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1.
Viability, germination and tube length were investigated in pollen grains of field-grown 'Summerred' apple trees (Malus domestica Borkh) exposed to deionized water, rainfall or simulated acid rain at pH 5.6, 4.0 and 3.0. Pollen viability and germination significantly decreased with lower values of pH and with increasing number of treatments. The effects of pH 5.6 and natural rainfall were not significant. Electron microscope investigation of vegetative pollen cells of plants exposed to acid rain at pH 4.0 and 3.0 showed modified features in mitochondria, plastids and endoplasmic reticulum.  相似文献   

2.
This study was undertaken to validate the “quick, easy, cheap, effective, rugged and safe” (QuEChERS) method using Golden Delicious and Starking Delicious apple matrices spiked at 0.1 maximum residue limit (MRL), 1.0 MRL and 10 MRL levels of the four pesticides (chlorpyrifos, dimethoate, indoxacarb and imidacloprid). For the extraction and cleanup, original QuEChERS method was followed, then the samples were subjected to liquid chromatography-triple quadrupole mass spectrometry (LC-MS/MS) for chromatographic analyses. According to t test, matrix effect was not significant for chlorpyrifos in both sample matrices, but it was significant for dimethoate, indoxacarb and imidacloprid in both sample matrices. Thus, matrix-matched calibration (MC) was used to compensate matrix effect and quantifications were carried out by using MC. The overall recovery of the method was 90.15% with a relative standard deviation of 13.27% (n = 330). Estimated method detection limit of analytes blew the MRLs. Some other parameters of the method validation, such as recovery, precision, accuracy and linearity were found to be within the required ranges.  相似文献   

3.
The fungicide captan (cis-N-((trichloromethyl)thio) 4-cyclo-hexene-1,2-dicarboximide) was applied at the rate of 2.4 g/l to apple trees (c.v. Golden Delicious) individually or as part of a standard treatment program where it was applied eight times during the growing season together with several pesticides. Leaf samples (100 discs of 2.2 cm diameter) were collected from treated and control trees before treatment and at 0, 1, 3, 7, 14, 28, 56, 90 and 112 days after treatment. Fruit samples were taken at mid-season (56 days) and at harvest (112 days). The objective of this study was to determine the captan residue and mutagenicity of leaf and fruit extracts to ascertain the potential health hazard to agricultural workers in these orchards. Surface residues were extracted from leaves and fruits with methylene chloride. These extracts were subsequently analyzed for captan by gas-liquid chromatography (GLC) utilizing an electron-capture detector, and for mutagenicity with two strains (TA98 and TA100) of Salmonella typhimurium, with and without microsomal enzyme activation. Positive mutagenic effects were observed with strain TA100 at 0-14 days post spray, even with extracts from one leaf disc's surface (3.8 cm2) of the single treatment. Captan residues in these samples indicated a decline from 9.3 micrograms/cm2 at 0 days to 0.80 micrograms/cm2 at 14 days and a trace after 112 days. With the standard treatment, in which captan was incorporated eight times in the program starting at the 7-day interval, leaf extracts showed mutagenic activity at 7, 14, 28 and 90 days. Captan residues at these intervals were 11.4, 5.0, 4.1 and 3.4 micrograms/cm2, respectively. Fruit sample extracts of the standard spray were mutagenic to the tester strains TA100 and TA98 both at mid-season and at harvest. Residues of captan on fruits declined from 10.4 micrograms/cm2 at mid-season to 1.1 micrograms/cm2 at harvest. No mutagenic activity was detected with extracts from fruit samples from the single captan application.  相似文献   

4.
Excessive application of lead arsenate pesticides in apple orchards during the early 1900s has led to the accumulation of lead and arsenic in these soils. Lead and arsenic bound to soil humic acids (HA) and soil arsenic species in a western Massachusetts apple orchard was investigated. The metal-humate binding profiles of Pb and As were analyzed with size exclusion chromatography-inductively coupled plasma mass spectrometry (SEC-ICP-MS). It was observed that both Pb and As bind "tightly" to soil HA molar mass fractions. The surface soils of the apple orchard contained a ratio of about 14:1 of water soluble As (V) to As (III), while mono-methyl (MMA) and di-methyl arsenic (DMA) were not detectable. The control soil contained comparatively very low levels of As (III) and As (V). The analysis of soil core samples demonstrated that As (III) and As (V) species are confined to the top 20 cm of the soil.  相似文献   

