Embryogenic potential of the callus of gabirobeira, Campomanesia adamantium(Cambess) O. Berg

Campomanesia adamantiumis a native plant species of Brazilian Cerrado with diverse economic potential and great medicinal importance. Its sexual propagation is impaired by the recalcitrance of its seeds, which prevents effective and profitable propagation. With the purpose of establishing commercial crops and minimizing the extractive use of vegetal resources, the aim of the present study was to induce embryogenic calli in nodal segments of gabirobeira, and to determine and characterize their embryogenic phase through the establishment of a growth curve based on cellular characteristics. Calli were induced using nodal segments inoculated in WPM culture medium without the addition of hormones (control) and with different concentrations of 2,4-D, IAA, IBA, NAA or picloram. Cytochemical and SEM analyses revealed cellular characteristics of the formation of meristematic centers that indicated 4.14 μM of picloram to be the best treatment for induction of embryogenic calli, and demonstrating their embryogenic potential. The treatment was used to establish a callus growth curve, from which it was inferred that calli should be transferred to new culture media on the 28thday to maintain cell viability.

In vitro efficacy of latex and purified papain from Carica papaya against Strongyloides venezuelensis eggs and larvae

ABSTRACT Latex from Carica papaya is rich in bioactive compounds, especially papain, which may help to control parasitic diseases. This study evaluated the efficacy of latex from C. papaya and purified papain against Strongyloides venezuelensis. The Egg Hatching Test (EHT) and the Larval Motility Test (LMT) using fresh and frozen latex (250mg/mL), lyophilized latex (34mg/mL), and purified papain (2.8 mg/mL) were performed. Albendazole (0.025 mg/mL) and ivermectin (316 ppm) were used as positive controls. EHT and LMT were carried out through the incubation of each solution with S. venezuelensis eggs or larvae (± 100 specimens), and results were analyzed after 48h (EHT) or 24, 48, and 72h (LMT). EHT showed that latex preparations at higher concentrations (1:10 to 1:100) resulted in partial or complete destruction of eggs and larvae inside the eggs. The result from the 1:1,000 dilution was similar to the positive control. LMT showed effectiveness in all the tested dilutions compared to negative controls. Purified papain showed a dose-dependent response in the EHT. Purified papain (2.8 mg/ mL) showed similar results to lyophilized latex at 1:1,000 in the EHT. Latex and purified papain from C. papaya were effective against S. venezuelensis eggs and larvae in vitro, suggesting their potential use as an alternative treatment for strongyloidiasis.

Resposta de híbridos de milho ao uso de piraclostrobina na ausência de doenças / Corn hybrids responses to pyraclostrobin use in disease absences

Objetivando-se avaliar o efeito da aplicação de piraclostrobina em diferentes épocas e combinações de aplicação em dois híbridos simples de milho cultivados na safra de verão, realizou-se um experimento no município de Jataí, Goiás. Adotou-se o delineamento de blocos ao acaso no esquema fatorial 2 x 9 (híbridos x aplicações de piraclostrobina), com 4 repetições. As aplicações foram realizadas em diferentes combinações de fungicidas: presença ou ausência de piraclostrobina + tiofanato metílico + fipronil (100 g i.a.100 kg semente-1) no tratamento de sementes (V0) combinado com a aplicação de piraclostrobina (150 g i.a.ha-1) antes ou após a adubação de cobertura (V4 ou V6) combinado ou não com a aplicação de piraclostrobina + ciproconazole (137,25 g i.a.ha-1) em pré-pendoamento (VT) e uma testemunha (sem uso de piraclostrobina). Foram avaliados: atividade da enzima redutase do nitrato, índice de clorofila, altura de plantas, altura de inserção de espiga, diâmetro de colmo, porcentagem de folhas senescentes, severidade de Puccinia polysora Underw, massa de mil grãos, densidade e produtividade de grãos. Submeteram-se os dados ao teste F para verificação de significância; e para comparação de médias utilizou-se o teste de Tukey, ambos a 5% de probabilidade. Para a maioria dos caracteres avaliados observou-se diferença entre híbridos. Não foi observado efeito das aplicações de piraclostrobina e interação entre os fatores em questão. Conclui-se que não há efeito benéfico ou deletério da aplicação de piraclostrobina em diferentes épocas e combinações de aplicação sobre os dois híbridos simples de milho cultivados na safra de verão.(AU)

