Tetrazolium Test Results Research Articles

Effect of Different Presowing Treatments to Break Seed Dormancy and Seed Collection Methods on the Germination of Dracaena steudneri Schweinf. Ex Engl.

Research Highlights: This study is focused on the germination of Dracaena steudneri Schweinf. Ex Engl. seeds using different presowing treatments. Background and Objectives: The study aimed to overcome the problem of breaking seed dormancy, to facilitate artificial regeneration for conservation and development purposes. The objectives of this study were (1) to evaluate the effect of different seed treatments in breaking seed dormancy of D. steudneri and (2) to assess the effect of the seed collection method (seeds collected on the ground vs. from the tree) on the germination of the seed. Materials and Methods: experimental study with different seed-dormancy-breaking treatments was carried out in a greenhouse and seed laboratory. T testing and one way analysis of variance (ANOVA) were used to analyse the data. Results: The applied seed treatments (hot water, cold water, sodium hypochlorite and nicking) did not improve the germination of the species, nor the breaking of seed dormancy. One-way ANOVA results also showed no significant differences between the different seed treatments and the control on the mean germination of the species in the greenhouse (p < 0.05). The t test result also revealed no significant differences in the mean germination between fallen seeds collected from the ground and in the tree crown (p < 0.05). The tetrazolium test results showed that the percentage of nonviable seeds was greater than that of the viable seeds. Conclusion: The different treatments for breaking seed dormancy did not improve the germination of seeds in the greenhouse (ranging from 0%–7%) nor in the seed laboratory (0%), which might be due to the intermediate characteristics of the seeds of this species. Therefore, we recommend that more research is undertaken on the seed ecophysiology of the species, in order to understand the mechanisms controlling its seed germination.

Suitability of tetrazolium test for Tamarindus indica L. seeds

Seed quality is routinely assessed by direct tests, e.g, the germination test, or indirect tests like the tetrazolium test, which has shoown to be promising in the determine viability and vigor, allowing the diagnosis of the main problems that may affect seed quality, such as mechanic damages, field deterioration and storage. In this respect, this study was conducted to develop a tetrazolium test protocol to evaluate the viability and vigor of Tamarindus indica L. seeds. Before exposing the seeds to the tetrazolium solution, seed preconditioning studies were carried out in which seven soaking times were tested. The soaking time that did not cause damage to the seed embryo and allowed the removal of the seed coat to expose the seed structures to the tetrazolium salt was selected. Then, an experiment was set up in a completely randomized design with a 2x3x3 factorial arrangement involving two seed lots, three soaking times in tetrazolium salt (6, 12 and 16 h) and three salt concentrations (0.075, 0.1 and 0.5%), totaling 18 treatments with four replicates of 25 seeds, evaluated at 40 ºC. For each treatment, the seeds were divided into three classes, namely, viable and vigorous embryos (class 1); viable embryos (class 2) and non-viable or dead embryos (class 3). For a comparison with the tetrazolium test results, the two seed lots were analyzed for water content, germination, emergence, first count, germination speed index, emergence speed index, growth and seedling dry weight. The viability and vigor of T. indica seeds can be evaluated after a soaking period of 48 h and immersion for 6h in tetrazolium salt at the concentration of 0.1%, at 40°C, with provides results similar to conventional seed viability tests. The tetrazolium test proved to be adequate to differentiate T. indica seed lots in terms of viability.

EVALUATION OF VIABILITY OF Tabebuia aurea SEEDS THROUGH TETRAZOLIUM TEST

ABSTRACT The viability of T. aurea seeds is evaluated through the germination test, taking 21 days, which makes it difficult to obtain quick information about the viability of its seeds. In this context, using the tetrazolium test as an evaluation method would be appropriate because it provides faster and more reliable information for several species. In view of the above, the objective of this study was to adapt the tetrazolium test methodology to evaluate the viability of T. aurea seeds. Initially, the imbibition curve was constructed to determine the appropriate hydration period for the seeds and the germination test was conducted, both for evaluating the initial quality and for comparison with the tetrazolium test results. For the tetrazolium test, the seeds were hydrated for 24 hours, then their coats were removed and the seeds were immersed in tetrazolium solutions. The concentrations used were 0.05, 0.075 and 0.1% for three staining periods 2, 4 and 6 hours, at 35 and 40 °C, in the absence of light. The experimental design was completely randomized in a 3 x 3 + 1 factorial scheme (three concentrations of tetrazolium solution x three staining periods + one control = germination test) with four replicates of 25 seeds. Tetrazolium test was adequate to evaluate the viability of T. aurea seeds using the concentration of 0.05% for four hours at 40 °C.

