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61.
Fruit from Granny Smith, Fyriki, Fuji Kiku 8, and Imperial Double Red Delicious apple (Malus domestica Borkh.) trees planted in single or double rows, were harvested from different positions in the canopy, during the last month before commercial harvest. Fruit physico-chemical and antioxidant capacity, using the radical DPPH, were measured, in skin and flesh tissue. Greater total phenol content and total antioxidant capacity per fresh weight and serving portion of skin and flesh tissue, were found in Imperial Double Red Delicious and Fyriki apples, compared to Granny Smith and Fuji Kiku 8. The variation among cultivars in antioxidant contents was greater in peeled, compared with unpeeled fruit, highlighting the importance of eating unpeeled fruit. During the last two weeks before commercial harvest the total phenol content and total antioxidant capacity per fresh weight increased in skin of Granny Smith (by 24% and 42%, respectively) and Fuji Kiku 8 (by 19% and 27%, respectively). Fruit from the more sun—exposed parts of canopy had usually better red coloration and the effect was more pronounced in Fuji Kiku 8 and Fyriki, followed by Imperial Double Red Delicious and a lower effect was found in Granny Smith. Greater total soluble solid content, but not flesh firmness, were also found in fruit from the more sun—exposed parts of canopy, in all cultivars. The skin of fruit from the upper positions in the canopy had greater total phenol content and total antioxidant capacity, in all cultivars, apart from Fyriki. Antioxidant contents in flesh tissue were also greater in the upper positions of canopy in Fuji Kiku 8 and Imperial Double Red Delicious, and to our knowledge this is the first report on plant canopy effects on apple flesh antioxidant compounds. 相似文献
62.
Georgios Tsiotas Athanassios A. Argiriou 《Journal of Agricultural, Biological & Environmental Statistics》2011,16(3):371-388
A statistically efficient approach is adopted for modeling spatial time-series of large data sets. The estimation of the main
diagnostic tool such as the likelihood function in Gaussian spatiotemporal models is a cumbersome task when using extended
spatial time-series such as air pollution. Here, using the Innovation Algorithm, we manage to compute it for many spatiotemporal
specifications. These specifications refer to the spatial periodic-trend, the spatial autoregressive moving average, the spatial
autoregressive integrated and fractionally integrated moving average Gaussian models. Our method is applied to daily pollutants
over a large metropolitan area like Athens. In the applied part of our paper, we first diagnose temporal and spatial structures
of data using non-likelihood based criteria, such as the empirical autocorrelation and covariance functions. Second, we use
likelihood and non-likelihood based criteria to select a spatiotemporal model among various specifications. Finally, using
kriging we regionalize the resulting parameter estimates of the best-fitted model in space at any unmonitored location in
the Athens region. The results show that a specific autoregressive integrated moving average spatiotemporal model can optimally
perform in within and out of spatial sample estimation. Supplemental materials for this article are available from the journal
website. 相似文献
63.
64.
Theodora Karanisa Alexios A. Alexopoulos Georgios Tsaniklidis Ioannis C. Karapanos Konstantinos A. Akoumianakis 《Potato Research》2016,59(4):345-356
Chemical agents may be used to overcome dormancy in potato tubers so as to permit early planting. In this paper, the effect of carbon disulphide on sprouting and related metabolic processes in potato tubers grown from true potato seed (TPS) was investigated. Carbon disulphide was applied to potato tubers derived from TPS, at a rate of 20 ml m?3 container volume for 72 h. It accelerated tuber sprouting and increased tuber weight loss. It also caused an increase in the respiration rate, as well as ethylene emission from the tubers during the first 6 days after treatment. The respiration rate of carbon disulphide-treated tubers remained at a higher level than that of untreated controls for 35 days after treatment. In addition, carbon disulphide increased the concentrations of the soluble sugars sucrose and fructose, but not glucose, in the tuber tissues (buds, parenchyma). These findings suggest that carbon disulphide releases potato minitubers from dormancy and that dormancy breakage is associated with changes in tuber metabolism prior to the visible sprouting. 相似文献
65.
