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Attempt of using peach plant antioxidant system elements changes as a test-factor of acid stress
2002
Klymenko, O.E. | Klymenko, M.I. (Nikita Botanical Gardens UAAS, Simferopol (Ukraine). Steppe Department)
It was established the strong changes in elements of antioxidation system by the influence of acid stress. The different reaction of varieties in these conditions was discovered. More early ripening varieties were more sensitive to acid stress. The relative indexes of plant antioxidation system conditions were calculated. The relative evaluation of the sensitivity of studied varieties to the acid stress was done by those indexes. We propose to use index of common recovering activity of tissue as a test index for the estimation of different peach varieties to acid stress
اظهر المزيد [+] اقل [-]Fluorine in vegetation due to an uncontrolled release of gaseous fluorides from a glassworks: A case study of measurement uncertainty, dispersion pattern and compliance with regulation
2019
Štepec, Dona | Tavčar, Gašper | Ponikvar-Svet, Maja
This study was initiated after the appearance of chlorotic and necrotic lesions on vegetation in the vicinity of a glassworks. The aim was to establish whether the cause was an uncontrolled release of gaseous fluorides. Five different plant species (Norway spruce, peach, common hornbeam, common bean, common grape vine) were collected in the influenced area, and the fluorine (F) content was determined by a fluoride ion selective electrode after prior total sample decomposition by alkaline carbonate fusion. The measurement results were reported together with their measurement uncertainties (MUs), which were evaluated according to the Guide to the Expression of Uncertainty in Measurement. The F contents at comparable distances from the emitter and in a clean area, free from natural or anthropogenic fluoride emissions, were 87–676 and 10 μg g⁻¹, respectively, thereby confirming the release of gaseous fluorides from the glassworks. The F contents in samples of Norway spruce taken at various radial distances from the emitter suggest that the emitted gaseous fluorides were spread about evenly in all directions from the source following an inverse-power function. Estimated distances at which the F content would decrease to 50 μg g⁻¹ (allowed maximum content of F in feeding stuffs) and 21 μg g⁻¹ (maximum fluoride content in vegetables and fruits in relation to the upper limit of fluoride intake for humans) were 378 m and 571 m, respectively, from the emitter. Evaluation of our results for compliance with specification revealed a lack of regulation on fluoride content in the diet of humans and animals as well as a lack of guidelines on how to take into account MU.
اظهر المزيد [+] اقل [-]Differential responses of peach (Prunus persica) seedlings to elevated ozone are related with leaf mass per area, antioxidant enzymes activity rather than stomatal conductance
2017
Dai, Lulu | Li, Pin | Shang, Bo | Liu, Shuo | Yang, Aizhen | Wang, Younian | Feng, Zhaozhong
To evaluate the ozone (O3) sensitivity among peach tree (Prunus persica) cultivars widely planted in Beijing region and explore the possible eco-physiological response mechanisms, thirteen cultivars of peach seedlings were exposed to either charcoal-filtered air or elevated O3 (E-O3, non-filtered ambient air plus 60 ppb) for one growing season in open-top chambers. Leaf structure, stomatal structure, gas exchange and chlorophyll a fluorescence, photosynthetic pigments, antioxidant defense system and lipid peroxidation were measured in three replicated chambers. Results showed that E-O3 significantly reduced abaxial epidemis thickness, but no effects on the thicknesses of adaxial epidemis, palisade parenchyma and spongy parenchyma. Stomatal area, density and conductance were not significantly affected by E-O3. E-O3 significantly accelerated leaf senescence, as indicated by increased lipid peroxidation and more declines in light-saturated photosynthetic rate and pigments contents. The reduced ascorbate content (ASC) was decreased but antioxidant enzyme activity (CAT, APX and SOD) and total antioxidant capacity (TAC) were significantly increased by E-O3 among cultivars. The cultivars with visible symptoms also had more reductions in net photosynthetic rate than those without visible symptoms. Ozone sensitivity among cultivars was strongly linked to leaf mass per area (LMA), antioxidant enzymes activity e.g. SOD, APX rather than stomatal parameters (stomatal area, density and conductance) and ASC. Results could provide a theoretical basis for selecting and breeding the ozone-resistant cultivars of peach trees grown in high O3-polluted regions.
