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Currently, lead acid battery is extensively investigated owing to its prevalent use as a startinglighting and ignition device. An essential role for electrochemical reactions is played by the surface area available for conversion reactions and a possible approach is the use of nanostructured electrodes. In this work, lead dioxide nanostructured electrodes were tested in order to investigate the dependence of the charge and discharge behaviour on some parameters such as electrolyte concentration, and a new type of thin separator. In this last case, it is possible to reduce the size of the cell by using a very thin separator comparable to the nanostructured electrode thickness. Besides, a low concentration of electrolyte was also tested for studying its influence on the performance of a nanostructured electrode. Lead dioxide electrodes were cycled at 1C-rate and discharged to a cutoff voltage of 1.2 V up to 90% of the gravimetric capacity. Electrodes were assembled in a zero gap configuration using a commercial negative plate as counter-electrode with a large excess of active mass in comparison to the nanostructured one. Tests were conducted in very stressful conditions, in order to compare the behaviour of this new type of battery with that of the commercial one.

Molybdenum (Mo) is an essential trace element for plant growth, development, and production. However, there is little known about the function and effects of molybdenum in tomato plants. The present study assessed the influences of different Mo concentrations on four tomato F1 hybrids (“Bybal” F1, “Tyty” F1, “Paride” F1, and “Ornela” F1) grown using a soilless system with different Mo levels [0.0, 0.5 (standard NS), 2.0, and 4.0 μmol L−1, respectively]. The crop yield, plant vigor, fruit skin color, TA, fruit water content as well as the accumulation of SSC, and some antioxidant compounds such as lycopene, polyphenols and ascorbic acid were evaluated. The minerals concentration, including nitrogen (N), Mo, iron (Fe), and copper (Cu), were measured in tomato fruits. Results revealed that tomato plants grown with 2.0 μmol Mo L−1 compared to plants grown with 0.5 μmol Mo L−1 incurred a significant increase of total yield by 21.7%, marketable yield by 9.1%, aboveground biomass by 16.7%, plant height at 50 DAT by 6.5%, polyphenol content by 3.5%, ascorbic acid by 1.0%, SSC by 3.5%, N fruit content by 24.8%, Mo fruit content by 20.0%, and Fe fruit content by 60.5%. However, the Mo concentration did not significantly influence the average fruit weight, b∗ fruit skin color coordinate and TA. Furthermore, tomato fruits from plants grown with 2.0 μmol Mo L−1 showed a lower Cu fruit content (16.1%) than fruits from plants grown with 0.5 μmol Mo L−1 (standard NS). Consequently, our study highlights the different behavior of the tomato genotypes tested when subjected to different levels of Mo concentration in the nutrient solution. Nevertheless, taking all in consideration our results clearly suggest that a Mo fertilization of 2.0 μmol Mo L−1 effectively enhance crop performance and overall fruit quality of tomato.

Seed germination and early seedling growth are the plant growth stages most sensitive to salt stress. Thus, the availability of poor-quality brackish water can be a big limiting factor for the nursery vegetable industry. The exogenous supplementation of gibberellic acid (GA3) may promote growth and vigor and counterbalance salt stress in mature plants. This study aimed to test exogenous supplementation through foliar spray of 10&minus, 5 M GA3 for increasing salt tolerance of tomato and sweet pepper seedlings irrigated with increasing salinity (0, 25, and 50 mM NaCl during nursery growth. Tomato and sweet pepper seedlings suffered negative effects of salinity on plant height, biomass, shoot/root ratio, leaf number, leaf area, relative water content, and stomatal conductance. The foliar application of GA3 had a growth-promoting effect on the unstressed tomato and pepper seedlings and was successful in increasing salinity tolerance of tomato seedlings up to 25 mM NaCl and up to 50 mM NaCl in sweet pepper seedlings. This treatment could represent a sustainable strategy to use saline water in vegetable nurseries limiting its negative effect on seedling quality and production time.

Hydroponics need water of good quality to prepare a balanced nutrient solution that could allow plants to reach their maximum yield potential. The rising difficulties in finding water with good quality have led to the compelling necessity of identifying sustainable ways to use saline water, limiting its negative effect on crop yield and quality. The exogenous supplementation of plant growth regulators, such as gibberellic acid (GA3), can be effective in increasing plant growth and vigor, thus helping plants to better cope with salt stress. The aim of this study was to evaluate the feasibility to increase the salt tolerance of leaf lettuce and rocket grown in a floating system by adding GA3 (10&minus, 6 M) to mineral nutrient solutions (MNS) with increasing salinity (0, 10, and 20 mM NaCl). Leaf lettuce and rocket plants suffered a significant reduction of growth and yield, determined by the reduction of biomass, leaf number, and leaf area, even with moderate salt stress (10 mM NaCl). The supplementation of exogenous GA3 through the MNS allowed plants to substantially counterbalance salt stress by enhancing various morphological and physiological traits, such as biomass accumulation, leaf expansion, stomatal conductance and water and nitrogen use efficiency. The effects of salt stress and GA3 treatment varied according to the species, thus indicating that this interaction may improve salt tolerance by activating different adaptation systems.