Koutsidis G De la Fuente A Dimitriou C Kakoulli A Wedzicha BL Mottram DS 《Journal of agricultural and food chemistry》2008,56(15):6105-6112
The effect of different sugars and glyoxal on the formation of acrylamide in low-moisture starch-based model systems was studied, and kinetic data were obtained. Glucose was more effective than fructose, tagatose, or maltose in acrylamide formation, whereas the importance of glyoxal as a key sugar fragmentation intermediate was confirmed. Glyoxal formation was greater in model systems containing asparagine and glucose rather than fructose. A solid phase microextraction GC-MS method was employed to determine quantitatively the formation of pyrazines in model reaction systems. Substituted pyrazine formation was more evident in model systems containing fructose; however, the unsubstituted homologue, which was the only pyrazine identified in the headspace of glyoxal-asparagine systems, was formed at higher yields when aldoses were used as the reducing sugar. Highly significant correlations were obtained for the relationship between pyrazine and acrylamide formation. The importance of the tautomerization of the asparagine-carbonyl decarboxylated Schiff base in the relative yields of pyrazines and acrylamide is discussed. 相似文献
66.
Suppression of soil-borne pathogens of tomato by composts derived from agro-industrial wastes abundant in Mediterranean regions 总被引：1，自引：0，他引：1
Spyridon Ntougias Kalliope K. Papadopoulou Georgios I. Zervakis Nektarios Kavroulakis Constantinos Ehaliotis 《Biology and Fertility of Soils》2008,44(8):1081-1090
We studied nine composts derived from wastes and by-products of the olive oil, wine, and Agaricus mushroom agro-industries. They were mixed with peat at 1:3 w w
−1 ratios and comparatively evaluated in pot experiments to assess suppressiveness against soil-borne and foliar pathogens of
tomato. All compost amendments demonstrated high levels of suppressiveness against Phytophthora nicotianae Breda de Haan in tomato, when they were applied directly after curing (T0) indicating the occurrence of a “general suppression
phenomenon” (81–100% decrease in plant disease incidence). They were, however, relatively less effective when applied 9 months
after curing (T1, 55–100% disease decrease). Suppressiveness against Fusarium oxysporum f.sp. radicis-lycopersici Jarvis & Shoemaker was relatively lower and varied widely among composts (8–95% and 22–87% decrease in plant disease incidence
for T0 and T1, respectively). Three of the composts conferred induced systemic resistance against the foliar pathogen Septoria lycopersici Speg. Biotic properties were determined, including respiration, fluorescein diacetate hydrolysis, and β-glucosidase activity of composts. The comparative evaluation of the nine composts revealed no shared critical biotic or abiotic
characteristics indicative of their suppressive effects on the soil-borne and foliar pathogens. The complex origin of compost
suppressiveness is discussed and the implementation of individual evaluation of each compost product for a specific use is
advocated. 相似文献
67.
Five soils with different organic matter contents ranging from 0.48 to 10.4% were used to study the adsorption and desorption of alachlor, metolachor, EPTC, chlorothalonil and pirimiphos-methyl in batch experiments. The isotherm shapes according to Giles classification were S-type for alachlor, metolachlor and chlorothalonil, changing to L-type for the latter as the level of soil organic matter increased, and L-type for EPTC and pirimiphos-methyl. The adsorption isotherms fitted the Freundlich equation x/m = KfCe1/n. The Kf values increased with the increase of organic matter content. The amounts of pesticides adsorbed over a range of concentrations of 0.1-20 mg litre-1 reached 63.1% for alachlor, 69.2% for metolachlor, 89.3% for EPTC, 98.4% for chlorothalonil and 96.3% for pirimiphos-methyl. The increase of the amounts desorbed with acetone indicated that the sorption of organic compounds onto organic matter occurred principally via weak London-type induction forces, or dispersion forces which are characteristics of the physical adsorption process. 相似文献
68.
