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Artigos Científicos - CALTA

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Acesso aberto (Open Access)
Ethanol and citric acid improve longevity in Gerbera cv. Mistique
(Universidade Federal do Pará, 2019-08) MAIA, Rúbia Kécia Marins; SILVA, Edivan Amaro da; ALVES, Rafael Mateus; MORAIS, Maria Aparecida dos Santos; VIEIRA, Marcos Ribeiro da Silva; SILVA, Luzia Ferreira da; FONSECA, Kelem Silva; SIMÔES, Adriano do Nascimento; SIMÔES, Raquel Ferraz Jardim
Ethanol and citric acid can increase longevity in some cut flowers. However, its use must be extremely careful, with application methods and specific concentrations for each type of cut flower. Thus, the objective was to examine the physico-chemical and physiological changes in Gerbera cv. Mistique cut flowers treated with ethanol (Et) and/or citric acid (CA). Stem were selected and standardized to a length of 35 cm and maintained at 20 ± 2 °C and RH 65 ± 2%, under continuous lighting. The flowers were subjected to two application methods (pulsing for 48 h and maintenance), using different concentrations of Et (4%, 6%, and 8%) and/or CA (100 and 200 mg L-1) and distilled water (control). A visual assessment and analyses of longevity, stem bending, fresh mass, relative water content, electrolyte leakage, and peroxidase and polyphenol oxidase enzyme activities were performed at every two days. The Et (4%) + CA (100 mg L-1) solution provided the greatest longevity, regardless of the application method. These results were the basis for a third experiment, in which the stems were immersed in pulsing solutions of Et (4%) and/or CA (100 mg L-1) and distilled water (control). The Gerbera flowers under Et + CA solution showed lower fresh mass loss and electrolyte leakage, higher relative water content and a slower increase in polyphenol oxidase and peroxidase activities. This allowed for delayed stem bending and better appearance, resulting in greater longevity compared to the other solutions.
Acesso aberto (Open Access)
Hybrid sandwich particleboard made with sugarcane, Pínus taeda thermally treated and malva fibre from Amazon
(Associação Brasileira de Metalurgia e Materiais, 2017-12) SILVA, Márcio Rogério da; PINHEIRO, Roberto Vasconcelos; CHRISTOFORO, André Luis; PANZERA, Tulio Hallak; LAHR, Francisco Antonio Rocco
A multilayer particleboard panels, consisted of sugarcane bagasse reinforced composite as core material and hybrid composites made with Pinus taeda particles and Malva fibres as facing materials, were designed and evaluated in this work. Tukey test was used to identify the effect of the facing material, considering different combinations of Pinus taeda particles and Malva fibres, on the bulk density, thickness swelling, flexural strength, flexural stiffness and X-ray densitometry. A spray-up process was used to spread castor oil based polyurethane resin upon the dispersive phases followed by a hot compaction at 100oC. The particleboards were classified as medium density panels in accordance to the Brazilian, American and Canadian Standards. All treatments reached the minimum strength except for elastic modulus. Tukey test demonstrated the flexural strength and modulus responses for all treatments were statistically similar. Hybrid particleboard consisted of 75% of Pinus taeda wood and 25% of Malva fibres revealed a promising sustainable material for furniture industries, combining strength, low-cost and lower thickness swelling values.
Acesso aberto (Open Access)
Diversidade de presas e predadores (Insecta) em mesohabitats de córregos de Cerrado
(Museu de Ciências Naturais, 2018-12) GIEHL, Núbia França da Silva; RESENDE, Bethânia Oliveira de; SILVA, Karina Dias; NOGUEIRA, Denis Silva; CABETTE, Helena Soares Ramos; ROGES, Paulo F. S. S.
Tropical streams feature high variety of habitats and environmental gradients, which reflect on the greater richness of aquatic insects. In this way, we evaluate if the diversity of aquatic insects of prey and predator categories is influenced by the type of substrates or by longitudinal portions in Cerrado streams. Our hypothesis is that prey and predator diversity will be determined by the type of substrate, assuming that the substrate serves as a source for foraging and / or refuge. In addition, the folhiço substrate will present greater abundance and richness due to the availability of shelter and food provided by this type of substrate. There will be differences in prey and predator composition among substrates, since some species have associations with the substrate type. The portions of the stream will have no effect on the diversity of prey and predator, since in streams of up to third order does not present considerable changes in physical characteristics. The study was carried out in nascent (1st order), intermediate (2nd) and estuary (3rd), in two streams, during dry and rainy periods. Five subsamples of sand, gravel, rocks or boulders were collected, backwaters, rapids and roots (substrate). The substrate influenced all prey and predator responses (abundance, richness and composition), but the environment (longitudinal portions) did not influence the abundance and predator composition. The influence of substrates on the diversity of prey and predators evidences the importance of riparian vegetation as a source of allochthonous material in bedside streams.
