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Validation of reference genes from Eucalyptus spp. under different stress conditions
Jullyana Cristina Magalh?es Silva Moura, Pedro Araújo, Michael dos Brito, Uiara Souza, Julianade Oliveira Fernandes Viana, Paulo Mazzafera
BMC Research Notes , 2012, DOI: 10.1186/1756-0500-5-634
Abstract: Eucalyptus globulus Labill, Eucalyptus urograndis (hybrid from Eucalyptus urophylla S.T. Blake X Eucalyptus grandis Hill ex-Maiden) and E. uroglobulus (hybrid from E. urograndis X E. globulus) were subjected to different treatments, including water deficiency and stress recovery, low temperatures, presence or absence of light, and their respective controls. Except for treatment with light, which examined the seedling hypocotyl or apical portion of the stem, the expression analyses were conducted in the apical and basal parts of the stem. To select the best pair of genes, the bioinformatics tools GeNorm and NormFinder were compared. Comprehensive analyses that did not differentiate between species, treatments, or tissue types, showed that IDH (isocitrate dehydrogenase), SAND (SAND protein), ACT (actin), and A-Tub (α-tubulin) genes were the most stable. IDH was the most stable gene in all of the treatments.Comparing these results with those of other studies on eucalyptus, we concluded that five genes are stable in different species and experimental conditions: IDH, SAND, ACT, A-Tub, and UBQ (ubiquitin). It is usually recommended a minimum of two reference genes is expression analysis; therefore, we propose that IDH and two others genes among the five identified genes in this study should be used as reference genes for a wide range of conditions in eucalyptus.The genus Eucalyptus belongs to the Myrtaceae family, which consists of approximately 600 species and subspecies, exhibits physiological plasticity with worldwide dispersion and successfully grows in different regions. Eucalyptus is a major source of cellulose for manufacturing paper [1] and globally, Brazil ranks first in the production of short fibre cellulose [2]. Due to its economic importance, the genome sequencing of the species Eucalyptus grandis was recently completed [3].E. globulus and E. grandis are the two main species cultivated in the world [4]. Among the existing species, E. globulus is known for it
Estimativa de volume de madeira em plantios de Eucalyptus spp. utilizando dados hiperespectrais e dados topográficos
Canavesi, Vanessa;Ponzoni, Flávio Jorge;Valeriano, Márcio Morisson;
Revista árvore , 2010, DOI: 10.1590/S0100-67622010000300018
Abstract: the availability of orbital hyperspectral data has brought new perspectives to both academic and corporative sectors solving demands in forestry science. the main objective of this work was to evaluate the potential of hyperion eo-1 hyperspectral data to quantify the biophysical timber volume in eucalyptus spp stands and the effect of hill shading in that quantification. for this, the correlations between spectral data and timber volume were performed following the use of multiple linear regression models as the descriptors of the relationships established. the relief effect on the eucalyptus spp. canopy reflectance was taken into account. the hyperion eo-1 data were converted to brf surface values, which were considered the basis of the entire work. the study area was located in the municipality of cap?o bonito (the state of s?o paulo, brazil) and included eucalyptus spp. stands managed by the votorantim papel e celulose company (vcp). spectral samples were collected in different topographic conditions. in the establishment of the relationship with timber volume, the vegetation indices estimated using hyperspectral data resulted in models with higher r2 when considering the topographic illumination effect, showing higher applicability potential of this data.
Regiane Abjaud Estopa,Magno Antonio Patto Ramalho,Gabriel Dehon Sampaio Pe?anha Rezende,Jupiter Israel Muro Abad
CERNE , 2007,
Abstract: Inbred and outbred Eucalyptus clone were assessed aiming to check the possible loss of vigor in the initial germinationphases and growing in nursery and in t field conditions. Offsprings from two commercial clones were assessed as inbreds (C01 andC02) and as hybrids (C01 x C03 and C02 x C03). The work consisted of two phases. The first one was in the nursery, in a completelyrandom design, with 4 treatments and 6 reps, in plots with 30 tubes with only one seed. The second one, in the field, used a randomizedcomplete block design, with 4 treatments and 6 reps, with 18 plants per plots. The percentage of germination, germination speed index,survival and plant height were assessed at 35, 50, 65 and 80 days in the nursery and, in the field, the percentage of survival with 6months and plant height with 2, 4 and 6 months. It was concluded that the germination, survival and the growing of plants resultedfrom inbred were similar to the hybrid, showing that the loss of vigor is not expressive for those characters in initial developmentalphases of Eucalyptus spp.
Cláudia Lopes Selvati de Oliveira Mori,José Tarcísio Lima,Fábio Akira Mori,Paulo Fernando Trugilho
CERNE , 2005,
Abstract: Due to the importance of wood characterization and standardization, this research evaluated the variability of woodcolor inside and among Eucalyptus spp clones, as well as radially and longitudinally inside the trunk through the quantitativecolorimetric color determination of clones of Eucalyptus wood., using CIELAB 1976 system, , through chromatic coordinates L*, a*,b*, C* e h. Eleven clones of natural Eucalyptus clones hybrids, cultivated at the Northwest of Minas Gerais State, were used. Theresults showed that: all colorimetric parameters were statistically different among clones, and among radial position of samples; itwas possible to identify both clones and samples position along the ray, producing wood of different colours, but tending to yellowishand reddish tonalities.