An experiment was conducted in Jataí, Goiás, Brazil, aiming to evaluate the effects of the application of pyraclostrobin at different times and with different application combinations in two simple hybrids of corn grown in the summer season. A randomized block design was adopted in a factorial 2 x 9 (hybrid x pyraclostrobinapplications) design, with 4 replications. The applications were performed in different combinations: presence or absence of pyraclostrobin + thiophanate methyl + fipronil (100 g a.i.100 kg seed-1) in seed treatment (V0) combined with pyraclostrobin (150 g a.i.ha-1) application before or after topdressing (V4 or V6) combined or not with pyraclostrobin + cyproconazole (137.25 g a.i.ha-1) application in pre-bolting (VT) and a control (without use of pyraclostrobin). The following evaluations were performed: activity of the nitrate reductase enzyme, chlorophyll index, plant height, corn cob insertion height, stem diameter, percentage of senescent leaves, severity of Puccinia polysora Underw, thousand grain weight, grains density, and grains yield. An F test was performed to analyze the significance, and for a means comparison, a Tukey test was used, both at 5% probability. Differences among hybrids were observed for most of the evaluated traits. There were no effects of the applications of pyraclostrobin and no interaction between the factors in question. It can, therefore, be concluded that there are not beneficial or deleterious effects of the application of pyraclostrobin at different times and with different application combinations in two simple hybrids of corn grown in the summer season.(AU)

Evaluation of the performance of different plastics used to seal nylon cDNA arrays / Avaliação da performance de diferentes plásticos usados para selar arranjos de cDNA em náilon

cDNA arrays are a powerful tool for discovering gene expression patterns. Nylon arrays have the advantage that they can be re-used several times. A key issue in high throughput gene expression analysis is sensitivity. In the case of nylon arrays, signal detection can be affected by the plastic bags used to keep membranes humid. In this study, we evaluated the effect of five types of plastics on the radioactive transmittance, number of genes with a signal above the background, and data variability. A polyethylene plastic bag 69 μm thick had a strong shielding effect that blocked 68.7 percent of the radioactive signal. The shielding effect on transmittance decreased the number of detected genes and increased the data variability. Other plastics which were thinner gave better results. Although plastics made from polyvinylidene chloride, polyvinyl chloride (both 13 μm thick) and polyethylene (29 and 7 μm thick) showed different levels of transmittance, they all gave similarly good performances. Polyvinylidene chloride and polyethylene 29 mm thick were the plastics of choice because of their easy handling. For other types of plastics, it is advisable to run a simple check on their performance in order to obtain the maximum information from nylon cDNA arrays.

Os arranjos de cDNA são uma poderosa ferramenta para o estudo de padrões de expressão gênica. Os arranjos em membranas de náilon apresentam ainda a vantagem de poderem ser reutilizados diversas vezes. Porém, um ponto bastante delicado em estudos de expressão gênica em larga escala é a sensibilidade. No caso de arranjos em membranas de náilon, a detecção dos sinais pode ser afetada pelo envoltório plástico utilizado para manter as membranas úmidas. Nesse estudo, nós avaliamos os efeitos de cinco tipos de plásticos na transmissão radioativa detectada, no número de genes com sinal acima da emissão de fundo e na variabilidade dos dados. O plástico produzido com polietileno com 69 μm de espessura apresentou uma forte interferência na emissão radioativa, bloqueando 68.7 por cento do sinal detectado. Este bloqueio na transmitância diminuiu o numero de genes detectados e aumentou a variabilidade dos dados. Outros plásticos mais finos tiveram resultados melhores. Apesar de plásticos feitos de cloreto de polivinilideno e cloreto de polivinila (ambos com 13 μm de espessura) e polietileno (29 e 7 μm de espessura) terem diferentes níveis de transmitância, todos apresentaram performances semelhantes nos testes realizados. Cloreto de polivinilideno e polietileno com 29 μm de espessura foram os plásticos escolhidos devido à facilidade de manuseio. Para outros tipos de plásticos, é recomendável realizar um teste de suas performances antes de utilizá-los para envolver membranas de náilon, de forma a obter o máximo de informação dos experimentos com arranjos de cDNA.