Acesso aberto (Open Access)
Natural resistance of seven Amazon woods to xylophagous termite nasutitermes octopilis(banks)
(Universidade Federal do Pará, 2019-04) COSTA, Flávio Nascimento; CARDOSO, Rennan de Paula; MENDES, Clebérton Santos; RODRIGUES, Pablo Ramon Garreto; REIS, Alisson Rodrigo Souza
Some Amazonian woods are considered highly resistant to the attack of microorganisms; however, which ones present the highest resistance is unknown. This study aimed to evaluate the natural resistance of seven woods to xylophagous termite Nasutitermes octopilis through a no-choice feeding assay. The following wood species were assessed: Dinizia excelsa, Manilkara huberi, Dipteryx odorata , Bagassa guianensis, Astronium lecointei, Caryocar villosum, and Hymenolobium petraeum (Ducke). To this end, five timber samples from the middle heart at breast height of each plant with dimensions of 2.54 × 2.54 × 0.64 cm (longitudinal × radial × tangential) were collected from sawmills in the municipality of Altamira, Pará state, Brazil, submitted to termite action under laboratory conditions, and had their mass loss and wear assessed, with five replicates. A. lecointei showed the lowest resistance, whereas C. villosum and D. odorata presented the highest resistance.
Acesso aberto (Open Access)
Correlações entre compostos fenólicos e atividade antioxidante em casca e polpa de variedades de uva de mesa
(Instituto de Tecnologia de Alimentos, 2018) SOUZA, Angela Vacaro de; VIEIRA, Marcos Ribeiro da Silva; PUTTI, Fernando Ferrari
Grapes are considered a major source of phenolic compounds when compared to other vegetables, but the great diversity amongst the cultivars results in fruits with different characteristics of taste and colour, which is certainly associated with the polyphenol content and profile. Skins and pulps of ripe samples of “Itália”, “Brasil”, “Rubi”, “Thompson” and “Niagara Rosada” grapes from the Campinas and Jundiaí regions - SP state - Brazil, were studied with the objective of evaluating the antioxidant activity, enzymatic activities of peroxidase and polyphenoloxidase, phenolic compounds and ascorbic acid. In order to verify correlations between the skins and pulps of the varieties and the characteristics studied, Pearson’s correlation, the generalized distance of Mahalanobis (D2) and finally the grouping of the different responses using the multivariate analysis, were carried out. It was verified that the skins of the grapes analysed had a positive correlation with the phenolic compounds, polyphenoloxidase activity and ascorbic acid content, except for “Niagara Rosada”, showing higher levels for these evaluations. There was no correlation between the antioxidant activity and the other analyzes. This shows that for the majority of the varieties evaluated, the skins are a great source of these compounds
Acesso aberto (Open Access)
Eastern extension of the geographic range of Mico emiliae
(Instituto Nacional de Pesquisas da Amazônia, 2018-09) ANDRADE, Roberto Portella de; MOURTHÉ, Ítalo Martins da Costa; SACCARDI, Victor; HERNÁNDEZ-RUZ, Emil José
The distribution of the callitrichids inhabiting the Tapajós-Xingu interfluvium is still poorly understood, probably because of the limited number of studies in this remote region. Mico emiliae is a callitrichid endemic to Brazil, occurring between the Jamanxim and Teles Pires rivers, and Serra do Cachimbo in the west and Iriri River in the east, in the states of Pará and Mato Grosso. However, its current distribution is still uncertain. After ca. 430-km surveys in Serra do Pardo National Park, we successfully confirmed the occurrence of this species for the first time approximately 180 km east of its previously known eastern limit in Pará. Our records expand the distribution of M. emiliae to the left bank of the Xingu River, increasing the known extent of its occurrence by 83%.
