Productivity of two stevia varieties under reduced irrigation and fertilization inputs     

Ioannis Vasilakoglou  Dimitrios Kalfountzos  Nikolaos Gougoulias  Charalampos Reppas 《Archives of Agronomy and Soil Science》2016,62(4):457-472

A 3-year field study was conducted in central Greece to determine the productivity of two stevia [(Stevia rebaudiana (Bertoni) Bertoni] varieties (‘Morita’ and ‘Candy-stevia’) under normal and reduced irrigation (100% and 75% of the evapotranspiration) and fertilization [1:0.8:1.1 or 1:0.4:0.8 N:P:K ratio in the first year and only N fertilization (100% or 74% of the recommended rate) in the second and third years] inputs. Averaged across years, stevia cv. Morita achieved greater dry leaf yield (3.48 t ha^?1) than the cv. Candy-stevia (2.85 t ha^?1). Irrigation and fertilization inputs did not significantly affect stevia cv. Morita dry leaf and steviol glycosides (stevioside plus rebaudioside-A) yields; however, decreasing irrigation and fertilization caused slight reduction of cv. Candy-stevia yields. In cv. Morita leaves, the concentrations of stevioside and rebaudioside-A ranged from 5.97% to 7.78% and 3.73% to 4.79%, respectively, while the corresponding concentrations in cv. Candy-stevia leaves were 8.21–9.36% and 3.89–6.33%. Conclusively, both stevia varieties could achieve satisfactory dry leaf biomass and steviol glycosides yield, even when grown under reduced irrigation (at 75% of evapotranspiration) and reduced N fertilization (74% of the recommended rate). Thus, stevia could represent an alternative crop to tobacco in the Mediterranean conditions.  相似文献   

Recent Modifications of Chitosan for Adsorption Applications: A Critical and Systematic Review     

George Z. Kyzas  Dimitrios N. Bikiaris 《Marine drugs》2015,13(1):312-337

Chitosan is considered to be one of the most promising and applicable materials in adsorption applications. The existence of amino and hydroxyl groups in its molecules contributes to many possible adsorption interactions between chitosan and pollutants (dyes, metals, ions, phenols, pharmaceuticals/drugs, pesticides, herbicides, etc.). These functional groups can help in establishing positions for modification. Based on the learning from previously published works in literature, researchers have achieved a modification of chitosan with a number of different functional groups. This work summarizes the published works of the last three years (2012–2014) regarding the modification reactions of chitosans (grafting, cross-linking, etc.) and their application to adsorption of different environmental pollutants (in liquid-phase).  相似文献   

Fishermen's perception on the sustainability of small‐scale fisheries and dolphin–fisheries interactions in two increasingly fragile coastal ecosystems in western Greece          下载免费PDF全文

Joan Gonzalvo  Ioannis Giovos  Dimitrios K. Moutopoulos 《水产资源保护:海洋与淡水生态系统》2015,25(1):91-106

An experimental simulation of moisture distribution and its uniformity within the soil profile under laboratory conditions     

Ioannis?GravalosEmail author  Anastasios?Georgiadis  Dimitrios?Kateris  Theodoros?Gialamas  Evagelos?Bompolas  Zisis?Tsiropoulos  Avgoustinos?Avgoustis  Panagiotis?Xyradakis 《Precision Agriculture》2017,18(1):19-36

This research is a study on the relationship of irrigation water treatments and soil moisture distribution uniformity (DU). Soil moisture distribution was based on long-term data sets that were collected using a novel electromagnetic sensor-based platform moving inside sub-surface horizontal access-tubes. The research was conducted under controlled laboratory conditions in a soil tank. The irrigation treatments regarding two case studies under dry and wet soil conditions (from permanent wilting point to field capacity) were conducted for a period of 115 and 110 days respectively. In dry soil conditions, the irrigation water treatments strongly affect the DU of soil moisture that can be achieved constantly using non-uniform irrigation treatments. In contrast, the DU of soil moisture in wet soil conditions was maintained at a high percentage and was slightly affected by irrigation treatments. However, obtaining accurate soil moisture information at a large scale over a long period can be used to improve water use efficiency.  相似文献   

