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Organogênese in vitro a partir de explante caulinar na regenera??o de clones de Eucalyptus grandis W. Hill ex Maiden X E. urophylla S. T. Blake
Alves, Elisa Cristina Soares de Carvalho;Xavier, Aloisio;Otoni, Wagner Campos;
Revista árvore , 2004, DOI: 10.1590/S0100-67622004000500003
Abstract: with the objective of testing in vitro regeneration through organogenesis from stem explants of three hybrid clones of eucalyptus grandis x eucalyptus urophylla, the effects of the growth regulators tdz [1-phenil-3-(1, 2, 3-thiadiazol-5-il)urea], bap (6-benzilaminopurine) and naa (naphthalene acetic acid) were evaluated. in general, a differentiated clone response in relation to intensity, texture, color and oxidation degree of calli was observed due to growth regulator treatments. the best results in callus formation were recorded for the treatments with the combination tdz (0,5 mg l-1) and ana (0,1 mg l-1), achieving 100% of callus formation from the stem explants. compact node structures appeared mainly in the extremities of the stem explants, being those areas responsible for the regeneration of adventitious buds. the best regeneration response was obtained with 1,0 mg l-1 bap.
Methods of asepsis for in vitro establishment and germination of Eucalyptus grandis  [cached]
Berenice Kussumoto Alcantara,Gilvano Ebling Brondani,Ant?nio Natal Gon?alves,Marcílio de Almeida
Journal of Biotechnology and Biodiversity , 2011,
Abstract: Technical and scientific studies have been conducted for the cultivation of Eucalyptus, with special attention tolarge-scale clonal propagation. However, in some studies are necessary to obtain aseptic material from seeds, andas far as we are aware efficient protocols of asepsis for this purpose are still not available. Therefore, this studyaimed to define a protocol for sterilization of seeds of Eucalyptus grandis for in vitro establishment andgermination. Four methods of sterilization were tested using different application sequences of the disinfectants, asbenomyl fungicide, hydroalcoholic solution (70% v/v) and sodium hypochlorite (NaOCl). The experiment wasconducted in completely randomized design with five repetitions. The percentage of establishment andcontamination were evaluated at the end of the experiment. Washing with sterile water and 70% alcohol for 30 s,2.5% sodium hypochlorite for 20 min, 1% benomyl for 20 min and three washes with sterile water was the bestmethod found, accounting to 87.5% of establishment.
In vitro ectomycorrhiza formation by monokaryotic and dikaryotic isolates of Pisolithus microcarpus in Eucalyptus grandis
Costa, Maurício Dutra;Campos, André Narvaes da Rocha;Santos, Matheus Loureiro;Borges, Arnaldo Chaer;
Revista árvore , 2010, DOI: 10.1590/S0100-67622010000300001
Abstract: the formation of ectomycorrhizas by monokaryotic and dikaryotic isolates of pisolithus microcarpus (cooke & massee) g. cunn. in eucalyptus grandis w. hill ex maid. was studied by in vitro synthesis in petri dishes. the formation of ectomycorrhizas was observed for all strains tested. ectomycorrhizas formed by the monokaryotic strains presented a sheath of hyphae around the roots and a hartig net limited to the epidermis layer, typical of the angiosperm ectomycorrhizas. colonization rates, a measure of the number of ectomycorrhizas in relation to the total number of lateral root tips, varied from 23 to 62%. some monokaryotic strains stimulated the formation of lateral roots, promoting increases of up to 109% above the control. the presence of some of the isolates in the in vitro synthesis medium stimulated the production of thicker lateral root tips. the dimensions of the lateral roots tips and ectomycorrhizas varied from one isolate to the next, indicating a variation in their capacity to provoke morphological changes in the host plant roots. the dikaryotic strain m5m11 presented higher values for lateral root yield, number of ectomycorrhizas, and colonization percentage than the corresponding monokaryotic strains, m5 and m11. this indicated the possibility of selecting compatible performing monokaryotic isolates for the yield of superior dikaryotic strains. the set of monokaryotic strains tested varied greatly in their ability to colonize e. grandis roots and cause secondary metabolism-related morphological changes in roots, providing a wealth of model systems for the study of genetic, physiological, and morphogenetic processes involved in pisolithus-eucalyptus ectomycorrhiza formation.