Acesso aberto (Open Access)
Genetic diversity of American wild rice species
(Universidade Federal do Pará, 2011-08) VEASEY, Elizabeth Ann; BRESSAN, Eduardo de Andrade; ZUCCHI, Maria Imaculada; VENCOVSKY, Roland; CARDIM, Daruska Cavalcante; SILVA, Rainério Meireles da
Studies on genetic diversity and genetic structure of natural populations are important in order to define strategies for in situ and ex situ conservation actions and for plant pre-breeding programs. Aiming to assess the genetic diversity and genetic structure of three wild American Oryza species with isozyme markers, 14 populations of the diploid O. glumaepatula (AglAgl), 11 populations of the tetraploid O. grandiglumis (CCDD) and five populations of the also tetraploid O. latifolia (CCDD) were studied. They were all originated from Rio Paraguay hydrographic basin and the Amazon. Four enzymes were used and they gave 40 polymorphic bands. The most polymorphic species was O. glumaepatula, followed by O. latifolia and O. grandiglumis. A cluster analysis with the Jaccard similarity coefficient separated the diploid from the two tetraploid species, and also the two tetraploid species. This separation was also evident on a scatter plot from a principal component analysis, suggesting that they should be treated as two separate species, although further studies are necessary to provide support for this affirmative. The AMOVA analyses showed a high intrapopulational variability for O. latifolia (67.6%) and O. grandiglumis (52.2%), when compared to their interpopulational variability (32.4% and 47.8%, respectively), which suggests the hypothesis of a higher degree of outcrossing events within these species. When studying the correlation between the Jaccard dissimilarity coefficient and geographic distances, a spatial genetic structure was observed for O. glumaepatula only. These results are important for defining strategies of both in situ and ex situ conservation.
Acesso aberto (Open Access)
Elaboração e validação de escala diagramática para avaliação da severidade da ferrugem branca do crisântemo
(Grupo Paulista de Fitopatologia, 2006-03) BARBOSA, Maria Angélica Guimarães; MICHEREFF, Sami Jorge; MORA-AGUILERA, Gustavo
White rust, caused by Puccinia horiana, is considered the major disease of Chrysanthemum in Brazil, which results in severe losses for the growers. Despite of its economic importance, very few epidemiological studies have been carried out in Brazil. In order to conduct these studies it is necessary to develop standard methods to quantify disease severity under field conditions. Therefore, a diagrammatic key, including the levels 1, 3, 6, 10, 18, and 30% of diseased leaf area, was elaborated. The severity of the white rust was estimates using the key or not in order to test its accuracy, precision and reproducibility. The diagrammatic key was validated by 10 raters using 50 leaves with different levels of severity, which were previously measured by the AutoCAD® software. Two evaluations were performed with the key at 7-day intervals when different sequences of the same leaves were visually estimated by the same raters. The accuracy and precision of each rater were determined by using simple linear regression between actual and estimated severity. When the key was not used, all raters overestimated disease severity indicating the presence of constant positive errors for all levels of disease severity. The evaluations using the diagrammatic key were more accurate for the great majority of the raters and more precise for all the raters. In addition, the key also showed good repeatability and high level of reproducibility among the evaluations from the different raters. The diagrammatic key is suitable for the evaluation of severity of white rust of Chrysanthemum.
Acesso aberto (Open Access)
Water seasonality in granting permits and impact of irrigation in the Dourados River basin, MS, Brazil
(Universidade Federal do Pará, 2017-07) RAMOS, Diovany Doffinger; PEREIRA, Sílvio Bueno; ARAI, Fabiane Kazue; SANTOS, Felipe André dos; CARNEVALI, Thiago de Oliveira
The objective of this study was to evaluate water seasonality in the process of granting permits and the impact of irrigation in the Dourados River basin. For that, the hydrological behavior of the basin was analyzed. The minimal streamflows (Q7,10 and Q95), irrigation withdrawal flow (Qr) and the percent variation of the grant flows relative to monthly seasonal period in relation to the monthly withdrawal flow were obtained. The results allowed to verify that using criteria based on the monthly streamflow allows for better management of water use, because it allows for greater utilization of this resource in times with high water availability and imposes a realistic restriction during critical periods. The average annual water withdrawal for irrigation in the basin during the studied period was on the order of 2.99 m3 s-1, and the withdrawal flow in the month of highest demand (August) was 5.95 m3 s-1.
