaliação da habilidade competitiva de clones em PPU e PQ foram constatadas as seguintes classes de competição de clones: clones agressivos, homeostáticos e sensíveis à competição. Baseado nessas classes, foi proposto o plantio multiclonal otimizado, o qual propõe a combinação de clones agressivos e homeostáticos no plantio comercial, como uma forma de incrementar a produtividade média total do plantio. Avaliando-se o comportamento da interação genótipo por ambientes em testes clonais instalados na empresa CMPC Celulose Riograndense aos três e nove anos, constatou-se que o padrão de estratificação ambiental se modificou com o tempo para o caráter incremento médio anual (IMA, m 3 .ha -1 .ano -1 ). A causa da mudança da estratificação ao longo do tempo ocorreu devido ao caráter volumétrico em questão. Índices de seleção envolvendo caracteres de qualidade da madeira apresentam maior potencial de detecção de estratificação ambiental de forma precoce aos três anos. A estratificação em zonas de melhoramento se deu em virtude de similaridade de solos entre os ambientes avaliados. O uso de ferramentas biométricas possibilitou a otimização de seleção de um teste de progênies de famílias de irmãos completos de eucalipto instalados nas áreas da empresa Cenibra. Diversos cenários de montagem de pomares de sementes por mudas foram simulados. O cenário que maximizou os ganhos e minimizou a endogamia foi composto pelas sete melhores famílias com os melhores dez indivíduos em cada uma. Neste experimento constatou-se que os genótipos mais produtivos eram híbridos triplos, demonstrando a importância da busca pela heterose no melhoramento do eucalipto via cruzamento de genótipos superiores e divergentes geneticamente. Os resultados favoráveis em termos de ganho com seleção nas simulações dos cenários indicaram que, futuramente, este experimento poderá ser transformado em pomares de sementes por mudas. A correta utilização de ferramentas de Genética Quantitativa e Estatística permitiram a otimização dos programas de melhoramento do eucalipto propostos no presente trabalho, demonstrando a importância das análises biométricas na obtenção de resultados práticos, geração de novos conceitos e estratégias e tomadas de decisão acertadas pelo pesquisador.Item Application of hypergravity in Eucalyptus and Corymbia seeds(Ciência Rural, 2018-02-22) Nunes, Andrei Caíque Pires; Santos, Glêison Augusto dos; Santos, Marlise Araújo dos; Russomano, Thais; Santos, Osmarino Pires dos; Valente, Brígida Maria dos Reis Teixeira; Resende, Marcos Deon Vilela deThe aim of this study was to evaluate the growth responses of various Eucalyptus and Corymbia species subjected to different intensities of simulated hypergravity relative to the control. A centrifuge was used to simulate hypergravity. It was developed and built at the Centro de Microgravidade of the Pontifícia Universidade Católica do Rio Grande do Sul, Brazil. Seeds of five Eucalyptus and one Corymbia species (E. grandis, Eucalyptus globulus, Eucalyptus benthamii, Eucalyptus saligna, Eucalyptus dunnii, and C. maculata) were placed on moist germination paper in plastic containers and rotated at speeds simulating 5 Gz and 7 Gz for different lengths of time. Hypergravity technology significantly increased seedling production (diameter, height, and survival at 120 days) in nurseries. In E. globulus, the effects of hypergravity were significant at 7 Gz at all lengths of time (from 1 d to 9 days). Effects of hypergravity were significant in both E. benthamii and E. grandis at 7 Gz and 8 h exposure. Therefore, simulated hypergravity could be used in performance tests of Eucalyptus seedlings in early stages of development.Item Evaluation of different selection indices combining Pilodyn penetration and growth performance in Eucalyptus clones(Crop Breeding and Applied Biotechnology, 2016-11-03) Nunes, Andrei Caíque Pires; Resende, Marcos Deon Vilela de; Santos, Glêison Augusto dos; Alves, Rodrigo SilvaThe present study aimed to evaluate the selection indices efficiency for Pilodyn penetration combined with growth traits in Eucalyptus clones. It was carried out experiments in a randomized block design, with single tree plots and 30 replications. Diameter at breast height (DBH), total height (TH), and Pilodyn penetration as an indicator of basic density (BD) were measured. The volume was estimated. Based on predicted genotypic values, three indices presented the highest accuracies: I8 (based on partial correlation), I7 (based on the concept of multivariate BLUP) and I3 (based on two variables as ratio, which uses a third heritability