ABA-mediated proline synthesis in cowpea leaves exposed to water deficiency and rehydration

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Seed and Seedling Anatomy in Euterpe oleraceae Mart. during the Germination Process

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Control of algal growth on greenhouse surfaces using commercial algaecides

Greenhouses and nurseries provide ideal environments for facilitating the formation of nuisance algal mats. Algal growth poses safety concerns to horticulturists and stimulates the propagation of unwanted plant pests and pathogens. To date, few strategies and data are available to effectively manage algal problems. The effectiveness of five algaecides was tested on two varying surfaces of greenhouses in situ to elucidate the efficacy of chemical methods of removing algae. Moreover, Nostoc commune (Vaucher ex Bornet & Flahault) was treated on ceramic tiles in vitro, as it is a common alga in greenhouses and nurseries. We found that each algaecide had different effects, depending on the chemical applied, the surface to which the chemical was applied, and finally the types of algae that were targeted. Algaecides across the surfaces tested demonstrated that algal cell characteristics and communal makeup played an important role in algaecide efficacy, where mucilaginous algae were replaced by sheath-forming filamentous cyanobacteria. We found sodium carbonate peroxyhydrate to be the most effective chemical in terms of controlling Nostoc on tarp, gravel, and ceramic surfaces

Past cyanobacteria biodiversity in herbarium collections: a time travel to a lost world?

A pilot study of the cyanobacterial diversity in ten herbarium samples from the Smithsonian Institution (Washington DC, USA) was carried out. The samples had been collected between 1897 and 1964 in Antarctica, Alaska, Yellowstone Park and Austrian and American glaciers. The V3-V4 portion of the 16S rRNA gene was sequenced by multiplex 454 pyrosequencing and data was analyzed using the bioinformatic pipeline of Pessi et al. (2016). We obtained 131 OTUs (threshold of 97.5% 16S rRNA similarity), of which 74 were very closely related to existing sequences in public databases. Moreover, the diversity patterns were different between samples, ruling out an homogenization due to contaminations during the handling of herbarium samples since their collection and in our laboratory. The older specimen (1898) came from a pool at 46°C in Yellowstone Park with dominant sequences of Stigonema and Leptolyngbya, that are known from these biotopes. For the Antarctic samples taken in 1948-9 from Ross Island, in 1940 from Deception Island and in 1964 from Victoria Land, the DNA could be amplified in all cases and 55 OTUs were detected. Sequences of Nostoc sp., Microcoleus sp., Phormidesmis priestleyi, Leptolyngbya sp., and Timaviella sp. were retrieved. An Alaskan river specimen from 1949 yielded mostly Nostoc sequences, as could be expected from the herbarium label. This study gives access to the cyanobacterial community composition in a period where anthropogenic and climatic pressures were still low in the remote polar regions. We will assess if it is possible to detect changes in biogeographic patterns or shifts of genotypes towards more generalist ones.HERBA: Herbaria for the preservation of cyanobacterial diversity and biogeography studies : past and futur

Chromatographic analysis and antiproliferative potential of aqueous extracts of Punica granatum fruit peels using the Allium cepa test

Punica granatum L., conhecida como romanzeira, é originária da Ásia e encontra-se distribuída por todo Brasil. É usada para o tratamento de doenças inflamatórias, infecciosas e respiratórias. Em decorrência da grande utilização de recursos fitoterápicos, é necessário esclarecer à população sobre a grande quantidade de substâncias existentes nas plantas e sobre os benefícios e prejuízos de tais substâncias à saúde. O presente trabalho objetivou realizar a análise cromatográfica e o estudo da genotoxicidade dos extratos aquosos das cascas dos frutos de P. granatum através do teste de Allium cepa L. Para a montagem do experimento, foram utilizados 7 tratamentos: T1-água destilada, T2-chá 5 g.L-1, T3-chá 10 g.L-1, T4-glifosato a 9,6%, T5-glifosato para recuperação em água destilada, T6-glifosato para recuperação em chá 5 g.L-1 e T7-glifosato para recuperação em chá 10 g.L-1. As radículas foram coletadas e fixadas em etanol:ácido acético (3:1) por 24 horas, e armazenadas em álcool 70%, sob refrigeração. Realizou-se análise por cromatografia líquida de alta eficiência para quantificação dos compostos fenólicos. Nos extratos de P. granatum foram observados em maior quantidade: ácido gálico, catequina, ácido cafeico e rutina. Além disso, os extratos demonstraram potencial antiproliferativo, sem apresentar atividade antimutagênica e genotóxica.Punica granatum L., locally known as romanzeira, is native to Asia but found throughout Brazil. P. granatum is used for treating inflammatory, infectious and respiratory diseases. The aim of this study was to evaluate the chromatography and genotoxicity of an aqueous extract of P. granatum (pomegranate) fruit peel using the Allium cepa L. test. The experiment set-up entailed 7 treatments: T1-distilled water, T2-tea 5 g.L-1, T3-tea 10 g.L-1, T4-glyphosate at 9.6%, T5-glyphosate with subsequent recovery in distilled water, T6-glyphosate with subsequent recovery in tea 5 g.L-1 and T7-glyphosate with subsequent recovery in tea 10 g.L-1. The rootlets were collected and fixed in ethanol:acetic acid (3:1) for 24 hours, then stored in 70% ethanol under refrigeration. Analysis was performed using high performance liquid chromatography for the quantification of the extracted phenolic compounds. Gallic acid, catechin, caffeic acid, and rutin were abundant in the extracts of P. granatum. The extracts were found to exhibit antiproliferative potential but not antimutagenic or genotoxic activity

Comportamentais e Genéticos do Alcoolismo em uma Amostra da População do Vale do Rio Pardo, RS.

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