اظهر المزيد [+] اقل [-]Integrating life cycle assessment and a farmer survey of management practices to study environmental impacts of peach production in Beijing, China
2022
Li, Ziyue | Chen, Yongliang | Meng, Fanlei | Shao, Qi | Heal, Mathew R. | Ren, Fengling | Tang, Aohan | Wu, Jiechen | Liu, Xuejun | Cui, Zhenling | Xu, Wen
While intensive peach production has expanded rapidly in recent years, few studies have explored the environmental impacts associated with specific regional systems or the optimal management strategies to minimize associated environmental risks. Here, data from a survey of 290 native farmers were used to conduct a life cycle assessment to quantify the acidification potential (AP), global warming potential (GWP), eutrophication potential (EP), and reactive nitrogen (Nr) losses in peach production in Pinggu District, Beijing. Total annual Nr losses, and GWP, AP, and EP values for peach production in Pinggu District were respectively 10.7 kg N t⁻¹, 857 kg CO₂-eq t⁻¹, 12.9 kg SO₂-eq t⁻¹, and 4.1 kg PO₄-eq t⁻¹. The principal driving factors were fertilizer production, transportation, and application, which together accounted for 94%, 67%, 75%, and 94% of Nr losses, GWP, AP, and EP, respectively. In the high yield, high nitrogen-use efficiency (HH) group, relative values of Nr losses, GWP, AP, and EP were respectively 33%, 25%, 39%, and 32% lower than the overall averages for 290 orchards. Further analyses indicate that improved farming practices such as decreasing application rates of fertilizers, increasing proportion of base fertilization rate, and proper fertilization frequency in the HH group were the main reasons for these orchards’ better performance in peach yields and partial factor productivity of nitrogen fertilizer, and their reduced environmental impacts. These results highlight the need to optimize nutrient management in peach production in order simultaneously to realize both environmental sustainability and high productivity in the peach production system.
اظهر المزيد [+] اقل [-]Levels of pesticide residues in fruits and vegetables in the Turkish domestic markets
2021
Toptanci, İsra | Kiralan, Mustafa | Ramadan, Mohamed Fawzy
In this work, pesticide residues in 493 fruit and vegetable samples obtained from markets in Turkey were detected after QuEChERS (quick, easy, cheap, effective, rugged, and safe) extraction followed by liquid chromatography-tandem mass spectrometry with electron spray ionization (LC-ESI/MS/MS) and gas chromatography-tandem mass spectrometry (GC/MS/MS). Validation of the method was tested based on the European Union SANTE/12682/2019 guidelines. The samples were analyzed to determine the concentrations of 500 pesticide residues. The results indicated that 254 samples of 493 samples contaminated with pesticides, only 22% contained pesticide residues at or below maximum residue limits (MRLs), and 30% contained pesticide residues above MRLs. Chlorpyrifos was the most common pesticide (105 samples) from the detected pesticides; 49 samples were found above to MRLs with concentrations of 0.011–2.001 mg/kg. Among samples, peach (88%), dill (84%), mushroom (83%), arugula (73%), and spinach (72%) were the crops with the higher percentages of pesticide residues.