Imagens digitalizadas na avaliação do teste de tetrazólio em sementes de trigo

The tetrazolium test can be an alternative to obtain fast results of the physiological potential of wheat seeds. In this context, the objective of the present study was to evaluate the efficiency of the tetrazolium test through the evaluation by analysis of digitized images in the determination of the physiological quality of wheat seeds.The experiment was carried out with 22 lots of wheat seeds, submitted to the determination of the physiological potential, including the tetrazolium test evaluated by means of digitized image analysis.For digitization, after longitudinal bisection, and staining in 0.075% tetrazolium solution, the seeds were grouped on tabletop scanner glass, stored and classified into four vigor classes. Data were submitted to analysis of variance, with means grouped by the Scott-Knott test, at 5% of significance; we also performed an analysis of the simple correlation coefficients between tetrazolium test results and other tests.The evaluation of the tetrazolium test through the analysis of digitized images grouped the lots in three levels of vigor.The method is effective in determining the vigor and viability of wheat seeds, because the possibility of expanding the images that allows precise analysis of the embryonic axis structures.

Identification of physiological analysis parameters associated with coffee beverage quality

ABSTRACT The demand for high-quality coffee among consumers has generated a great deal of interest among producers in serving this market. Parameters for physiological analyses that can be associated with aspects of sensory analyses of coffee can ensure more reliable results for coffee quality assessments. The aim of this study was to investigate the potential of physiological analyses in determining coffee quality through multivariate analysis. Several samples from coffee bean/seed lots were placed in cold storage at 10 °C, after which the sensory quality, physiological quality, and chemical characteristics of the beans were evaluated before storage and after three and six months of storage. The variables of physiological quality in the coffee beans were correlated with sensory analysis parameters. The viability of coffee embryos revealed by the tetrazolium test results were positively correlated with the final sensory analysis score. There was a correlation of root dry matter, hypocotyl dry matter, potassium leaching, and electrical conductivity with the sensory attributes that comprise the final sensory analysis score for the coffee beans. Variation in the final sensory analysis score was explained up to 97.14% by the variables radical emergence (r2 = 2.27%), strong normal seedlings, (r2 = 0.56%), seedlings with expanded cotyledonary leaves (r2 = 0.53%), tetrazolium test results (r2 = 91.54%), and potassium leaching (r2 = 2.24%). More studies are required to enable the use of physiological analyses to complement sensory analysis.

Viability of embryonic axes of Araucaria angustifolia after freezing using two cryopreservation methods

Araucaria angustifolia (Bertol.) O. Kuntze é uma das espécies nativas do Brasil com maior importância na Região Sul. No entanto, suas sementes são recalcitrantes, constituindo um obstáculo para a sua conservação em longo prazo, sendo a criopreservação uma alternativa viável para o armazenamento de seu germoplasma. Os eixos embrionários (EE) excisados das sementes de araucária foram encapsulados, desidratados e submetidos a dois métodos de criopreservação: o resfriamento rápido, congelando em nitrogênio líquido (NL) durante 2 h, e o pré-resfriamento a - 40 °C, seguido do congelamento em nitrogênio líquido durante 2 h. Posteriormente, os EE foram descongelados rapidamente e avaliados quanto à integridade do DNA pelo teste bioquímico do tetrazólio, germinação in vitro e ocorrência de oxidação. Tanto o DNA dos EE que não foram criopreservados quanto o daqueles que foram criopreservados mantiveram sua integridade. Os resultados do teste de tetrazólio indicaram que a maioria dos EE desidratados pelo congelamento rápido permaneceu viável. Após 15 dias de cultivo in vitro, os EE não germinaram e apresentaram sinais de oxidação. Os métodos de encapsulamento-desidratação seguidos de congelamento rápido são promissores para a criopreservação de EE de araucária, como demonstrado pelo teste de tetrazólio e da manutenção da integridade total do DNA.

Can the Tetrazolium Test be Used as an Alternative to the Germination Test in Determining Seed Viability of Grass Species?