estimate associated to the ratio DBH/BD, besides the two heritabilities of DBH and BD). Thus, it is possible to optimize the selection by combining properly the variables using their genetic control, precision and the relationships between them. The best options came from using only two no redundant traits DBH and BD.Item The first karyogram of a Bromeliaceae species: an allopolyploid genome(Plant Systematics and Evolution, 2013-06) Carvalho, Carlos Roberto; Nunes, Andrei Caíque Pires; Nogueira, Ester Ujiie; Gontijo, Andreia Barcelos Passos Lima; Clarindo, Wellington RonildoThe Bromeliaceae family has been traditionally distributed in the subfamilies Bromelioideae, Tillandsioideae and Pitcairnioideae. However, phylogenetic studies have provided other classifications, highlighting the need for analyses in order to characterize the genome of different species from this family. In this sense, the present work aimed to determine nuclear 2C-value and base composition, characterize the chromosomes and establish the karyogram of Pitcairnia flammea. Flow cytometry yielded 2C = 1.44 pg, AT = 64.28 % and GC = 35.72 % for this species, indicating its relatively small genome size. Despite reduced length and morphological similarity of the chromosomes, P. flammea metaphases presented well-spread chromosomes, with well-defined primary constriction, without chromatin damage and cytoplasmic background. These aspects allowed morphometric chromosomal characterization and assembly of the first karyogram of a Bromeliaceae species. The karyogram displayed 2n = 50 chromosomes, of which all were submetacentric. Karyomorphological analysis revealed grouped pairs of cytogenetically identical chromosomes (2–3, 4–5, 6–9, 10–17, 18–19, 20–23 and 24–25), plus one isolated chromosome (1), not identical to any other. This result suggests an allopolyploid origin for the P. flammea genome. Thus, the present investigation contributed with karyotype data for taxonomic and evolutionary aspects of this group.Item First karyotype description and nuclear 2C value for Myrsine (Primulaceae)... 163First karyotype description and nuclear 2C value for Myrsine (Primulaceae): comparing three species(Comparative Cytogenetics, 2017-03-13) Carvalho, Renata Flávia de; Amaral-Silva, Paulo Marcos; Spadeto, Micheli Sossai; Nunes, Andrei Caíque Pires; Carrijo, Tatiana Tavares; Carlos Roberto, Carvalho; Clarindo, Wellington RonildoCytogenetic studies in Primulaceae are mostly available for herbaceous species, and are focused on the chromosome number determination. An accurate karyotype characterization represents a starting point to know the morphometry and class of the chromosomes. Comparison among species within Myrsine, associating these data with the nuclear 2C value, can show changes that led the karyotype evolution. Here, we studied three Myrsine species [Myrsine coriacea (Swartz, 1788) Brown ex Roemer et Schultes, 1819, Myrsine umbellata Martius, 1841 and Myrsine parvifolia Candolle, 1841] that show different abilities to occupy the varied types of vegetation within the Brazilian Atlantic Forest. Cytogenetic characterization showed some individuals with 2n = 45 chromosomes for M. parvifolia and M. coriacea, with most individuals of the three species having 2n = 46. The first karyograms for Myrsine were assembled and presented morphologically identical and distinct chromosome pairs. In addition, differences in the mean 2C nuclear value and chromosome morphometry were found. Therefore, the first description of the Myrsine karyotype has been presented, as well as the nuclear 2C value. The procedures can be applied to other Myrsine species for future investigations in order to better understand its effects on the differential spatial occupation abilities shown by the species in Brazilian Atlantic Forest.Item From chromosome doubling to DNA sequence changes: outcomes of an improved in vitro procedure developed for allotriploid “Híbrido de Timor” (Coffea arabica L. × Coffea canephora Pierre ex A. Froehner)(Plant Cell, Tissue and Organ Culture (PCTOC), 2017-11) Sattler, Mariana Cansian; Carvalho, Carlos Roberto; Nunes, Andrei Caíque Pires; Sanglard, Natália Arruda; Silva, Paulo Marcos Amaral; Oliveira, Stéfanie Cristina de; Soares, Taís Cristina Bastos; Clarindo, Wellington RonildoSince 1966, chromosome doubling has been performed mainly in vitro, associating anti-tubulin treatment and different plant tissues showing proliferative cells. Despite the achieved improvements, some bottlenecks have been pointed out, such as the low rate of polyploids and high rate of mixoploid