Effect of organic and inorganic fertilizers applied during successive crop seasons on growth and nitrate accumulation in lettuce 总被引：1，自引：0，他引：1
A romaine-type lettuce (Lactuca sativa L.) cv. Corsica was cultivated during three successive crop seasons (late-spring, late-autumn and late-winter) in the same soil of an experimental greenhouse in S.W. Peloponnese, Greece. Seven long-term fertilization treatments were tested for their effect on plant growth and nitrate concentration in the external lettuce leaves. Treatments included: three different doses of organic fertilization (composted sheep manure) applied at the start of each crop season, three different doses of inorganic N fertilization applied via fertigation during each crop season, and a control treatment in which no fertilizer was applied. A drip irrigation system was used to water all plants. The highest nitrate levels were observed in the medium and maximum inorganic fertilization treatments (572–664 mg kg−1) in all crop seasons. They were significantly higher compared to the respective organic fertilization treatments (253–435 mg kg−1) and all other fertilization treatments (148–435 mg kg−1). Crop season affected lettuce growth more than nitrate accumulation in the lettuce leaves: lettuce biomass production was the smallest and most uniform in the late-autumn season and did not respond to the fertilization treatments tested (ranging from 409 to 439 g plant−1), while in the late-spring season biomass production was the highest and most variable (561–841 g plant−1), it correlated with nitrate concentration in the leaves and in the medium and maximum inorganic fertilizer doses it significantly exceeded production from all other fertilization treatments (827–841 g plant−1). Following the three crop seasons the residual availability of N, P and K was clearly enhanced in the soil receiving the organic compared to the inorganic fertilization. Nitrate concentration in lettuce leaves was far below the upper limits set by the European Commission in all fertilization treatments throughout the three crop seasons, a result attributed mainly to the sufficient level of light intensity and duration throughout the year in Southern Greece. 相似文献
69.
Resistance levels and chemical control options of sterile oat (Avena sterilis L.) in Northern Greece
AbstractWhole-plant response experiments in pots and field experiments over two years were conducted to study the resistance levels and chemical control options of sterile oat (Avena sterilis L.) in typical wheat production areas of northern Greece. Data revealed high levels of resistance to the ACCase-inhibiting herbicides clodinafop-propargyl and fenoxaprop-p-ethyl in all sterile oat populations, noticeable levels of resistance of some populations to tralkoxydim and pinoxaden, and high susceptibility of four out of the five populations to the prepackage mixture [mesosulfuron?+?iodosulfuron]. The addition of chlorpyrifos did not improve the efficacy of all herbicides against the resistant populations, implying target-site resistance in the populations tested rather than resistance due to P450-mediated enhanced herbicide metabolism. These results indicated that all populations were at least four times more resistant to clodinafop-propargyl, fenoxaprop-p-ethyl and diclofop-methyl than the susceptible populations, but noticeable levels of resistance of some sterile oat populations to tralkoxydim, pinoxaden and the prepackage mixture [mesosulfuron?+?iodosulfuron] were also recorded. However, viable options for chemical control of this weed still exist. 相似文献
70.
E Boukouvala A Cariani GE Maes RG Sevilla V Verrez-Bagnis M Jérôme I Guarniero G Monios F Tinti FA Volckaert JM Bautista G Krey 《Journal of agricultural and food chemistry》2012,60(32):7941-7948
Overlapping external morphometric characters easily confound the flatfishes Solea aegyptiaca and Solea solea (Soleidae) in areas of the Mediterranean Sea where both species live in sympatry. This leads to uncertainties in the fisheries and marketing of the species, in addition to misinterpretations in biogeography and conservation studies. This paper describes a simple restriction fragment length-based diagnostic test that differentiates S. solea from S. aegyptiaca, as well as from other species of the Soleidae family. Furthermore, the two species living in sympatry in the Gulf of Kavala (North Aegean Sea, Greece) present significant qualitative differences in muscle fatty acid composition, a property that can also be used to distinguish the two cryptic species. 相似文献