Flutua??o populacional de Rhizoctonia spp. em jardim clonal de Eucalyptus spp
Sanfuentes, Eugenio;Alfenas, Acelino C.;Maffia, Luiz A.;Mafia, Reginaldo G.;
Fitopatologia Brasileira , 2007, DOI: 10.1590/S0100-41582007000200004
Abstract: leaf blight in shoots of clonal hedges and web blight of cuttings for rooting, caused by rhizoctonia species, may be limiting to the production of eucalyptus seedlings by cuttings. despite their importance, there have been few etiological and epidemiological studies of these diseases. to optimize disease management strategies, this research aimed to evaluate population dynamics of rhizoctonia spp. in soil and eucalyptus cuttings to correlate with disease incidence, and to determine spatial distribution of rhizoctonia spp. inoculum in a clonal nursery of eucalyptus cuttings. population fluctuation of rhizoctonia spp. was detected throughout the year. pathogen distribution in soil was found to have an aggregated pattern. temperature, but not rainfall, was correlated to population levels of rhizoctonia spp in soil samples.
Brazilian Journal of Chemical Engineering , 1998, DOI: 10.1590/S0104-66321998000400007
Abstract: a mathematical model of a process for drying of eucalyptus spp is presented. this model was based on fundamental heat and mass transfer equations and it was numerically solved using a segregated finite volume method. software in the fortran language was developed to solve the mathematical model. the kinetic parameters of drying for eucalyptus spp were experimentally obtained by isothermal thermogravimetry (tg). the theoretical results generated using the mathematical model were validated by experimental data.
Brazilian Journal of Chemical Engineering , 1998,
Abstract: A mathematical model of a process for drying of Eucalyptus spp is presented. This model was based on fundamental heat and mass transfer equations and it was numerically solved using a segregated finite volume method. Software in the FORTRAN language was developed to solve the mathematical model. The kinetic parameters of drying for Eucalyptus spp were experimentally obtained by isothermal thermogravimetry (TG). The theoretical results generated using the mathematical model were validated by experimental data.
Paulo Fernando Trugilho,Fábio Akira Mori,José Tarcísio Lima,Dione Pereira Cardoso
CERNE , 2003,
Abstract: The objective of this study was to determine the tannin contents in the bark oftwenty-five species of Eucalyptus through two extraction methods, one using hot water andthe other a sequence of toluene and ethanol. The results showed that the extraction methodspresented significant differences in the tannin contents. The method using the sequencetoluene and ethanol, for most of the species, promoted a larger extraction of tannin. The hotwater method presented higher contents of tannin for Eucalyptus cloeziana (40,31%),Eucalyptus melanophoia (20,49%) and Eucalyptus paniculata (16,03%). In the toluene andethanol method the species with higher tannin content was Eucalyptus cloeziana (31,00%),Eucalyptus tereticornis (22,83%) and Eucalyptus paniculata (17,64%). The Eucalyptuscloeziana presented great potential as commercial source of tannin, independent of theextraction method considered.
Caracterización fitosanitaria de astillas de Eucalyptus spp. y de especies nativas Phytosanitary characterization of Eucalyptus spp. and native species chips  [cached]
Bosque (Valdivia) , 2003,
Abstract: Se entregan los primeros antecedentes sobre el estado sanitario de astillas de Eucalyptus globulus, E. nitens y de especies nativas. Se estudiaron ocho embarques de astillas, en los cuales el principal problema debido principalmente al tiempo de acanchado del producto fue la presencia de hongos manchadores pertenecientes al género Ceratocystis. No existen problemas ocasionados por insectos, sólo se detectó la presencia de galerías, en un porcentaje muy bajo de astillas de especies nativas (0,05-0,43%), no detectándose problemas en astillas de Eucalyptus spp. This study lists and discusses the occurrence of insects and fungi in eucalyptus (Eucalyptus globulus and E. nitens) chips, as well as on chips from native forest species, for export from Chilean ports. Eight shipments were inspected and analyzed. The main problem was the establishment of Ceratocystis spp. fungi during chip storage. Although no insect species were found, empty galleries were present in the native hardwoods, albeit at very low frequencies (0.05-0.43%). There were no detectable problems with Eucalyptus chips.
Identification and characterization of homeobox genes in Eucalyptus
Rocha, Gra?a Celeste Gomes;Corrêa, Régis Lopes;Borges, Anna Cristina Neves;Sá, Claudio Bustamante Pereira de;Alves-Ferreira, Márcio;
Genetics and Molecular Biology , 2005, DOI: 10.1590/S1415-47572005000400005
Abstract: homeobox genes encode transcriptional factors, usually involved in molecular control of plant developmental patterns. they can be divided into several classes according to conserved sequences within the homeobox region and the presence of specific additional sequences. based on these conserved sequences, we developed a search procedure to identify possible homeobox genes in the eucalyptus genome sequencing project consortium (forests) database. we were able to identify 50 eucalyptus sequences (est-contigs) containing the homeodomain sequence. phylogenetic analysis was applied to this ests-contigs and 44 of them were found to have similarities with one of three well-known homeobox classes: bell, knox and hd-zip, and their sub-classes. however, no est-contig grouped with the fourth important homeobox class, the phd-finger homeobox. on the other hand, two sequences have showed pronounced similarity to the arabidopsis thaliana wuschel gene, considered an "atypical" homeobox gene. hierarchical clustering analysis of the expression pattern of these putative eucalyptus homeobox genes revealed the presence of ten distinct expression groups. combining phylogenetic analysis and expression patterns for some of the eucalyptus genes revealed interesting aspects about some of the potential homeobox genes, which might lead to a better understanding of the eucalyptus biology and to biotechnological applications.
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