5.
Open-top chambers (OTCs) and corresponding ambient air plots (AA) were used to assess the impact of ambient ozone on growth of newly planted apple trees at the Montague Field research center in Amherst, MA. Two-year-old apple trees (Malus domestica Borkh 'Rogers Red McIntosh') were planted in the ground in circular plots. Four of the plots were enclosed with OTCs where incoming air was charcoal-filtered (CF); four were enclosed with OTCs where incoming air was not charcoal-filtered (NF) and four were not enclosed, allowing access to ambient air conditions (AA). Conditions in both CF and NF OTCs resulted in increased tree growth and changed incidence of disease and arthropod pests, compared to trees in AA. As a result, we were not able to use the OTC method to assess the impact of ambient ozone on growth of young apple trees in Amherst, MA.  相似文献   

6.
Measurements of the concentrations of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) were made in ambient air, ash, and soil impacted by the open burning of wax apple and rice straw residues. Measurements showed that the mean PCDD/F concentration (0.458 pg I-TEQ/Nm3; international toxicity equivalence) in air at two wax apple orchards during open burning increased markedly, -8.1 times higher than that (0.057 pg I-TEQ/Nm3); before open burning. In addition, the mean PCDD/F concentration (0.409 pg I-TEQ/Nm3) in ambient air at a rice straw field was 4.6 times higher than that (0.089 pg I-TEQ/Nm3) before open burning. After burning the residues of wax apple stubble and rice straw, the contents of PCDD/F in ashes were 1.393 and 1.568 ng I-TEQ/kg-ash, respectively, and the contents of PCDD/F in soil were 2.258 and 2.890 ng I-TEQ/kg-soil, respectively. Therefore, the turnover of soil with the ash after open burning over years will result in the accumulation of PCDD/Fs in farm soils.  相似文献   

7.
Vase-shaped standard apple trees cv. McIntosh were sprayed with azinphos-methyl at pink, pink and 1st cover and 1st cover only. Residue analyses by gas chromatography revealed detectable residues on foliage until mid summer. At harvest, negligible residue levels were found on the peel and the whole apple. On four trees, fluorescein was sprayed in the same manner as the insecticide and maximum levels of the dye were detected on the outside lower canopy along the row. Minimal concentration of fluorescein was detected on the inner upper canopy away from the direction of the row.  相似文献   

8.
Apple orchards are highly manipulated crops in which large amounts of pesticides are used. Some of these pesticides lack target specificity and can cause adverse effects in non-target organisms. In order to evaluate the environmental risk of these products, the use of transplanted sentinel organisms avoids side-effects from past events and facilitate comparison of multiple sites in a short time. We released specimens of the terrestrial snail Xeropicta derbentina in each 5 of two kinds of apple orchards with either conventional or organic management strategies plus in a single abandoned orchard. After one month, individuals were retrieved in order to measure acetylcholinesterase (AChE) activity. Mean values of AChE activity were significantly reduced in all conventional apple orchards compared to the others. Results show that the measurement of biomarkers such as AChE inhibition in transplated X. derbentina could be useful in the environmental risk assessment of post-authorized pesticides.  相似文献   

9.
Environmental Science and Pollution Research - The eddy covariance (EC) technique was used to measure variations of orchard-atmosphere CO2 exchange, as a function of meteorological variables in an...  相似文献   