Currently, the standard germination test (SGT) is the official test for evaluating seed viability in seed testing laboratories around the world. The SGT takes 3 to 4 wk to complete for most grasses, including the dormancy breaking treatment period. The tetrazolium test (TZT), however, offers quick viability determination within 24 to 48 h, even for dormant seeds. This study was conducted to compare SGT and TZT results for tall fescue (TF), annual and perennial ryegrass (ARG and PRG), orchardgrass (OG), bentgrass (BG), Kentucky bluegrass (KBG), and fine fescues (FF). A total of 3432 samples representing the seven species were evaluated for viability by SGT and TZT during 2009 to 2013 at the Oregon State University Seed Laboratory (OSUSL). According to the germination tolerance table of the Association of Official Seed Analysts (AOSA), both SGT and TZT results were within tolerance in 94.2% of TF samples, 95.2% of ARG samples, 90.4% of PRG samples, 93.7% of OG samples, 90.8% of FF samples, 83.9% of BG samples, and 42.4% of KBG samples. Dormancy was the main reason for higher viability by TZT results than by SGT in the same sample, causing the two test results to be out‐of‐tolerance. Based on these results, it can be concluded that the TZT can be used as an alternative viability test to the SGT for TF, ARG, PRG, OG, FF, and possibly for BG. However, the KBG has higher levels of dormancy, which brings the SGT below the TZT results, especially for freshly harvested seeds.

Tetrazolium test for viability estimation of Eugenia involucrata DC. and Eugenia pyriformis Cambess. seeds

The study aimed to adapt the tetrazolium test methodology to assess the viability of seed of Eugenia involucrata DC. (cherry) and E. pyriformis Cambess. (uvaia) freshly harvested and stored. Three lots of seeds of both species were used, being I (freshly harvested), II (stored for 15 days) and III (stored for 30 days). Seeds (lot I) of both species were immersed in distilled water for 24 hours and submitted to four preparation methods: whole seeds without seed coat and with ¾ of seed coat; longitudinally cut with and without seed coat (immersed in 0.1% tetrazolium for 4 hours). The most suitable preparation method was applied to the remaining lots, where three tetrazolium concentrations were tested: 0.075, 0.1 and 0.5% and three immersion time periods: 2, 4 and 6 hours. The tetrazolium test results were compared to the germination results. For the conduction of the tetrazolium test in seeds of both species we recommend soaking in distilled water by 24 hours and cut lengthwise on seeds with the seed coat. For cherry, the seeds should be immersed in 0.5% tetrazolium solution for 2 hours. For uvaia seeds, additional studies are recommended.

Improved assessment of viability and germination of Cattleya (Orchidaceae) seeds following storage

Effective seed storage methods for orchid species provide a unique opportunity to preserve large amounts of germplasm. Early evaluation of the physiological status of seeds is useful for selecting seed lots for conservation. To score seed quality, seeds from nine Cattleya species (Cattleya granulosa, Cattleya hegeriana, Cattleya intermedia, Cattleya mossiae, Cattleya purpurata, Cattleya sanguiloba, Cattleya tenuis, Cattleya tigrina and Cattleya walkeriana) were germinated on Knudson C medium and viability was measured using a tetrazolium (TZ) test following pre-conditioning in a 10% sucrose solution, both before and after storage at −18°C for 3 mo. Tetrazolium test results were quantified using digital imaging of germinating seeds on a flatbed scanner. Seed viability (with or without pre-conditioning in sucrose), germination, Germination Velocity Index (GVI) and the correlation between viability measurements and germination were also evaluated. Both the tetrazolium test and the germination results showed that there was no loss of viability after storage, although in five seed lots, the GVI decreased. Pre-conditioning improved the correlation between viability exhibited in the tetrazolium test and seed germination. Image analysis proved to be a powerful tool for analysing these small seeds.

Dedifferentiation of differentiated thyroid carcinoma cell line FTC-133 is enhanced by 131I pretreatment

Differentiated thyroid carcinoma (DTC) usually has a high iodine uptake. However, dedifferentiation of DTC with decreased or no radioiodine ((131)I) uptake is observed in clinical practice, with poor prognosis. The aim of this study was to investigate the effects of (131)I radiation on radioiodine uptake (RAIU) and the expression of thyroid-specific molecules. FTC-133 cells were treated with (131)I, the dosage dictated by methylthiazol tetrazolium test results and preliminary experiments. The experimental cell group was incubated with (131)I for 48 h and then cultured for 3 months in (131)I-free medium. The control group was set without (131)I. Primary cells were defined as the blank group. Following treatment, RAIU was measured with a gamma counter as the counts/cell number. Na(+)/I(-) symporter (NIS), thyroid-stimulating hormone receptor (TSHR), thyroid peroxidase (TPO) and thyroglobulin (Tg) levels were detected by Western blotting and radioimmunoassay, and their mRNAs were detected by real-time polymerase chain reaction. RAIU of FTC-133 cells decreased gradually after coincubation with (131)I and did not recover even if (131)I was removed. The relative RAIU of the control and experimental groups was 0.567 and 0.182, respectively, a statistically significant difference (P<.01). Expression of NIS, TSHR, TPO and Tg decreased in the experimental group to a statistically significant degree compared to that of controls (P<.05). Changes in the mRNA levels were in accordance with the expression of thyroid-specific proteins. Thus, FTC-133 cells undergo dedifferentiation during long-term culture in vitro, and (131)I may promote this progress.