Ecklonia maxima is a brown algae seaweed largely harvested over the last years and used to produce alginate, animal feed, fertilizers, and plant biostimulants. Their extracts are commercially available in various forms and have been applied to many crops for their growth-promoting effects which may vary according to the treated species and doses applied. The aim of the study was to characterize the effect of adding an Ecklonia maxima commercial extract (Basfoliar Kelp, 0, 1, 2, and 4 mL L−1) to the nutrient solution of a hydroponic floating system on growth, yield, and quality of leaf lettuce at harvest and during cold storage (21 days at 4 °C). The supplementation of the E. maxima extract through the mineral nutrient solutions, especially between 2 and 4 mL L−1, enhanced plant growth and improved the yield and many morphological and physiological traits (biomass accumulation, leaf expansion, stomatal conductance, water use efficiency, nitrogen use efficiency, etc.). Preharvest treatments with E. maxima extract were effective in delaying leaf senescence and extending the shelf-life of fresh-cut leaf lettuce. The delay in leaf decay of treated samples allowed to retain an overall quality over the threshold of marketability for up to 21 d of cold storage, especially using 2 mL L−1 of extract.

Molybdenum (Mo) is required in enzymes involved in a number of different metabolic processes, and is crucial for the survival of plants and animals. The influence of nutrient solutions containing four levels of molybdenum (0, 0.5, 1.5, and 3.0 &micro, mol/L) on growth, yield, and quality of lettuce, escarole, and curly endive grown in a hydroponic floating system was evaluated. Biometric, nutrient, and quality analyses were conducted to assess the response of each species to Mo. The results demonstrated that molybdenum is essential for harvesting marketable plants. Lettuce, escarole, and curly endive plants differed significantly in their response to molybdenum fertilization. The increase of Mo concentration in the nutrient solution was not harmful for plants and had no influence on yield and morphological traits of the leafy vegetables, however, it significantly affected some quality characteristics. Mo fertilization raised the nutritional quality by increasing ascorbic acid content up to 320.2, 139.0, and 102.1 mg kg&minus, 1 FW (fresh weight), and reducing nitrate content down to 1039.2, 1047.3, and 1181.2 mg kg&minus, 1 FW for lettuce, escarole, and curly endive, respectively. The addition of Mo in the nutrient solution increased the Mo content of plants up to 0.50, 4.02, and 2.68 &mu, g g&minus, 1 FW for lettuce, escarole, and curly endive, respectively. Increasing Mo supply to lettuce, escarole, and curly endive up to 3.0 &micro, mol L&minus, 1 could lead to a higher nutritional quality with no significant morphological alteration or yield loss.

Gibberellins (GAs) are growth hormones strongly involved in a wide variety of physiological activities. Currently, gibberellins are commercially used to enhance phenotypic characteristics, earliness, and productivity of many vegetable and ornamental crops. In this work, the efficacy of supplementation of low levels of gibberellic acid (0, 10&minus, 8, 10&minus, 6, and 10&minus, 4 M GA3) through the mineral nutrient solution of a floating system on yield and quality of leaf lettuce and rocket plants was tested. The marketability of plants was lost when 10&minus, 4 M GA3 was added to the mineral nutrient solution. This study demonstrated that the addition of 10&minus, 4 M GA3 exceeded the acceptable threshold for use in hydroponics production systems. Below the concentration of 10&minus, 4 M, the presence of GA3 in the mineral nutrient solutions (MNS), especially at 10&minus, 6 M GA3, stimulated plant growth and enhanced the yield. Various morphological and physiological traits were enhanced by GA3 treatments (biomass accumulation, leaf expansion, stomatal conductance, water use efficiency (WUE), Nitrogen use efficiency (NUE), etc.), with superimposable trends in both lettuce and rocket. The addition of 10&minus, 6 M GA3 to the nutrient solution of a hydroponic floating system can promote growth and quality of lettuce and rocket plants.

Borage (Borago officinalis L.) is a wild vegetable appreciated as a folk medicine and for culinary preparations. The introduction of borage as a specialized cultivation would allow for the diversification of vegetable crops and would widen the offerings of raw and minimally processed leafy vegetables. Thus, the aim of the research was to evaluate the quality and shelf-life of fresh-cut borage stored at different temperatures. Borage plants were grown during the autumn&ndash, winter season and immediately minimally processed after harvest. Fresh-cut borage leaves packed in sealed bags were stored at 2 or 6 &deg, C for 21 d. Weight loss, total soluble solids (TSS), titratable acidity (TA), ascorbic acid, nitrates, leaf color characteristics and overall quality were determined through the storage period. Borage plants were deemed suitable for minimal processing. Storage temperature significantly influenced the rate of quality loss. Borage leaves had an initial nitrate content of 329.3 mg kg&minus, 1 FW that was not affected by temperature or storage. TSS and TA were higher in leaves stored at 6 &deg, C. TSS, TA and ascorbic acid content increased during storage. Minimally processed borage leaves stored at 2 &deg, C had lower weight loss and leaf color modifications during storage and a longer shelf life than those stored at 6 &deg, C, so were still marketable after 21 d of storage.