Aclimatiza??o ex vitro de plantes propagadas pela enxertia in vitro de clones de Eucalyptus urophylla x E. grandis
Bandeira, Fabiana Schmidt;Xavier, Aloisio;Otoni, Wagner Campos;Lani, Elisonete Ribeiro Garcia;
Revista árvore , 2007, DOI: 10.1590/S0100-67622007000500001
Abstract: this work aimed to evaluate the survival and growth of two eucalyptus urophylla x e. grandis clones obtained by in vitro grafting technique during the ex vitro acclimatization stage. grafted plants were obtained from rootstocks from seedlings of in vitro-germinated eucalyptus grandis and e. urophylla, and apexes from stem tips (average 10 mm) of two micropropagated eucalyptus urophylla x e. grandis clones. after 50 days of in vitro culture, the plants were transferred to ex vitro conditions and plant survival and growth were evaluated. high grafting survival rates (87%) were recorded at 70 days in the ex vitro condition, as well as good height growth. clones showed similar performance in relation to the used stocks, indicating that the chosen acclimatization process was efficient.
Enxertia in vitro na propaga??o de clones de Eucalyptus urophylla e E. grandis
Bandeira, Fabiana Schmidt;Xavier, Aloisio;Otoni, Wagner Campos;Dias, José Maria Moreira;
Pesquisa Agropecuária Brasileira , 2006, DOI: 10.1590/S0100-204X2006000200006
Abstract: the objective of this work was to evaluate the efficiency of the in vitro grafting in the propagation of two eucalyptus urophylla and e. grandis hybrid clones. juvenile stocks obtained from seeds of e. grandis and e. urophylla germinated in vitro were used. the grafted plants showed success up to 93% at 50 days for the scion and stock combinations. the highest final plant height values were observed when the stock was e. urophylla. histologic analysis showed that cicatrized callus in the connection region was successfully followed by vascular recomposition in different combinations among scion with rootstocks.
Multiplica??o in vitro de Eucalyptus grandis sob estímulo com benzilaminopurina
Andrade, Wirifran Fernandes de;Almeida, Marcílio de;Gon?alves, Ant?nio Natal;
Pesquisa Agropecuária Brasileira , 2006, DOI: 10.1590/S0100-204X2006001200005
Abstract: the objective of this work was to evaluate the effect of pulse on in vitro multiplication of eucalyptus grandis. interactions were evaluated among bap concentrations (0, 200, 400 and 600 mg l-1), exposure time (1, 2 and 3 hours), ph values (3 and 5.8), and explant morphological changes. fresh weight of the explants was determined weekly. at 21 days of culture, valuations were made of the number of shootings per treatment, number of shootings obtained per explant (multiplication rate), and seedlings rescue was accomplished for histological analysis. the ph values did not present any interaction with the other factors. the most significant treatments on e. grandis shoot multiplications were 200 mg l-1 of 6-bap during 1 and 2 hours. there was an intensification of cell division in the cortical parenchyma and procambium, represented by the arising of meristems in response to 200 mg l-1 of bap treatment, during 1 and 2 hours. the use of the pulse on in vitro multiplication of e. grandis is feasible.
Controle genético da eficiência de utiliza??o de fósforo em famílias de meios-irm?os de Eucalyptus grandis, em casa de vegeta??o
Paula, Rinaldo Cesar de;Paula, Nadia Figueiredo de;Valeri, Sérgio Valiengo;Cruz, Mara Cristina Pess?a da;Tolfo, Ana Lídia Tonani;
Revista árvore , 2003, DOI: 10.1590/S0100-67622003000100004
Abstract: a greenhouse experiment was carried out to evaluate the genetic variability in the efficiency of phosphorus utilization in 18 half-sib families of eucalyptus grandis w. hill ex maiden, submitted to three phosphorus levels (0, 200 and 400 mg/dm3 p2o5). the experiment was arranged in a completely randomized design, following an 18 x 3 factorial scheme totaling 54 treatments and three replications of two plants per pot, containing 7 dm3 of soil grown until 120 days after transplant. height, collar diameter; and dry matter of roots, stems, branches, leaves, shoots and total dry matter, shoot-root rate and p concentration, content and utilization efficiency in the leaves and in the stems were evaluated. the families responded positively to fertilization, differently for each characteristic, with a tendency to stabilize at the highest level. the highest p absorption was observed when 400 mg/dm3 p2o5 were added. however, this was not accompanied by increased dry matter production, resulting in lower p utilization efficiency under this condition. in general, the genetic material evaluated presented low genetic variability, but it was possible to identify promising materials for the characteristics evaluated.
