Drogoudi P.D.,Pomology Institute |
Pantelidis G.,Pomology Institute |
Bacchetta L.,ENEA |
De Giorgio D.,Italian Agricultural Research Council |
And 3 more authors.
International Journal of Food Sciences and Nutrition | Year: 2013
Almond protein and potassium (K), phosphorus (P), calcium (Ca) and magnesium (Mg) contents were determined in 72 cultivars and accessions grown in France, Greece and Italy, as part of the networking of European SAFENUT AGRI GEN RES project, which aimed to explore and valorize the almond genetic resources in Europe. Great variation was found in the nutrient content and the amount of nutrient supplied when consuming the recommended daily amount of one serving of almond, among the different genotypes assayed. The variation among the different genotypes was greatest for Ca, followed by the protein content; the latter also exhibited the lowest variation considering the harvest year. Results from a principal component analysis showed that P and Mg were the most discriminant elements for categorizing samples. Cluster analysis showed groups of samples with interesting characteristics for breeding. There was no clear distinction among the different origins of samples. Correlation analyses between weather conditions and the nutrients assayed showed that the mean temperature recorded in the period between March and September was positively correlated with Ca and P only in France, a place where the greatest climatic difference between years was observed. © 2012 Informa UK, Ltd.
Doupis G.,Institute for Olive Tree and Subtropical Plants |
Bosabalidis A.M.,Aristotle University of Thessaloniki |
Patakas A.,University of Patras
Theoretical and Experimental Plant Physiology | Year: 2016
The effects of drought and enhanced UV-B radiation on photosynthetic and leaf anatomical characteristics were studied in two different grapevine genotypes (Vitis vinifera L. cvs ‘Romeiko’ and ‘Soultanina’), which were grown outdoors in 25 L pots containing a peat:perlite:sand (3:1:1, v/v/v) potting mix. The plants were subjected to three levels of UV-B radiation (i) ambient, (ii) intermediate (ambient plus 15 % UV-B radiation), (iii) high (ambient plus 30 % UV-B radiation) and two irrigation regimes (i) well-watered (irrigated on daily basis to substrate capacity) and (ii) drought-stressed (irrigated daily with the 50 % of the amount of water provided to well-watered plants). Both abiotic stressors induced a significant decrease in net photosynthesis (Pn) while the combination of drought and elevated UV-B radiation appeared to have synergistic effects on photosynthetic rate. At leaf anatomical level, drought resulted in the development of idioblastic cells in leaves of both grapevine varieties as well as in the reduction of leaf expansion rate, total lamina thickness and total biomass per leaf area whereas leaf tissue density considerably increased. On the other hand, enhanced UV-B radiation did not affect leaf anatomical characteristics of both genotypes in a similar way. In particular, different responses, closely depended to UV-B levels applied, were observed concerning the chlorenchymatic tissue and total lamina thickness. Moreover, the stimulation of UV-B absorbing compounds biosynthesis under enhanced UV-B radiation, could not manage to preserve photosynthetic performance. The implication of the watering regime and the UV-B in the induction of leaf anatomical and morphological alterations in net photosynthesis is discussed. © 2016, Brazilian Society of Plant Physiology.
Doupis G.,Institute for Olive Tree and Subtropical Plants |
Bertaki M.,Institute for Olive Tree and Subtropical Plants |
Psarras G.,Institute for Olive Tree and Subtropical Plants |
Kasapakis I.,Institute for Olive Tree and Subtropical Plants |
Chartzoulakis K.,Institute for Olive Tree and Subtropical Plants
Scientia Horticulturae | Year: 2013
The effects of variable water supply were investigated in 50-year-old Olea europaea (cv "Koroneiki") L. trees grown in an experimental orchard located in northwest Crete. The trees were subjected to four irrigation treatments: rainfed (RF), full irrigation (FI) with 100% of the crop evapotranspiration (Etc.) level and two deficit irrigation treatments, FRDI-fully irrigated, that received no irrigation water from July 12 to August 18 and DRDI-irrigated with 60% of ETc level, that received no irrigation water from July 12 to August 18. The effects of watering regime on soil moisture content, plant water status, gas exchange characteristics, chlorophyll content, antioxidant enzyme activities, i.e. superoxide dismutase (SOD; EC 22.214.171.124), catalase (CAT; EC 126.96.36.199), ascorbate peroxidase (APX; EC 188.8.131.52) and guaiacol peroxidase (GPX; EC 184.108.40.206) and on malondialdehyde (MDA) levels were evaluated. There were no marked differences between FI and FRDI treatments, except at the end of the no-watering period. On the contrary, stem water potential (Ψ) was affected by the level of water supply, leading to reduced stomatal conductance (gs) and carbon assimilation rate (Pn) in DRDI treatment. DRDI plants exhibited a close relation between photosynthetic rate (Pn) and stomatal conductance (gs), suggesting that stomatal closure is the dominant limitation to photosynthesis. Chlorophyll degradation and enhanced synthesis of carotenoids assisted plant to maintain its physiological processes under the water deficit and high light conditions. Olive tree was able to restore stem water potential (Ψ) after rewatering, and the recovery of leaf water status was coupled with an up-regulation of leaf gas exchange characteristics in DRDI plants. Leaves grown under rainfed conditions revealed signs of oxidative stress as indicated by the increased levels of lipid peroxidation, whereas irrigation mitigated the oxidative damage at leaf level in DRDI plants. Superoxide dismutase, ascorbate peroxidase and guaiacol peroxidase activity was increased in DRDI leaves, while catalase activity was inhibited. On the contrary, the lower expression of the enzymatic antioxidant system under rainfed conditions did not allow a better protection against a more pronounced oxidative stress. © 2013 Elsevier B.V.
Tzortzakis N.,Institute for Olive Tree and Subtropical Plants |
Sergentani C.,Institute for Olive Tree and Subtropical Plants
Acta Horticulturae | Year: 2015
The effects of heat stress (HS) and/or calcium chloride (CaCl2) on loquat (Eriobotrya japonica Lindl. 'Trouloti') fruit quality and storability were investigated in atmospheric air (AA - continuous air open flow system). Loquats were dipped in a water bath (at 45°C for 10 min, HS) and/or in CaCl2 (2% w/v for 10 min) and then stored under AA conditions at 5.5°C for 0, 15 and 30 days. A batch of fruits was removed after 0, 15, and 30 days to AA and stored for an additional 5 days at room temperature (RT). Loquat firmness was maintained in fruits treated with HS+CaCl2 after 5 days at RT and this was evident (including CaCl2 application) in fruits stored up to 30 days at 5.5°C. Similarly, under AA conditions, HS+CaCl2 and CaCl2 increased fruit sweetness and reduced acidity. The HS+CaCl2 increased (up to 50%) the respiration rate at 15 days of storage. On the other hand, total phenols decreased in fruits treated with HS+CaCl2 and stored up to 30 days at 5.5°C, while fruits stored at RT did not change. The number of fruits with brownish discoloration decreased (up to 39%, compared to controls) in fruits treated with HS+CaCl2 or CaCl2 (averaging only 10% of total fruit). HS alone accelerated browning and fruit decay development. Fruits stored for 5 days at RT following exposure to HS and/or CaCl2 increased respiration rate, sweetness and browning. No major differences were observed in fruit dry matter content and water loss. Following sensory evaluation, all panelists identified differences among treatments, with the HS+CaCl2 treatment giving the best preference (90%), maintaining loquat appearance and sweetness and no detected differences in fruit aroma and texture. Thus, the HS+CaCl2 on loquat maintained fruit quality, as indicated by panelists' preference.