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Edible coating is extensively applied for fresh produce preservation. In the present study, Aloe vera gel (AV) alone or combined with sage essential oil (EO; 0.1% or 0.5%) was used as fruit edible coating in tomatoes. Following treatments, tomatoes were stored at 11 °C and 90% relative humidity (RH) up to 14 days and analyzed for quality maintenance compared with uncoated fruits (control). Results showed that both AV and EO decreased decay symptoms with more pronounced effects on low EO concentration (i.e., 0.1%). The application of 10% of AV coating decreased fruit ethylene emission while EO (0.1% and 0.5%) application increased ethylene emission and respiration rates. AV coating decreased acidity, β-carotene, lycopene content and maintained fruit firmness. High levels of EO (0.5%) increased weight loss but decreased fruits’ redness, chroma, total soluble solids, acidity, β-carotene and lycopene content. Total phenolic content and antioxidants maintained or increased during storage when treated with AV and/or EO. Low levels of EO (0.1%) maintained or improved fruit quality characteristics during storage, and this was mirrored by the sensory evaluation preference (including the AV application) and quality related attributes.

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The SW application could alter the detrimental effects of K deficiency during lettuce growth and storage of processed products. © 2018 Society of Chemical Industry.

The Middle East, the cradle of viticulture and wine production, is gradually but steadily becoming hotter and drier because of climate change (CC). In the current study, we evaluated the effect of tillage and irrigation on yield and quality characteristics of the heat-resistant, indigenous red-grape variety Maratheftiko for one year. Yield increased (two-fold) in vines with irrigation and tillage compared to tillage with no irrigation. The absence of tillage buffered the negative effect of the lack of irrigation on yield. At the veraison stage, leaf stomatal conductance decreased in non-irrigated vines, independently of the application of tillage or not. At veraison, tillage increased (up to 27.5%) phenolics when compared to no tillage in non-irrigated vines. Vines accumulated more N, P, and K and less Mg during the flowering stage compared to veraison. At veraison, irrigation decreased K content in vines subjected to tillage and decreased Mg content in vines subjected to no tillage. Total soluble solids and anthocyanins of berries increased with the absence of irrigation and tillage. Total phenolics increased with tillage in both irrigated and non-irrigated plants. Our results indicate that no tillage systems may be viable as an adaptation strategy in the context of CC.

No abstract

Irrigation with saline water causes significant crop yield loss. However, short-term saline application might cause less negative effects on yield yet at the same time improve quality aspects of edible products. Tagetes (Tagetes patula L.) plants were subjected to salinity (0, 50, and 100 mM NaCl) and harvested flowers were stored up to 14 days in passive modified atmosphere packaging (with or without ethanol application). Salinity of 100 mM NaCl decreased plant biomass and plant size (i.e., height) and had a negative effect on physiological processes such as stomatal closure and chlorophylls content decrease. Salinity increased flower polyphenols, antioxidant activities, and total carotenoids but decreased anthocyanins, and greater impacts were found at salinity of 100 mM NaCl, providing higher antioxidant value of the edible flowers. Short-term saline exposure of tagetes plants activated metabolic processes and as a result there was an accumulation of minerals such as N, P, Na, and Zn on edible flowers. During storage, salinity maintained but ethanol application increased the flower CO2 production. Ethanol application decreased the decay of flowers subjected to 100 mM NaCl. Flower weight losses and marketability accelerated at salinity of 100 mM NaCl after 14 days of storage. Tagetes flowers demonstrated induction in both non-enzymatic (i.e., proline content) and enzymatic mechanisms (catalase) to overcome stress caused by salinity during harvest stage and/or ethanol at storage. Our results have shown that short-term exposure to salinity and/or ethanol is able to achieve higher carotenoids and anthocyanins levels and these compounds can be considered as a new source of nutraceuticals.

The effect of climate change (CC) on viticulture in Europe is of great concern and several international and indigenous grapevine cultivars have been examined for their adaptation to CC. In this study we focused on the short-term effects of light and moderate drought stress (DS) as well as heat stress (HS) on physiological and biochemical stress markers in Maratheftiko cultivar. We showed that leaf photosynthetic rate was decreased with DS and HS after 8 and 20 days. The leaf stomatal conductance was decreased in the case of DS after 8 days, while no differences could be found due to HS. Total phenols and flavonoids content and antioxidant capacity (FRAP and ABTS) were increased and seemed to be dependent on the relevant DS, HS and the period of stress exposure. Chlorophyll fluorescence was decreased in 50% volumetric water content (VWC) after 8 days of DS compared with the 100% VWC (control treatment). Leaf K and P content increased in moderate (50% VWC) irrigation stress and HS. Leaf hydrogen peroxide and lipid peroxidation increased after 8 days of DS, and this resulted in the increase of antioxidant enzymes activity. Overall, Maratheftiko performance against environmental stresses is related more to short-term DS than HS.