اظهر المزيد [+] اقل [-]Conversion of peach endocarp and polyethylene residue by the co-pyrolysis process
2022
Valadão, Lidiane Schmalfuss | dos Santos Duarte, Caroline | de los Santos, Diego Gil | Filho, Pedro José Sanches
The south of Brazil has a high production of peaches which generates the stone as residue. The recycling of biomass and plastic waste is a challenge that must be overcome. Therefore, co-pyrolysis emerges as a possibility for joint conversion of peach stone and plastic bags into value-added products. Thus, the objective is to obtain new products, emphasizing the organic fraction of the bio-oil obtained under the best experimental conditions, and to characterize it by GC-MS. The experiments provided a three-phase bio-oil: two organic phases with different densities and an aqueous phase. It was observed that the central point experiment (temperature at 500 °C and blend composition, % peach stone/polyethylene, 80/20) generated the highest yield of bio-oil. However, the experiment at the lowest temperature and with greater addition of plastic waste produced a higher organic fraction. Using gas chromatography, 161 chemical compounds were identified in the denser organic phase, emphasizing the phenols. In the lighter organic fraction, hydrocarbons were the majority among the 70 compounds identified. The results suggest that the interaction between biomass and polyethylene influences the characteristics of the products obtained, since polyethylene acts as dispersant and as hydrogen donor. Co-pyrolysis, in this research, proves to be efficient and viable, allowing the joint destination of those environmental liabilities.
اظهر المزيد [+] اقل [-]Pesticide residues in fruit samples: comparison of different QuEChERS methods using liquid chromatography–tandem mass spectrometry
2015
Christia, C. | Bizani, E. | Christophoridis, C. | Fytianos, K.
Acetate- and citrate-buffered quick, easy, cheap, effective, rugged, safe (QuEChERS) pretreatment methods were evaluated for the determination of various pesticides in peaches, grapes, apples, bananas, pears, and strawberries from various regions of Greece, using LC-MS/MS. The purposes of this study were (i) to evaluate which type of QuEChERS method was the most appropriate and effective for each matrix; (ii) to apply the selected QuEChERS method for each matrix, in order to detect and quantify pesticide residues in various fruit samples using UPLC-MS/MS; (iii) to examine the concentration distribution of pesticide classes among fruit originating from various areas; and (iv) to assess pesticide concentration distribution between peel and flesh of fruit in order to evaluate the penetration of pesticide residues in the fruit flesh. Acetate-buffered QuEChERS was found to be the most suitable technique for most of the fruit matrices. According to the recovery values at two different concentration levels, peaches should preferably be treated by the citrate-buffered type, whereas grapes, bananas, apples, pears, and strawberries are best treated by the acetate-buffered version, although the differences in efficiency were small. The addition of graphitized carbon black significantly decreases the recovery of specific pesticides in all matrices except for strawberries. The majority of values do not exceed the official maximum residue levels set by the European Commission. Organophosphates proved to be the most commonly detected category along with triazines-triazoles-conazoles group and by carbamates. Apples and pears seem to be the most contaminated fruit matrices among those tested. Distribution of pesticide classes shows variations between different regions, suggesting different pesticide application practices. In the case of peaches and pears, there is an equal distribution of detected pesticides between peel and flesh, indicating penetration of contaminants into the fruit flesh.
اظهر المزيد [+] اقل [-]Effects of monoterpenes on mortality, growth, fecundity, and ovarian development of Bactrocera zonata (Saunders) (Diptera: Tephritidae)
2018
El-Minshawy, AbdelazizM. | Abdelgaleil, SamirA. M. | Gadelhak, GadelhakG. | AL-Eryan, MohamedA. | Rabab, RafiaaA.
The peach fruit fly (PFF), Bactrocera zonata, is a serious insect pest infesting fruits and vegetables. The insecticidal activity of three monoterpenes, namely, (R)-camphor, (R)-carvone, and (1R,2S,5R)-menthol, was evaluated on the second-instar larvae of B. zonata. In addition, the latent effects of monoterpenes on pupation, adult emergence, deformation, oviposition, adult longevity, and ovarian development were also examined. The three tested monoterpenes showed pronounced insecticidal activity against B. zonata larvae with (R)-carvone being the most potent toxicant. When the second-instar larvae of B. zonata were treated with monoterpenes at concentrations of 20, 50, and 70 mg/kg for 72 h, significant reduction in pupation and adult emergence was observed. The three monoterpenes caused complete suppression of adult emergence at 100 mg/kg. Moreover, monoterpenes induced complete inhibition of egg deposition at all tested concentrations. Some adult deformations were also noticed at 20, 50, and 70 mg/kg. However, (R)-carvone was more effective than (1R,2S,5R)-menthol and (R)-camphor on the examined biological parameters. On the other hand, histological examination of the ovaries of emerged females from larvae that fed on diet treated with (R)-carvone, (1R,2S,5R)-menthol, and (R)-camphor at 20 and 50 mg/L indicated that both concentrations caused retardation in the development of ovarioles. It is clear that all the egg chambers are empty; the germarium region is constricted at base due to the failure of oocyte formation. Many vacant spaces were present between ovarioles.