Controle genético da eficiência de utiliza o de fósforo em famílias de meios-irm os de Eucalyptus grandis, em casa de vegeta o  [cached]
Paula Rinaldo Cesar de,Paula Nadia Figueiredo de,Valeri Sérgio Valiengo,Cruz Mara Cristina Pess?a da
Revista árvore , 2003,
Abstract: Com o objetivo de avaliar a existência e a magnitude da variabilidade genética para a eficiência de utiliza o de fósforo, conduziu-se o experimento em casa de vegeta o, usando 18 famílias de meios-irm os de Eucalyptus grandis W. Hill ex Maiden, submetidas a três doses de fósforo (0, 200 e 400 mg/dm3 de P2O5). O experimento foi disposto em delineamento inteiramente casualizado, no esquema fatorial 18 x 3, num total de 54 tratamentos, com três repeti es de duas plantas, e foi conduzido em vasos com 7 dm3 de solo. Aos 120 dias após o transplantio das mudas, foram avaliados a altura e o diametro do coleto; a massa seca de raízes, caule, galhos, folhas, parte aérea e total, a rela o raiz-parte aérea; e o teor, o conteúdo e a eficiência de utiliza o de fósforo nas folhas e no caule das plantas. As famílias responderam positivamente à aduba o fosfatada, porém de forma diferenciada para cada característica, apresentando tendência de estabiliza o na maior dose testada. A adi o de 400 mg/dm3 de P2O5 causou maior absor o de P, porém n o proporcionou a maior produ o de matéria seca, resultando em menor eficiência de utiliza o de P nesta condi o. Em geral, o material testado apresentou baixa variabilidade genética, mas foi possível identificar materiais promissores para as características avaliadas.
Efeito "in vitro" de antibióticos e rizobactérias no controle de bactérias fitopatogênicas ao Eucalyptus spp.
Cunha, Jeane de Fátima;Picoli, Edgard Augusto de Toledo;Alfenas, Acelino Couto;Gon?alves, Rivadalve Coelho;
Revista árvore , 2006, DOI: 10.1590/S0100-67622006000600001
Abstract: diseases caused by bacteria represent a new challenge for eucalyptus spp. and may also limit the use of susceptible clones. our study aimed at an evaluation of the efficiency of antibiotics and rhizobacteria in inhibiting "in vitro" growth of phytopathogenic bacteria isolates in eucalyptus spp. during the nursery stage and in the field. the antibiotic amicacine sulfate and rhizobacterium s1 (bacillus subtilis) stood out inhibiting the growth of the phytopathogenic isolate ip1-05 (pseudomonas chichorii), whereas cefoxitin caused a greater inhibition of the isolates bsv16 and rvv11 (rhizobium sp.). the commercial antibiotics for agricultural use mycoshield (oxitetracycline) and agrimycin (estreptomycin and tetracycline) were little effective. this study offers a base for alternatives of biological control of bacterial diseases in eucalyptus spp. nursery seedlings.
Combining ability of elite clones of Eucalyptus grandis and Eucalyptus urophylla with Eucalyptus globulus
Bison, Odair;Ramalho, Magno Antonio Patto;Rezende, Gabriel Dehon Sampaio Pe?anha;Aguiar, Aurélio Mendes;Resende, Marcos Deon Vilela de;
Genetics and Molecular Biology , 2007, DOI: 10.1590/S1415-47572007000300019
Abstract: in brazil, eucalyptus breeding programs for cellulose production has used two species, eucalyptus grandis and eucalyptus urophylla. nevertheless, it would be useful to introgress alleles from other species to improve wood quality and volume. the objective of this research was to evaluate the hybrid potential of elite clones of e. grandis and e. urophylla from the aracruz celulose company s. a. with eucalyptus globulus clones. to do so, six elite clones were crossed with ten e. globulus clones in a half-diallel mating design. the resulting hybrid combinations as well as the four check clones were evaluated in randomized complete block experiments with single plant plots and 40 replicates from september to october 2001 at three brazilian sites, aracruz and s?o mateus in the espírito santo state and caravelas in bahia state. two years later the circumference at breast height (cbh) and the wood density (wd) were measured. the means were submitted to diallel analysis according to the griffing method (1956), adapted by geraldi and miranda filho (1988). although the number of clones involved was small, the crossings of elite clones of e. grandis and e. urophylla with clones of e. globulus were promising, especially for wood quality gains.
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