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Copyright of Journal of Seed Science is the property of Associacao Brasileira de Tecnologia de Sementes and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Increasing atmospheric CO2 concentrations ([CO2]) are unequivocal, widespread, and responsible for increased mean global temperatures and altered precipitation patterns. In this context, among the topics that need to be better understood are the changes in the water-related processes and gas exchange properties of plants grown under these conditions. Notably, the effects of climate change on coffee (Coffea spp.) production are particularly concerning given the importance of this commodity. Especially, it has been reported that coffee trees exhibit better photosynthetic efficiency when grown at higher [CO2] levels. In order to elucidate the mechanisms involved with this response, the seasonality of water-related processes, gas exchange, and carbohydrate metabolism were investigated using C. arabica var. Red Catuaí grown at ambient and high [CO2] under field conditions, at a free-air CO2 enrichment (FACE) facility for coffee, in Brazil. The trees were evaluated fortnightly, from November to February (hot and rainy—summer) and from June to September (cold and dry—winter). It was found that C. arabica trees grown under high [CO2] conditions exhibited increased photosynthetic rates (averaging 121% higher in summer and 45% higher in winter) in both seasons, without displaying any significant changes in the seasonal photosynthesis pattern. Additionally, there was a tendency for the coffee trees grown at high [CO2] to exhibit increased levels of soluble carbohydrates, organic acids, and amino acids in the leaves. Our findings suggest that coffee trees adapt to increased [CO2] through increased photosynthetic rates, enhanced stomatal conductance regulation, and augmented carbohydrate and organic acid synthesis. It is plausible that these features could help mitigate the effects caused by climate change. [ABSTRACT FROM AUTHOR]

Background: Our research group previously characterized the antioxidant and gastroprotective effects of Struthanthus marginatus (Loranthaceae), a medicinal herb used in Brazil as a healing agent. Objective: The aim of this study is to evaluate the chemical composition of aqueous extract of S. marginatus (AESm), as well as the mechanisms underlying its gastroprotective and ulcer healing properties using different protocols in mice. Materials and Methods: Gas chromatography-mass spectrometry and liquid chromatography/electrospray ionization-mass spectrometry-mass spectrometry/diode array detection analyses to evaluate the chemical composition of AESm were conducted. The antisecretory activity (basal or stimulated) was determined using the pyloric ligature method. The gastroprotective action of nitric oxide and sulfydryl groups (–SH groups) were evaluated using ethanol-induced gastric ulcer model. The healing ability was evaluated using an acetic acid-induced chronic ulcer. Results: Chromatographic analyses of AESm permitted to identify several compounds, including 3-trans-caffeoylquinic acid (3-trans-CGA), quercetin, and kaempferol as the major constituents. Oral treatment of animals with AESm (500 mg/kg/day) reduced the severity of ethanol-induced gastric damage similar to omeprazole and in a more pronounced manner than 3-trans-CGA. Such effect was significantly reduced in animals pretreated with Nω-nitro-L-arginine methyl ester. In addition, AESm inhibited gastric acid secretion in pylorus-ligated mice stimulated with histamine or pilocarpine similar to atropine or cimetidine, respectively. A decrease in acetic acid-induced gastric ulcers similar to that promoted by cimetidine was also observed. Conclusion: The results show that S. marginatus is rich in flavonoids and that these compounds contribute directly to the gastroprotective and ulcer healing effects of this herb. The inhibition of gastric secretion is the possible gastroprotective mechanism. Abbreviations Used: AESm: Aqueous Extract of S. marginatus; 3-trans-CGA= 3-trans-caffeoylquinic acid. [ABSTRACT FROM AUTHOR]

The persistence of viable seeds in the soil is an important way to assure plant propagation, especially for species which produce seeds with short lifespan. Poincianella pluviosa is a tree species which seeds have short to medium storability at room temperature. The comprehension of the maturation process is crucial to understand its strategy for propagation and it could provide tools to improve seed viability in ex situ conditions. Flowers were tagged in two consecutive cycles of maturation and pods were periodically harvested until dispersion. Seeds were classified based on their morpho-physiological features, capability to germinate and develop seedlings. The complete maturation process was attained 315-330 days after anthesis, a period longer than reported for seed viability at room temperature. The maximum dry mass and seed vigor were reached at the end of maturation, although elevated seedling production was obtained before physiological maturity. We suggest that the precocious ability to produce seedlings in a long maturation could be a strategy to overcome environmental constraints, as the species is distributed in a wide range of phytogeographic domains in Brazil. [ABSTRACT FROM AUTHOR]

BACKGROUND Banana and papaya are among the most important crops in the tropics, with a value amounting to millions of dollars per year. However, these fruits suffer significant losses due to anthracnose, a fungal disease. It is well known that certain seaweed extracts possess antifungal activity, but no published data appear to exist on the practical application of this property. In the present study, five organic Brazilian seaweed extracts were screened for their activity against banana and papaya anthracnose fungi. Furthermore, cytotoxic and mutagenic effects of the extracts were evaluated by the brine shrimp lethality assay and the Allium cepa root-tip mutagenicity test respectively, while their major components were identified by gas chromatography/mass spectrometry. RESULTS Strong fungus-inhibitory effects of Ochtodes secundiramea and Laurencia dendroidea extracts were observed on both papaya (100 and 98% respectively) and banana (89 and 78% respectively). This impressive activity could be associated with halogenated terpenes, the major components of both extracts. Only Hypnea musciformis extract showed cytotoxic and mutagenic effects. CONCLUSION The results of this study suggest the potential use of seaweed extracts as a source of antifungal agents with low toxicity to control anthracnose in papaya and banana during storage. © 2013 Society of Chemical Industry [ABSTRACT FROM AUTHOR]