Avaliação da viabilidade de sementes de coração-de-negro (Poecilanthe parviflora Benth. - Fabaceae-faboideae) pelo teste de tetrazólio

A crescente demanda por sementes de espécies arbóreas brasileiras tem sido acompanhada pelo aumento da necessidade em se desenvolver métodos para a avaliação da viabilidade das sementes, principalmente por meio de testes rápidos, como o de tetrazólio. Poecilanthe parviflora (coração-de-negro) é uma espécie arbórea brasileira utilizada na restauração florestal, para a qual não há testes estabelecidos para a determinação da viabilidade de suas sementes. Assim, a pesquisa objetivou adequar o método do teste de tetrazólio para a avaliação da viabilidade de sementes da referida espécie. A partir de estudos preliminares, relacionados à hidratação, ao preparo e à coloração das sementes, as sementes foram hidratadas pela imersão direta em água, até atingirem 30% e 40%, e entre papel previamente umedecido com água, até atingirem 40%. Após a hidratação, o tegumento das sementes foi retirado manualmente e os embriões foram imersos em solução 0,075% de tetrazólio por 90 minutos a 40°C. Os resultados do teste de germinação foram empregados como referência para os de tetrazólio. É possível utilizar o teste de tetrazólio para avaliar a viabilidade das sementes de coração-de-negro. É recomendada a imersão das sementes em água, até atingirem 40%, a remoção do tegumento e a coloração do embrião em solução 0,075% de tetrazólio, durante 90 minutos, no escuro, a 40ºC.

Newly diagnosed chronic granulomatous disease in a 53-year-old woman with Crohn disease

Chronic granulomatous disease (CGD) is characterized by defective bactericidal activity of white blood cells, specifically, a defect in superoxide production. Patients experience infections, predominantly caused by catalase-positive bacteria and fungal organisms, that may be severe and life-threatening. Most cases of CGD are diagnosed in children; however, it may rarely go undiagnosed until adulthood in individuals with unexplained infections and granulomatous inflammation. To describe an adult with Crohn disease and recurrent infections who was newly diagnosed as having CGD. A 53-year-old woman with a history of liver abscesses and Crohn disease presented with Burkholderia cepacia pneumonia and required a right middle lobe resection. Nitroblue tetrazolium test results confirmed the diagnosis of CGD, and Western blot analysis revealed the absence of the 47-phagocyte oxidase protein. Levels of Crohn-associated specific antibodies to Saccharomyces cerevisiae and Escherichia coli outer membrane porin C were elevated. The patient, newly diagnosed as having CGD, was given intravenous trimethoprim-sulfamethoxazole, after which she improved clinically and was discharged from the hospital in stable condition to receive daily oral trimethoprim-sulfamethoxazole treatment. The concomitant occurrence of Crohn disease and CGD, both characterized by granulomatous inflammation, is noteworthy. This case study demonstrates that CGD should be considered in adults with recurrent infections, especially those caused by catalase-positive organisms, such as B cepacia.

Chronic granulomatous disease: quantitative clinicopathological relationships.

10 children with chronic granulomatous disease are described. Though the clinical features were typical, a wide range of clinical severity was noted. A significant correlation between the severity of the syndrome and the qualitative nitro-blue tetrazolium results was found. Facial rashes (4) and polyarthritis (1) were noted in female presumed heterozygotes, the incidence of which was also related to the nitro-blue tetrazolium test results. A father and a paternal great uncle died of leukaemia. The possible aetiological relation between these and the partial leucocyte abnormality is discussed. Three children were treated with busulphan, in order to induce neutropenia, to expose the ingested organisms to humoral bactericidal mechanisms, and to antibiotics. There was evidence suggestive of benefit in one of them.