Acesso aberto (Open Access)
Cytogenetic analysis of Baryancistrus xanthellus (Siluriformes: Loricariidae: Ancistrini), an ornamental fish endemic to the Xingu River, Brazil
(Sociedade Brasileira de Ictiologia, 2016) MEDEIROS, Larissa Azevedo de; GURGEL, Eduardo Gentil Ginani; SOUSA, Leandro Melo de; PY-DANIEL, Lúcia Helena Rapp; FELDBERG, Eliana
Baryancistrus xanthellus is a species from the Ancistrini tribe known commonly as "amarelinho " or "golden nugget pleco". It is one of the most popular and valued ornamental fishes due to its color pattern. Also, it is an endemic species from the Xingu River occurring from Volta Grande do Xingu, region where the Belo Monte Hydropower Dam is being built, to São Félix do Xingu. The current study aimed to cytogenetically characterize B. xanthellus . Results point to the maintenance of 2n=52, which is considered the most common condition for the tribe, and a single nucleolus organizer region (NOR). Mapping of the 18S rDNA confirmed the NOR sites, and the 5S rDNA was mapped in the interstitial position of a single chromosome pair. The 18S and 5S rDNA located in different pairs constitute an apomorphy in Loricariidae. Large blocks of heterochromatin are present in pairs 1 and 10 and in the regions equivalent to NOR and the 5S rDNA. Data obtained in this study corroborated with the currently accepted phylogenetic hypothesis for the Ancistrini and demonstrate evidence that the genus Baryancistrus occupies a basal position in the tribe.
Acesso aberto (Open Access)
Morphological aspects of fruits, seeds, and seedlings, and anatomy of seedlings of apuleia molaris spruce ex benth
(Associação Brasileira de Tecnologia de Sementes, 2016-06) REIS, Alisson Rodrigo Souza; FREITAS, Alessandra Doce Dias de; LEÃO, Noemi Vianna Martins; SANTOS FILHO, Benedito Gomes dos
Apuleia molaris spruce ex benth, commonly known in Brazil as "amarelão," is a fast-growing forest plant with a potential for use in reforestation; however, there is little information about the physiology and morphology of its fruits, seeds, and seedlings. Thus, the objective of this work was to describe the morphology of the fruits, seeds, and seedlings, in addition to the anatomic patterns of seedlings, as a contribution to the technical-scientific knowledge and production of amazonian species for reforestation in the state of Pará. For this purpose, the morphological descriptions followed the parameters from specialized literature and the common techniques used in plant anatomy. The species presents leguminous fruit; seeds with pleurogram, average dimensions of 51.21, 21.33, and 2.09 mm length, width, and thickness, respectively; and seedlings with eophyll and pinnate metaphylls, cordiform, phanerocotylar germination, epigaeous, and foliaceous. Eophylls and metaphylls present uniseriate epidermis, collateral and dorsiventral vascular bundle. The morphological characteristics may help in field identification and in the identification of young plants, aiding the production of seedlings of this species. Furthermore, anatomically, the hypocotyl has no striking differences from the root.
Acesso aberto (Open Access)
O papel do Programa Bolsa Família na segurança alimentar das famílias do Território do Marajó, PA
(Universidade Federal do Pará, 2017-06) NASCIMENTO, Elcio Costa do; CARVALHO, João Paulo Leão de; CRUZ, Benedito Ely Valente da; CALVI, Miqueias Freitas
This paper aims to analyze the role that Programa Bolsa Família plays in the food security of the families in the Marajó Territory, located in the State of Pará, Brazil. Using a qualitative approach, we sought an understanding of the benefit of the program's influence in food, economic and social practices. A positive impact was observed in access to food and standard of living, providing well-being, better quality of life and development of credit practices, necessary to combat food insecurity in the region.
Acesso aberto (Open Access)
Methylmercury inhibits prolactin release in a cell line of pituitary origin
(Universidade Federal do Pará, 2015-08) MAUÉS, Luis Antônio Loureiro; MACCHI, Barbarella de Matos; CRESPO LÓPEZ, Maria Elena; NASCIUTTI, Luís Eurico; DINIZ, Domingos Luiz Wanderley Picanço
Heavy metals, such as methylmercury, are key environmental pollutants that easily reach human beings by bioaccumulation through the food chain. Several reports have demonstrated that endocrine organs, and especially the pituitary gland, are potential targets for mercury accumulation; however, the effects on the regulation of hormonal release are unclear. It has been suggested that serum prolactin could represent a biomarker of heavy metal exposure. The aim of this study was to evaluate the effect of methylmercury on prolactin release and the role of the nitrergic system using prolactin secretory cells (the mammosomatotroph cell line, GH3B6). Exposure to methylmercury (0-100 μM) was cytotoxic in a time- and concentration-dependent manner, with an LC50 higher than described for cells of neuronal origin, suggesting GH3B6 cells have a relative resistance. Methylmercury (at exposures as low as 1 μM for 2 h) also decreased prolactin release. Interestingly, inhibition of nitric oxide synthase by N-nitro-L-arginine completely prevented the decrease in prolactin release without acute neurotoxic effects of methylmercury. These data indicate that the decrease in prolactin production occurs via activation of the nitrergic system and is an early effect of methylmercury in cells of pituitary origin.
