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Influence of hypoxia and NaCl salinity on sweet basil (Ocimum basilicum L.) grown hydroponically for the production of rosmarinic acid.
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Copper tolerance and accumulation on pelargonium graveolens l’hér. Grown in hydroponic culture
No full textHeavy metal contamination is a major health issue concerning the commercial production of medicinal and aromatic plants (MAPs) that are used for the extraction of bioactive molecules. Copper (Cu) is an anthropogenic contaminant that, at toxic levels, can accumulate in plant tissues, affecting plant growth and development. On the other hand, plant response to metal-induced stress may involve the synthesis and accumulation of beneficial secondary metabolites. In this study, hydroponically grown Pelargonium graveolens plants were exposed to different Cu concentrations in a nutrient solution (4, 25, 50, 100 μM) to evaluate the effects Cu toxicity on plant growth, mineral uptake and distribution in plants, some stress indicators, and the accumulation of bioactive secondary metabolites in leaf tissues. P. graveolens resulted in moderately tolerant Cu toxicity. At Cu concentrations up to 100 μM, biomass production was preserved and was accompanied by an increase in phenolics and antioxidant capacity. The metal contaminant was accumulated mainly in the roots. The leaf tissues of Cu-treated P. graveolens may be safely used for the extraction of bioactive molecules
Influenza di sistemi colturali artificiali sul contenuto di acido rosmarinico in basilico (Ocimum basilicum L.)
No full textIodine biofortification of sweet basil and lettuce grown in two hydroponic systems
Full text linkTwo hydroponic techniques (floating system and aeroponics) were assessed for iodine (I) biofortification of sweet basil (Ocimum basilicum L.) and baby-leaf lettuce (Lactuca sativa L.). Iodine was supplemented by adding KI into the nutrient solution to achieve a final I concentration of 10 μM. Shoot biomass production and leaf concentration of I, nitrates, total phenols and pigments were measured on the occasion of two successive cuts, 14 and 28
days after transplanting. In both the hydroponic systems, the supplementation of KI represented an effective method for the biofortification of basil as it did not affect the plant growth, while it moderately reduced the biomass production in lettuce. Leaf I accumulation occurred to a greater extent in aeroponics than the floating system in both species. In KI-treated basil plants, leaf I content ranged between 9.76 and 23.58 mg kg− 1 FW.
Consequently, 6 g of fresh basil leaves, which is contained in a portion of Italian pesto sauce (12 g), could satisfy 40%–94% of the Recommended Daily Intake (RDI) of iodine for healthy adults (150 μg day− 1). In lettuce, leaf I contents of first-cut leaves were 1.55 and 3.60 mg kg− 1 FW, in the floating system and aeroponics, respectively. Therefore, a serving size of 26 g of lettuce containing I from 1.55 (floating culture) to 3.60 (aeroponics) mg kg− 1 FW could satisfy 27 % to 62 % of the RDI of iodine.
Lettuce grew much less in the floating system than aeroponics, probably because of the lower dissolved oxygen level in the nutrient solution as compared to aeroponics. Basil was less sensitive to the oxygen availability in the root zone, since no differences were detected between the two hydroponic systems in terms of fresh and dry biomass
Copper and Zinc Accumulation in Young Leaves of Eruca sativa (L.) Grown in Soilless Culture
Full text linkHeavy metals are environmental pollutants that cause toxicity in plants and represent a risk for human health, linked to bioaccumulation through the food chain. However, excess accumulation may not occur in young plants in the early stages of exposure to the toxic element. In the present work, rocket (Eruca sativa L.) plants grown in hydroponics were exposed for three weeks to excess concentrations (25, 50, or 100 μM) of Cu or Zn in the nutrient solution and were more sensitive to Cu than Zn toxicity. However, a significant decrease in the leaf biomass production as compared with the control was observed only after two or three weeks, and only minor signals of metal-induced adverse effects were evidenced concerning photosynthesis, oxidative stress indicators, antioxidant metabolites, and macronutrients. After two or three weeks, the leaf level of Cu occasionally approached the upper value associated with the recommended limits of dietary intake for human adults. However, as rocket leaves are commercialized when they achieve a 10–15 cm length, after one week of cultivation in perlite, the plants had an adequate size without metal contamination and could be considered suitable for the food market, even after exposure to Cu or Zn concentrations up to 100 μM
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Effects of NaCl on Hydroponic Cultivation of Reichardia picroides (L.) Roth
Full text linkWild edible plant species are often more tolerant to salinity than many crop plants. Consid-ering the salinization of irrigation water that is progressively affecting the Mediterranean region and the market demand for new plant foods, the cultivation of wild edible species could represent a valid alternative to conventional vegetable crops. In this study, Reichardia picroides (L.) Roth, a widespread spontaneous herb of ethnobotanical tradition, was grown for four or six weeks under a greenhouse in a floating system for the production of baby leaves. In order to improve the nutraceutical quality of the tissues, the plants were exposed to the following NaCl concentrations in the nutrient solution: 1.7 (control), 25, 50, and 100 mM. The results showed that a 4-week growing period in a floating system with 50 mM NaCl in the nutrient solution increased the content of bioactive molecules without affecting the fresh yield. After six weeks of cultivation, despite a decrease in biomass production as compared with the control, the leaves of salt-treated plants contained higher levels of bioactive molecules along with lower amounts of nitrate ion
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
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