Time Consumption and Production Costs of Two Small-Scale Wood Harvesting Systems in Northern Greece     

Dimitrios Koutsianitis  Petros A. Tsioras 《Small-Scale Forestry》2017,16(1):19-35

A field-based study was carried out to determine the productivity and production cost of the tree length (TL) and the wood assortment (WA) systems implemented under small-scale forestry conditions in two Scots pine stands in Northern Greece. Tree felling and processing productivity were estimated at 8.64 m³ per productive machine hour (PMH^?1) and 10.21 m³ PMH^?1, respectively. Wood felling and processing times were strongly dependent on dbh and total tree volume. However, when manual debarking was also considered the productivity rates decreased to 1.96 and 1.43 m³ PMH^?1, respectively. Skidding productivity was calculated to be 3.35 m³ PMH^?1 for TL and 7.17 m³ PMH^?1 for WA, respectively. Strong correlations have been found between the net skidding time and (a) the skidding distance and (b) the load per turn in both wood harvesting systems. Production costs varied greatly, from 19.38 € m^?3 up to 44.81 € m^?3 of roundwood depending on the harvesting system and the inclusion of debarking. The findings suggest that the WA system is more efficient in terms of productivity and production cost than TL, and that there is a substantial optimization potential. The optimization potential can be encoded in four suggestions: (a) opening up of more forest roads to reduce high skidding times, (b) replacement of manual debarking by mechanical debarking at the sawmill, (c) replacement of old pieces of equipment with newer ones and (d) training of the existing workforce.  相似文献   

Characterization of iron oxides in Fe-rich concretions from an imperfectly-drained Greek soil: a study by selective-dissolution techniques and X-ray diffraction     

Dionisios Gasparatos  Dimitrios Tarenidis 《Archives of Agronomy and Soil Science》2013,59(4-5):485-493

Fe-rich concretions commonly occur in Greek soils with alternating drying and waterlogging periods. This study was conducted to characterize the iron oxides in Fe-rich concretions from the upper solum of an Alfisol with seasonal perched water table by the combination of selective dissolution and X-ray diffraction (XRD) techniques. The results showed that more than 75% of the total iron (Fet) was associated with the crystalline and the amorphous Fe oxides, indicating a strong accumulation of free iron oxides (Fed) in concretions. Amorphous iron compounds (Feo) was present at high concentrations and fluctuated with profile depth. The active Fe ratio (Feo/Fed) values that ranged from 0.35 to 0.41 reflected an association of poorly crystalline goethite with some ferrihydrite. The XRD data showed that the Fe-rich concretions consisted of quartz, feldspars, illite and gypsum. The mineralogy of iron oxides in concretions was determined by comparison of XRD patterns for dithionite-citrate-bicarbonate (DCB) treated (deferrated) and untreated (non-deferrated) samples. Poorly crystalline goethite as demonstrated by broad lines in the diffraction patterns and ferrihydrite were the iron oxides detected in the concretions. This mineral assemblage appears to be related to the pedoenvironmental conditions in which the concretions were formed and indicates that the mechanisms governing the formation of crystalline Fe oxides from ferrihydrite are retarded by the presence of crystallization inhibitors.  相似文献   

Ascorbic acid–cyclodextrin complex alters the expression of genes associated with lipid metabolism in bovine in vitro produced embryos     

Viviana Torres  Meriem Hamdi  Veronica Maillo  Rodrigo Urrego  Jose Julian Echeverri  Albeiro Lpez‐Herrera  Alfonso Gutirrez‐Adn  Dimitrios Rizos  Maria Jesús Snchez‐Calabuig 《Reproduction in domestic animals》2019,54(1):55-62