10.
Propargite, recently introduced in India, is an effective acaricide on a large number of crops most of which are consumed by human beings directly or after processing. Therefore, it has become important to check the dissipation behavior of propargite in edible raw commodities, processed products and in the environment. In the present study, dissipation of residue of this acaricide in soil, apple fruit and tea (green tea leaves, manufactured tea, infusion and spent leaves) was studied. Analysis was carried out using high performance-liquid chromatography with UV detection system. The dissipation rate was found to vary with the nature of studied crop/sample. In soil, half-life ranged from 43 to 45 days, while in plant matrices (tea and apple) it ranged 1.66-2.61 days. The percent transfer of propargite residue from manufactured tea to infusion was 23.60-40.00; however, 35.71-53.20% of the residues remained stuck to the spent leaves.  相似文献   

11.
It is not clear so far whether alteration of leaf micromorphology and surface wax chemistry due to the impact of environmental factors, such as UV-B radiation, affects retention and rainfastness of applied pesticide solutions. In this study; UV-B treated and untreated adaxial leaf surfaces of apple seedlings (Malus domestica Borkh.) were characterized in terms of chemical composition, micromorphological fine structure, hydrophobicity, and wettability. Furthermore, the retention and rainfastness of applied fungicide mancozeb were studied. The samples were examined 0, 24 and 48 h after ultraviolet (UV)-B radiation (0.022 kW m(-2) for 150 min) The total wax mass, recovered from the adaxial leaf surface, amounted from 0.38 microg cm(-2) (control) up to 0.49 microg cm(-2) (24 h). Chemical composition of surface wax altered, whereas the contact angle of applied water droplets on leaf surface of UV-B treated plants did not change significantly compared to the control. The alteration of surface wax quantity and quality significantly affected retention of a.i.; it increased at a sampling time of 24 h after UV-B irradiation, whereas rainfastness of the fungicide spray solution was not significantly influenced.  相似文献   

12.
Azinphos-methyl, carbaryl, dimethoate, phosmet and phosalone were used in apple orchards to manage apple aphid, apple maggot, woolly apple aphid and leaf eating caterpillars. Among the five insecticides evaluated, dimethoate, carbaryl and azinphosmethyl were the most toxic to the nymphs and adults of Hyaliodes vitripennis (Say) from two regions. Phosalone was the least toxic. Nymphs were more resistant than the adults. While the LC50 for dimethoate was 130 ppm for nymphs, it was 3 ppm for adults from St. Jean-Baptiste-de-Rouville. There were also significant differences in the level of resistance between the two regions where the H. vitripennis were collected. At St. Alexandre the LC50 for phosalone on nymphs was 19,250 ppm whereas, at St. Jean-Baptiste-de-Rouville it was 160,000 ppm.  相似文献   

13.
Copper (Cu) desorption and toxicity to the Florida apple snail were investigated from soils obtained from agricultural sites acquired under the Comprehensive Everglades Restoration Plan. Copper concentrations in 11 flooded soils ranged from 5 to 234 mg/kg on day 0 and from 6.2 to 204 mg/kg on day 28 (steady-state). The steady-state Cu concentration in overlying water ranged from 9.1 to 308.2 microg/L. In a 28-d growth study, high mortality in snails occurred within 9 to 16 d in two of three soil treatments tested. Growth of apple snails over 28 d was affected by Cu in these two treatments. Tissue Cu concentrations by day 14 were 12-23-fold higher in snails exposed to the three soil treatments compared to controls. The endangered Florida snail kite and its main food source, the Florida apple snail, may be at risk from Cu exposure in these managed agricultural soil-water ecosystems.  相似文献   

14.
Abstract

Azinphos‐methyl, carbaryl, dimethoate, phosmet and phosalone were used in apple orchards to manage apple aphid, apple maggot, woolly apple aphid and leaf eating caterpillars. Among the five insecticides evaluated, dimethoate, carbaryl and azinphosmethyl were the most toxic to the nymphs and adults of Hyaliodes vitripennis (Say) from two regions. Phosalone was the least toxic. Nymphs were more resistant than the adults. While the LC50 for dimethoate was 130 ppm for nymphs, it was 3 ppm for adults from St. Jean‐Baptiste‐de‐Rouville. There were also significant differences in the level of resistance between the two regions where the H. vitripennis were collected. At St. Alexandre the LC50 for phosalone on nymphs was 19, 250 ppm whereas, at St. Jean‐Baptiste‐de‐Rouville it was 160, 000 ppm.  相似文献   