plantlets. To overcome these hurdles, some approaches have indicated that indirect somatic embryogenesis (ISE) constitutes an alternative trigger for chromosome doubling, especially for homoploid and anorthoploid germplasms. In this way, a guideline has been developed for hexaploidization of the Coffea line “Híbrido de Timor” (HT) ‘CIFC 4106’ (anorthoploid, 3x = 33 chromosomes, 1C = 2.10 pg, Coffea canephora × Coffea arabica) from friable embryogenic calli (FEC) treated with colchicine. From this, a relatively high percentage (49.3%) of HT hexaploids (6x = 66 chromosomes, 2C = 4.20 pg) was obtained, without recovery of mixoploids. Besides confirmation of endomitosis induction through the obtained hexaploids, SSR markers revealed that the FEC/colchicine strategy also resulted in loss of allelic diversity in 39 regenerated HT plantlets, demonstrating its genotoxic effect. Considering these results, the present procedure resolved the main bottlenecks for chromosome doubling, which have been reported since the discovery and isolation of the anti-tubulin colchicine in 1930. Hexaploid HT plantlets have enriched Coffea germplasm banks as a new genetic resource since the resolution of their karyotype and DNA sequence. Just as the true allotetraploid C. arabica and the allotriploid HT ‘CIFC 4106’, the hexaploid HT is relevant to investigate the genomic and phenotypic changes arising from polyploidization events.Item Genetic control and genotype-by-environment interaction of wood weight in Eucalyptus clones in the state of Rio Grande do Sul, Brazil(Revista Árvore, 2016-09-02) Santos, Gleison Augusto; Nunes, Andrei Caíque Pires; Resende, Marcos Deon Vilela; Silva, Luciana Duque; Higa, Antonio; Assis, Teotônio FranciscoThe present study aimed to evaluate the genetic control and genotype-by-environment interaction in wood weight of Eucalyptus clones in four environments located in the state of Rio Grande do Sul, Brazil, aiming to select superior genotypes. In 2007, a network of clonal tests was established with 864 clones of Eucalyptus. At three years of age, diameter at breast height and total height were measured, as was depth of Pilodyn penetration, for indirect inference of wood basic density. The mean annual increment of dry weight (MAIweight) was calculated. Individual heritability of 0.148 and of 0.48 was found for MAIweight and Pilodyn penetration depth, respectively. The genetic correlation between environments ranged from 0.503 to 0.926 for all traits. The genotype-by-environment interaction was significant for the MAIweight index (0.533). From the environment interaction analysis, 3 "improvement areas" were defined for the trait MAIweight. The grouping of the traits wood density and volume to create a wood weight index was essential for a more accurate selection, since there was a change of 37% compared to the ranking of clones for volume. The simultaneous selection for stability and adaptability provided higher gains when compared to selection based on predicted genotypic values between environments. Moreover, MHPRVG allowed an increase in gains compared to the control. Thus, the five best clones were selected based on these criteria: 39912 (E. urophylla), 39659 (E. urophylla), 6808 (E. grandis), 36190 (E. saligna), 39407 (E. grandis x E. urophylla).Item Genetic divergence of native palms of Oenocarpus distichus considering biometric fruit variables(Scientific Reports, 2019) Mendes, Gleidson Guilherme Caldas; Gusmão, Mônica Trindade Abreu de; Martins, Thales Guilherme Vaz; Rosado, Renato Domiciano Silva; Sobrinho, Rayanne Savina Alencar; Nunes, Andrei Caíque Pires; Ribeiro, Wellington Souto; Zanuncio, José ColaOenocarpus distichus presents economic, ecological, and dietary potential for pulp market processed in natura. Germplasm conservation and genetic improvement depend on genetic divergence studies. The objective was to quantify genetic divergence in a native population of O. distichus genotypes based on fruit biometrics. The fruit length and width, fruit mass, pulp and seed, pulp and almond thickness, and pulp yield per fruit were evaluated. All fruit biometric characteristics of O. distichus palms show genetic variability. Genetic variations among genotypes are essential for predicting heredity and heterosis, which are essential for improving O. distichus production. Pulp yield and seed mass were negatively correlated. Almond thickness and pulp, seed mass and transverse diameter were positively correlated. Genetic distances between pair of genotypes ranged from 0.07 to 48.10 with three genetically distinct groups. The seed mass, almond