Ascorbic acid (AC) used as antioxidant in embryo culture is very sensitive and degrades unavoidably in aqueous solution. Methyl‐β‐cyclodextrin (CD) improved the stability of AC in solution to elevated temperature, light, humidity and oxidation. The aim of this study was to evaluate the effect of the complex AC‐CD during in vitro maturation (IVM) or in vitro culture (IVC) on oocyte developmental competence and subsequent embryo development and quality. AC‐CD (100 µM) was added to IVM media, and maturation level and embryo development were examined. Matured oocytes, their cumulus cells and produced blastocysts were snap‐frozen for gene expression analysis by RT‐qPCR. Besides, in vitro‐produced zygotes were cultured with 100 µM of AC‐CD and blastocysts were as well snap‐frozen for gene expression analysis. A group without AC‐CD (control^?) and other with CD (control⁺) were included. No differences were found on maturation, cleavage or blastocyst rates. However, in matured oocytes, AC‐CD downregulated BAX, GPX1 and BMP15. In cumulus cells, AC‐CD downregulated BAX/BCL2 and GSTA4 while upregulated BCL2 and CYP51A1. The expression of SL2A1, FADS1, PNPLA and MTORC1 was downregulated in blastocysts derived from oocytes matured with AC‐CD, while in blastocysts derived from zygote cultured with AC‐CD, CYP51A1 and IGF2R were downregulated and PNPLA2 was upregulated. In conclusion, AC‐CD in both IVM and IVC media may reduce accumulated fat by increasing lipolysis and suppressing lipogenesis in blastocysts derived from both oocytes and zygotes cultured with AC‐CD, suggesting that CD improves the quality of embryos and bioavailability of AC during IVM and IVC.  相似文献   

An approach to study the local embryo effect on gene expression in the bovine oviduct epithelium in vivo     

Beatriz Rodríguez‐Alonso  Meriem Hamdi  Jos María Snchez  Veronica Maillo  Alfonso Gutierrez‐Adan  Pat Lonergan  Dimitrios Rizos 《Reproduction in domestic animals》2019,54(12):1516-1523

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Eating out of home and its correlates in 10 European countries. The European Prospective Investigation into Cancer and Nutrition (EPIC) study     

Orfanos P  Naska A  Trichopoulos D  Slimani N  Ferrari P  van Bakel M  Deharveng G  Overvad K  Tjønneland A  Halkjaer J  Santucci de Magistris M  Tumino R  Pala V  Sacerdote C  Masala G  Skeie G  Engeset D  Lund E  Jakszyn P  Barricarte A  Chirlaque MD  Martinez-Garcia C  Amiano P  Quirós JR  Bingham S  Welch A  Spencer EA  Key TJ  Rohrmann S  Linseisen J  Ray J  Boeing H  Peeters PH  Bueno-de-Mesquita HB  Ocke M  Johansson I  Johansson G  Berglund G  Manjer J  Boutron-Ruault MC  Touvier M  Clavel-Chapelon F  Trichopoulou A 《Public health nutrition》2007,10(12):1515-1525

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Dietary patterns and survival of older Europeans: the EPIC-Elderly Study (European Prospective Investigation into Cancer and Nutrition)     

Bamia C  Trichopoulos D  Ferrari P  Overvad K  Bjerregaard L  Tjønneland A  Halkjaer J  Clavel-Chapelon F  Kesse E  Boutron-Ruault MC  Boffetta P  Nagel G  Linseisen J  Boeing H  Hoffmann K  Kasapa C  Orfanou A  Travezea C  Slimani N  Norat T  Palli D  Pala V  Panico S  Tumino R  Sacerdote C  Bueno-de-Mesquita HB  Waijers PM  Peeters PH  van der Schouw YT  Berenguer A  Martinez-Garcia C  Navarro C  Barricarte A  Dorronsoro M  Berglund G  Wirfält E  Johansson I  Johansson G  Bingham S  Khaw KT  Spencer EA  Key T  Riboli E  Trichopoulou A 《Public health nutrition》2007,10(6):590-598

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