اظهر المزيد [+] اقل [-]Farm and product carbon footprints of China’s fruit production—life cycle inventory of representative orchards of five major fruits
2016
Yan, Ming | Cheng, Kun | Yue, Qian | Yan, Yu | Rees, R. M. (Robert M.) | Pan, Genxing
Understanding the environmental impacts of fruit production will provide fundamental information for policy making of fruit consumption and marketing. This study aims to characterize the carbon footprints of China’s fruit production and to figure out the key greenhouse gas emissions to cut with improved orchard management. Yearly input data of materials and energy in a full life cycle from material production to fruit harvest were obtained via field visits to orchards of five typical fruit types from selected areas of China. Carbon footprint (CF) was assessed with quantifying the greenhouse gas emissions associated with the individual inputs. Farm and product CFs were respectively predicted in terms of land use and of fresh fruit yield. Additionally, product CFs scaled by fruit nutrition value (vitamin C (Vc) content) and by the economic benefit from fruit production were also evaluated. The estimated farm CF ranged from 2.9 to 12.8 t CO₂-eq ha⁻¹ across the surveyed orchards, whereas the product CF ranged from 0.07 to 0.7 kg CO₂-eq kg⁻¹ fruit. While the mean product CFs of orange and pear were significantly lower than those of apple, banana, and peach, the nutrition-scaled CF of orange (0.5 kg CO₂-eq g⁻¹ Vc on average) was significantly lower than others (3.0–5.9 kg CO₂-eq g⁻¹ Vc). The income-scaled CF of orange and pear (1.20 and 1.01 kg CO₂-eq USD⁻¹, respectively) was higher than apple, banana, and peach (0.87~0.39 kg CO₂-eq USD⁻¹). Among the inputs, synthetic nitrogen fertilizer contributed by over 50 % to the total greenhouse gas (GHG) emissions, varying among the fruit types. There were some tradeoffs in product CFs between fruit nutrition value and fruit growers’ income. Low carbon production and consumption policy and marketing mechanism should be developed to cut down carbon emissions from fruit production sector, with balancing the nutrition value, producer’s income, and climate change mitigation.
اظهر المزيد [+] اقل [-]Peach leaf responses to soil and cement dust pollution
2015
Maletsika, Persefoni A. | Nanos, George D. | Stavroulakis, George G.
Dust pollution can negatively affect plant productivity in hot, dry and with high irradiance areas during summer. Soil or cement dust were applied on peach trees growing in a Mediterranean area with the above climatic characteristics. Soil and cement dust accumulation onto the leaves decreased the photosynthetically active radiation (PAR) available to the leaves without causing any shade effect. Soil and mainly cement dust deposition onto the leaves decreased stomatal conductance, photosynthetic and transpiration rates, and water use efficiency due possibly to stomatal blockage and other leaf cellular effects. In early autumn, rain events removed soil dust and leaf functions partly recovered, while cement dust created a crust partially remaining onto the leaves and causing more permanent stress. Leaf characteristics were differentially affected by the two dusts studied due to their different hydraulic properties. Leaf total chlorophyll decreased and total phenol content increased with dust accumulation late in the summer compared to control leaves due to intense oxidative stress. The two dusts did not cause serious metal imbalances to the leaves, except of lower leaf K content.
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