Acesso aberto (Open Access)
Effect of waterfalls and the flood pulse on the structure of fish assemblages of the middle Xingu River in the eastern Amazon basin
(Instituto Internacional de Ecologia, 2015-08) BARBOSA, Thiago Augusto Pedroso; BENONE, Naraiana Loureiro; RUFFEIL, Tiago Octavio Begot; GONÇALVES, Alany Pedrosa; SOUSA, Leandro Melo de; GIARRIZZO, Tommaso; JUEN, Leandro; MONTAG, Luciano Fogaça de Assis
The structure of fish assemblages in Neotropical rivers is influenced by a series of environmental, spatial and/or temporal factors, given that different species will occupy the habitats that present the most favourable conditions to their survival. The present study aims to identify the principal factors responsible for the structuring of the fish assemblages found in the middle Xingu River, examining the influence of environmental, spatial, and temporal factors, in addition to the presence of natural barriers (waterfalls). For this, data were collected every three months between July 2012 and April 2013, using gillnets of different sizes and meshes. In addition to biotic data, 17 environmental variables were measured. A total of 8,485 fish specimens were collected during the study, representing 188 species. Total dissolved solids, conductivity, total suspended matter, and dissolved oxygen concentrations were the variables that had the greatest influence on the characteristics of the fish fauna of the middle Xingu. Only the barriers and hydrological periods played a significant deterministic role, resulting in both longitudinal and lateral gradients. This emphasizes the role of the connectivity of the different habitats found within the study area in the structuring of its fish assemblages.
Acesso aberto (Open Access)
Genetic parameters and simultaneous selection for root yield, adaptability and stability of cassava genotypes
(Empresa Brasileira de Pesquisa Agropecuária, 2013-12) FARIAS NETO, João Tomé de; CUNHA, Elisa Ferreira Moura; RESENDE, Marcos Deon Vilela de; CELESTINO FILHO, Pedro; AUGUSTO, Sebastião Geraldo
The objective of this work was to estimate genetic parameters and to evaluate simultaneous selection for root yield and for adaptability and stability of cassava genotypes. The effects of genotypes were assumed as fixed and random, and the mixed model methodology (REML/Blup) was used to estimate genetic parameters and the harmonic mean of the relative performance of genotypic values (HMRPGV), for simultaneous selection purposes. Ten genotypes were analyzed in a complete randomized block design, with four replicates. The experiment was carried out in the municipalities of Altamira, Santarém, and Santa Luzia do Pará in the state of Pará, Brazil, in the growing seasons of 2009/2010, 2010/2011, and 2011/2012. Roots were harvested 12 months after planting, in all tested locations. Root yield had low coefficients of genotypic variation (4.25%) and broad-sense heritability of individual plots (0.0424), which resulted in low genetic gain. Due to the low genotypic correlation (0.15), genotype classification as to root yield varied according to the environment. Genotypes CPATU 060, CPATU 229, and CPATU 404 stood out as to their yield, adaptability, and stability.
Acesso aberto (Open Access)
Diversidade genética molecular de progênies de dendezeiro
(2012-03) FERREIRA, Crystianne Bentes Barbosa; LOPES, Maria Teresa Gomes; LOPES, Ricardo; CUNHA, Raimundo Nonato Vieira da; MOREIRA, Djair Alves; BARROS, Willian Silva; MATIELLO, Rodrigo Rodrigues
The objective of this work was to assess the genetic diversity between and within progenies of dura type oil palm from Deli. Genetic characterization was performed with microsatellite markers on 24 oil palm progenies used in commercial seed production, of which 22 originated from self-fertilization and two from cross-fertilization between full siblings. Molecular analysis of variance was carried out among and within progenies, and a dendrogram was constructed. Low genetic variability was observed within progenies, with an average of 1.32 alleles per locus and total variance of 0.3241. Most of the variation was found between progenies. The lower genetic variability within progenies can be explored in crossings with endogamic progenies from other origins, which would facilitate heterosis in order to develop new varieties.