Plant growth regulators are used in high-value vegetable crops during cultivation and after harvest to increase yield, enhance crop management, and improve or retain the produce quality. The aim of this work was to evaluate the quality characteristics during cold storage of minimally processed leaf lettuce and rocket, obtained from plants grown in a hydroponic floating system with mineral nutrient solutions (MNS) containing different levels of gibberellic acid (GA3). Plants were grown in greenhouse conditions on nutrient solutions containing 0, 10&minus, 8, and 10&minus, 6 M GA3. At harvest, lettuce and rocket were immediately processed as fresh-cut vegetables and stored for 21 d at 4 &deg, C. After processing, weight loss, total soluble solids, titratable acidity, ascorbic acid and nitrate content, leaf color characteristics, and overall quality were evaluated. Adding 10&minus, 6 M GA3 to the MNS of a floating system significantly increased the yield of leaf lettuce and rocket plants and of minimally-processed leaves. In addition, preharvest GA3 treatments had positive effects on delaying senescence and enhancing shelf-life of minimally processed lettuce and rocket. The slowed senescence of GA3-treated samples maintained an overall quality over the threshold of marketability in both lettuce and rocket for up to 21 d of cold storage.

Seeds-germination is among all physiological processes one of the most sensitive to stresses. The use of brackish water can slow down the water absorption of seeds and consequently all processes linked with the use of reserves of nutrients and the development of embryos. Laboratory experiments have been carried out to study the effects of salinity on basil (Ocimum basilicum L.), rocket (Eruca sativa L.) and parsley (Petroselinum hortense Hoffm.) germination. Standard germination techniques have been employed using Petri dishes containing filter paper saturated with 11 different concentrations of NaCl solutions, varying from 0 to 10 mS cm-1. It appears that salinity has not significantly reduced germination percentages of basil and rocket. The parsley has turned out to be less tolerant thus showing a connection between germination percentages decreases and salinity increases. Mean germination time has proved to be more directly influenced by water salinity. Higher levels of water EC have significantly delayed the seeds-germination of basil, rucole and parsley.

Nitrogen is an essential element, not only for its influence on the vegetativeproductive activity of the plants but also on fruit quality (color, shelf life, etc.). To achieve high production and quality standards, reducing environment impact, the S.Ag.A Department of Palermo carried out some researches to identify the most suitable fertilization to maximize the productive potential of fresh plug plants of two cultivars of strawberry widespread in the Sicilian area, 'Sabrosa®Candonga' and 'Nora', reducing Nitrogen inputs. The experimental design adopted was a splitplot, in which the main plot was the different doses of nitrogen, 120, 170, 220, 270, 320 kg/ha and the secondary one the cultivar. This research showed a rather wide variability of results, dependent on levels available for plants and doses distributed between the cultures. The seasonal pattern of production showed how the plot fertilized with 270 kg/ha has always achieved the highest harvest, but it's not significant for statistic analysis, in the early productive period (January-March) with the thesis treated with lower doses (120 and 170 kg/ha). The lowest doses (120 and 170 kg/ha) provided the firmest fruits, 735 g, with an high content in total soluble solids content, 7.3°Brix, and highest vitamin C, 53 mg/100 g of f.w., and a very bright orange-red color. It has been noted that the two cultivars fertilized with medium and low doses produced larger fruits, with a high soluble solids and vitamin C content. In conclusion, in greenhouses cultivation, the application of low doses of nitrogen achieves the same production, as higher doses, and high fruit quality, reducing environmental and production costs.

The most suitable techniques and use of F1 hybrids enable greenhouse production to achieve high yields, with crops all year round. In Sicily, greenhouse production of cucumber is for fresh use (slicers), producing large fruit. The cultivation technique most suited to greenhouses is the vertical single stem. However, an innovative technique being proposed is of cultivation on a trellis, eliminating lower branches, and training the remaining branches upwards (vertical shoot positioning, VSP). Cucumbers in the south of Italy are grown as the main crop or as a catch crop between 2 main crops. The crop should be rotated on the same soil only after 3-4 years with another crop, unless the land is thoroughly weeded, which is usually prohibitively expensive. One alternative to soil decontamination is hydroponic culture, which produces high yields and high quality. The cucumber has substantial nutritional requirements, but an excess of N can provoke a significant accumulation of nitrates, which in particular conditions (long storage periods, heat, and acidic pH) can transform into nitrites which are harmful to humans. This research therefore set out to investigate the possibility of cucumber cultivation using VSP and modifying the electrical conductivity of the nutrition solution from 1.5 mS/cm to 2,5 mS/cm, starting from the same mother solution. This test shows that VSP cultivation and the use of nutrition solutions with high levels of electric conductivity can produce greater yields and gourds with nitrate content lower than the max quantity permitted.