thickness and transverse diameter contributed to genetic divergence. Heritability estimates the genetic control that can be obtained from O. distichus germplasm. Correlations between the variable pair reduce the evaluation effort and the resources to measure the genotype allocations in heterogeneous groups presenting high genetic variability. This makes it possible to select individuals for hybridization programs with F1 generation gains. Correlation and relative contribution networks, based on relationships graphical between fruit biometric characteristics, allow the variables selection with less effort and fewer measurements. O. distichus fruit biometric characters are efficient to quantify genetic divergence between genotypes.Item Qualidade da madeira, critérios de seleção e interação genótipos x ambientes de clones de Eucalyptus no Rio Grande do Sul(Universidade Federal de Viçosa, 2015-07-28) Nunes, Andrei Caíque Pires; Resende, Marcos Deon Vilela de; http://lattes.cnpq.br/4419738099312460Os ensaios foram conduzidos nas áreas da empresa CMPC Celulose Riograndense, em quatro diferentes ambientes. Em cada sítio, um experimento no delineamento de blocos ao acaso foi estabelecido, com parcela de arvore única e 30 repetições. Aos três anos de idade, foram mensurados o diâmetro a altura do peito (DAP), altura total das arvores (Ht) e a profundidade de penetração do Pilodyn (Db), para obtenção do volume (Vol) e estimação indireta da densidade básica da madeira, respectivamente. Para o estudo da interação G x A, dois índices de peso de madeira (DAPxDb e VolxDb) foram criados. Com os valores genotípicos de cada variável analisada, índices de pesos de madeira foram propostos utilizando-se como ponderadores as correlações genéticas entre as variáveis, acurácias de predição, herdabilidades, correlações parciais e os efeitos diretos da análise de trilha. O índice DAPxDb (hºg = 0,23) apresentou interação G x A significativa e, a partir da análise de interação dos ambientes par a par, duas “zonas de melhoramento” foram definidas para DAPxDb. Na análise de critérios de seleção, três índices foram os mais eficientes, em virtude de suas acurácias elevadas. O índice l2, baseado na correlação parcial do caráter objetivo peso de madeira e os caracteres auxiliares DAP e Db, l1 (conceito de blup multivariado) e o índice IVR DAPxDb baseado no conceito de variável relacional, com acurácias de 1,00, 0,97 e 0,96, respectivamente. Dessa forma, constatou-se que e possível efetuar a seleção multicaracterística para peso de madeira em Eucalyptus, com alta eficiência, sem a necessidade de estabelecer procedimentos complexos para modelos multivariados mistos. A medição precisa do DAP juntamente com a Db no índice DAPxDb foi fundamental na obtenção de apenas duas “zonas de melhoramento”.Item Statistical strategies design based on competition classes of Eucalyptus clones(Industrial Crops and Products, 2018-11-15) Nunes, Andrei Caíque Pires; Santos, Osmarino Pires dos; Santos, Glêison Augusto dos; Resende, Marcos Deon Vilela deA detailed knowledge of different types of trial designs is essential to establish adequate Eucalyptus breeding strategies. This study compared clone’s development in single-tree-plot (STP) and square-plot (SP) experiments to analyze differences in estimated genetic parameters, ranking, predicted genotypic value and competition ability. Experiments were carried out in the CMPC Celulose Riograndense Company, in the state of Rio Grande do Sul, Brazil. A total of 239 clones were used, 214 of which were common to the STP and SP trials. Results showed that STP is a very promising trial design for accurately ranking the genotypes. The STP and SP tests showed high coincidence in ranking selection, but the best clone yields were overestimated in the STP trial and the yields of the worst clones were underestimated in the STP trial. Therefore, an STP design should be used in initial and intermediary clonal tests, and an SP design should be used in the final stages of a breeding program, in order to estimate the clonal yield at a semi-operational scale. The estimated yield decreasing of clones planted in SP compared to STP is 26%. This value should be used in future STP experiments in the same area and with the same germplasm evaluated in this work. In addition, this research identified classes of aggressive clones, sensitive clones, and clones that were homeostatic to the competitiveness effect. Based on this classification, the optimized multiclonal plantation were suggested aiming to maximize yield by using aggressive and homeostatic clones.