Acesso aberto (Open Access)
Decontaminant solution on in vitro growth of Byrsonima intermedia seedlings
(2015-04) SILVA, Luciano Coutinho; PAIVA, Renato; VARGAS, Daiane Peixoto; SILVA, Diogo Pedrosa Corrêa da; BARBOSA, Sandro; HERRERA, Raírys Cravo
Byrsonima intermedia A. Juss., is a medicinal and fruit plant of the Cerrado in which the conventional propagation is difficult due to the presence of extremely lignified endocarps. Although sodium hypochlorite (NaOCl) is widely used in the surface decontamination, there are few reports of its effects on explant growth. The aim of this work was to study the effect of different pH and exposure periods of B. intermedia seeds to a NaOCl solution. Seeds were subjected to different exposure periods (1, 5 and 10 minutes) to a NaOCl solution at different pH (5, 7, 10 and 12) and after treatment with NaOCl, embryos were inoculated in a WPM medium with 50% concentration of salts without sucrose, 0.5% agar and pH 5.8 and after 75 days of culture the growth of seedlings was evaluated. The use of NaOCl is effective in the decontamination of B. intermedia seeds, independent of pH variation and exposure periods and the parameters such as percentage of normal seedlings, shoot length, and number of leaves are positively affected by the use of NaOCl solution at pH 8.5-8.9 and by increasing the exposure period, however, the number of roots is affected only by increasing the exposure period in the NaOCl solution.
Acesso aberto (Open Access)
Sperm depletion: a cost for single mated females of Podisus nigrispinus (Dallas, 1851) (Heteroptera: Pentatomidae)
(2006-11) SOUTO, Leandro Sousa; EVANGELISTA JÚNIOR, Walter Santos; LIMA, Eraldo Rodrigues; ZANUNCIO, José Cola; FONSECA, Marcy das Graças
The aim of this work was to test if egg viability of polyandrous females was increased with increasing number of matings. Longevity and reproductive output of females of the predatory stinkbug Podisus nigrispinus that were allowed to mate for 0, 1, 2, 3 times or were in the continuous presence of the same male was evaluated. Polyandry resulted in diminished sperm depletion. Females that had mated three times or that were in continuous presence of a male produced more offspring than females that mated once or twice throughout their lifetime. There was a negative correlation of mating history on female longevity. Results indicated that remating, either with same male or with different males were crucial for maximization of the reproductive success of females.
Acesso aberto (Open Access)
Assessing the genetic structure of Oryza glumaepatula populations with isozyme markers
(2008-10) VEASEY, Elizabeth Ann; CARDIM, Daruska Cavalcante; SILVA, Rainério Meireles da; BRESSAN, Eduardo de Andrade; VENCOVSKY, Roland
To assess the genetic diversity and genetic structure parameters, nine populations of Oryza glumaepatula from the Amazon biome, four from the Pantanal biome, and one collected at Rio Xingu, Mato Grosso, totaling 14 populations and 333 individuals were studied with isozyme markers. Six loci were evaluated showing a moderate allozyme variability (A = 1.21, P = 20.7%, Ho = 0.005, He = 0.060). The populations from the Pantanal biome showed higher diversity levels than the Amazon biome. High genetic differentiation among the populations, expected for self-fertilizing species, was observed (FST=0.763), with lower differentiation found among the Pantanal populations (FST=0.501). The average apparent outcrossing rate was higher for the Pantanal populations (ta = 0.092) than for the Amazonian populations (ta = 0.003), while the average for the 14 populations was 0.047, in accordance with a self-fertilization mating system.
Acesso aberto (Open Access)
Micropropagation of Maclura tinctoria L.: an endangered woody species
(2010-02) GOMES, Guilherme Augusto Canella; PAIVA, Renato; HERRERA, Raírys Cravo; PAIVA, Patrícia Duarte de Oliveira
Some native species produce seeds with low germination percentage and in most cases with dormancy, which makes the appearance of new individuals by sexual propagation difficult. The Maclura tinctoria has been considered an endangered species due to the indiscriminate use of its wood and low rate of seed germination. In this context, the objective of the present study was to establish an in vitropropagation methodology for this species. Combinations of NAA + BAP, different concentrations of GA3 and combinations IBA + activated charcoal were evaluated for shoot induction, shoot growth and root formation, respectively. The results indicated that the maximum shoot formation was obtained when 5.37 µM NAA + 4.45 µM BAP was used. The use of >5.48 µM GA3 promoted shoot growth. Root formation was observed on explants inoculated in WPM with a pH adjusted to 7.0 and supplemented with 23.62 µM IBA + 4.7 g L-1 activated charcoal. The use of a 70% light screen for 7 days followed by the use of 50 and 30% light screens also for 7 days each provided 97% plantlet survival.