15.
It is not clear so far whether alteration of leaf micromorphology and surface wax chemistry due to the impact of environmental factors, such as UV-B radiation, affects retention and rainfastness of applied pesticide solutions. In this study; UV-B treated and untreated adaxial leaf surfaces of apple seedlings (Malus domestica Borkh.) were characterized in terms of chemical composition, micromorphological fine structure, hydrophobicity, and wettability. Furthermore, the retention and rainfastness of applied fungicide mancozeb were studied. The samples were examined 0, 24 and 48 h after ultraviolet (UV)-B radiation (0.022 kW m? 2 for 150 min) The total wax mass, recovered from the adaxial leaf surface, amounted from 0.38 μ g cm? 2 (control) up to 0.49 μ g cm? 2 (24 h). Chemical composition of surface wax altered, whereas the contact angle of applied water droplets on leaf surface of UV-B treated plants did not change significantly compared to the control. The alteration of surface wax quantity and quality significantly affected retention of a.i.; it increased at a sampling time of 24 h after UV-B irradiation, whereas rainfastness of the fungicide spray solution was not significantly influenced.  相似文献   

16.
Environmental Science and Pollution Research - The presence of potentially toxic elements (PTEs) in crops can directly/indirectly affect consumers’ health. The contamination of apple as one...  相似文献   

17.
A novel invertebrate embryo test with the apple snail, Marisa cornuarietis, comprising a test protocol for the following developmental endpoints is described: formation of eyes and tentacles, heart rate, hatching, weight after hatching. To evaluate effects on embryonic development, the snails were treated in a first step with 250 or 500 microg/l cadmium. Sublethal effects in terms of a significant delay in hatching could be found in the 250 microg/l treated animals, whereas 500 microg/l Cd were lethal for the snail embryos. To test endocrine disrupting chemicals with this protocol, experiments with bisphenol A (50 microg/l, 100 microg/l) and 17alpha-ethinylestradiol (10 microg/l) were performed. In both treatments an increase of weight after hatching was observed as well as a significant decline in the heart rate of the embryos. As shown here, the sensitivity of M. cornuarietis embryos test is equal or even higher than other test species like zebrafish embryos and, therefore, this test can be regarded as an alternative or supplement for ecotoxicological studies.  相似文献   

18.
Fu J  Wang Y  Zhang A  Zhang Q  Zhao Z  Wang T  Jiang G 《Chemosphere》2011,82(5):648-655
Fengjiang is a large e-waste dismantling site located in southeast China. In this paper, apple snail and soil samples were collected from this e-waste dismantling site and 25 vicinal towns to investigate the contamination status, spatial distributions and congener patterns of polychlorinated biphenyls (PCBs) and polybrominated biphenyl ethers (PBDEs). Total PCB concentrations in apple snails (3.78-1812 ng g−1 dry weight (dw)) were significant higher than that in soil samples (0.48-90.1 ng g−1 dw). PBDE (excluding BDE 209) concentrations in apple snail and soil samples ranged from 0.09 to 27.7 ng g−1 dw and 0.06 to 31.2 ng g−1 dw, respectively. Concentrations of PCBs and PBDEs in snails and soils correlated negatively with the distance from Fengjiang. Both the concentrations and profiles of the pollutants were significantly correlated (p < 0.05) between the snail and soil samples, indicating the suitability of apple snail as a reliable bioindicator for PCBs and PBDEs contamination in this region. Relatively high concentrations of PCBs and PBDEs at locations far from e-waste dismantling sites implied that these pollutants have been transported to surrounding regions.  相似文献   

19.
Environmental Science and Pollution Research - The Loess Plateau is the largest apple cultivation region in the world. However, the role of rain-fed apple orchards as carbon sinks or sources,...  相似文献   

20.
Environmental Science and Pollution Research - The authors analyzed certain species and varieties of fruit tree in which applied crop technology is used and also undergoes the effects of climate...  相似文献   

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