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1.
Investigation on fungicide residues in greenhouse-grown strawberries   总被引：2，自引：0，他引：2  
Maximum residue limits (MRL's) for different agricultural food products in Norway are harmonized with EU standards. In field-grown strawberries in Norway, tolylfluanid has a 7 day quarantine from last application to harvest, while other approved fungicides have 14 days quarantine. Greenhouse production of strawberries is newly introduced to the country. Residue levels in strawberries of the cultivar Korona grown in a commercial greenhouse were investigated 4, 7, and 14 days after application of eight different fungicides at rates recommended by the manufacturers and at half rates. Iprodione, tolylfluanid, and vinclozolin were tested in two experiments, while chinomethionat, chlorothalonil, imazalil, penconazole, and triadimefon were tested once. For chinomethionat, imazalil, iprodione, penconazole, and vinclozolin, the residue levels were below MRL 2 weeks after application. Application of triadimefon in normal rate gave residues below MRL 14 days after application. However, its metabolite, triadimenol, was above MRL at the same time. Tolylfluanid gave very high residue levels, and except from half concentration in the second experiment, all other residue levels were above MRL. Seven days after application, residues in both experiments were approximately 3 times higher than MRL when normal rate of tolylfluanid was applied. For chlorothalonil at the recommended rate, the residue level was above MRL at any sampling time, while half rate gave residues below MRL 14 days after treatment. In view of the present results, tolylfluanid, chlorothalonil, and triadimefon will need longer time from last application to harvest and/or reduced application rates in greenhouse-grown compared to field-grown strawberries. In addition or as an alternative, recommended rates could be lowered.  相似文献   

2.
Residue levels and degradation rates of procymidone residues were studied in green beans grown in a greenhouse. Experiments were planned to also assess the influence of planting density on the behavior of procymidone residues on this type of crop. The study was carried out in four random blocks considering three sub-blocks of different planting densities into each block. Plants were sprayed with Sumisclex 50 WP (1077.5 g of ai/ha) 52 days after the transplantation, and sampling was carried out daily during two different periods of 6 and 5 consecutive days, respectively, around the two harvest days (days 12 and 28 after the treatment). Residue levels of procymidone were determined by using the Luke extraction method and GC-NPD. The average residue levels of procymidone in the overall planting (mean of 12 determinations) were below 2 mg/kg (European maximum residue limit) for all the sampling days, obtaining values of 1.01 +/- 0.55 and 0.37 +/- 0.10 mg/kg, respectively, at the two harvest days. The decline behavior of procymidone residues in the overall plantation and in each block could be described as a pseudo-first-order reaction, obtaining half-life values (t(1/2)) of 10-11 days in all cases. The calculated residue level at the preharvest time (5 days) in the overall plantation was 1.7 mg/kg, but this value in the blocks depended on the block position along the greenhouse and ranged from 2.3 to 0.9 mg/kg. In this work, additional data on the residual behavior of the fungicide pyrazophos in green beans were also obtained.  相似文献   

3.
Residues of azoxystrobin from grapes to raisins   总被引：1，自引：0，他引：1  
Azoxystrobin, a fungicide of the strobilurin group, has an European Union maximum residue level (MRL) of 2 mg/kg for grapes. This work aimed to assess residues on fresh and washed grapes and on raisins following processing with (i) alkali treatment and sun drying and (ii) sun drying only. QUADRIS 25% SC was applied according to good agricultural practice for two consecutive years on a typical cv. Thomson seedless and a seed-producing clone. Samples were collected 0, 15, and 21 days postapplication and analyzed using gas chromatography/electron capture detection; recoveries were 86 +/- 12% for grapes and 99 +/- 15% for raisins. Residues on grapes were 0.49-1.84 mg/kg, and washing removed 75% of the residue. Residues in raisins produced from seedless grapes were 0.51-1.49 (treatment 1) and 1.42-2.08 mg/kg (treatment 2), with residue transfer factors sometimes >1, even following alkali treatment, which reduced residues considerably. To avoid trade problems, a higher MRL for raisins is necessary.  相似文献   

4.
Two fungicides (cyprodinil and fludioxonil) have recently been used in southeast Spain to control disease in lettuce and grape. Gas chromatography with a nitrogen-phosphorus detector (GC-NPD) was used to study the disappearance of these compounds from crops under field conditions and during refrigeration. Residual values 21 days after application were below the maximum residue limit (MRL = 0.05 mg kg(-1)) established by Spanish law in the field experiment for both compounds. However, with the exception of fludioxonil in lettuce, residues were above the MRL in the refrigerated farm produce for both fungicides. The half-lives were 3-6 times greater under refrigeration.  相似文献   

5.
A high-performance liquid chromatography (HPLC) method with ultraviolet (UV) detection was developed for the detection of cefquinome (CEQ) residues in swine tissues. The limit of detection (LOD) of the method was 5 ng g(-1) for muscle and 10 ng g(-1) for fat, liver, and kidney. Mean recoveries of CEQ in all fortified samples at a concentration range of 20-500 ng g(-1) were 80.5-86.0% with coefficient of variation (CV) below 10.3%. Residue depletion study of CEQ in swine was conducted after five intramuscular injections at a dose of 2 mg kg(-1) of body weight with 24 h intervals. CEQ residue concentrations were detected in muscle, fat, liver, and kidney using the HPLC-UV method at 265 nm. The highest CEQ concentration was measured in kidney tissue during the study period, indicating that kidney was the target tissue for CEQ. CEQ concentrations in all examined tissues were below the accepted maximum residue limit (MRL) recommended by the Committee for Veterinary Medical Products of European Medical Evaluation Agency (EMEA) at 3 days post-treatment.  相似文献   

6.
The behavior of the fungicide fenhexamid, N-(2,3-dichloro-4-hydroxyphenyl)-1-methyl-cyclohexanecarboxamide, has been studied at concentrations corresponding to the limits fixed for grapes (3 mg kg(-1)), or higher, during the alcoholic fermentation. The presence of the fungicide did not affect the amount of alcohol produced. The amount of fenhexamid in the liquid phase decreased by ca. 15%, but the missing fenhexamid was recovered unchanged from yeasts. This suggests that the fungicide is not degraded during the fermentation process, but adsorbed by yeasts. Two constituents of Saccharomyces cerevisiae cell wall, chitin and glucan, tested as potential adsorbents, exhibited affinity for fenhexamid.  相似文献   

7.
Chlozolinate (Serinal) is a dicarboximide fungicide used in southern European countries principally on grapes. Maximum residue levels have not yet been set by FAO/WHO and are under evaluation in the EU. Field trials have been carried out in Greece on two varieties of table grapes (Cardinal and Victoria) during two consecutive years to assess residues remaining after application according to good agricultural practice. Analysis using a multiresidue method with gas chromatography (ECD) showed that the parent compound decays with a first-order rate constant of 0.057 +/- 0.011 day(-)(1) and that residues had fallen below the proposed MRL of 5 mg/kg in all samples by 21 days postapplication (the proposed PHI). The contribution of the main metabolite, S1, to the total residue is generally <20%. Washing removes a substantial amount (up to 80%) of chlozolinate, which appears to be nonsystemic on grapes, thus reducing real consumer exposure to this pesticide.  相似文献   

8.
Dissipation of the fungicide spiroxamine in grapes of two vine varieties, Roditis and Cabernet Sauvignon, exposed to field treatments was evaluated. Vines of a grape vineyard located in central Greece were sprayed once or twice with a commercial formulation of the fungicide at 30 g a.i./hL. Residues in grapes, must, and wine were determined by gas chromatography/IT-MS after extraction with cyclohexane-dichloromethane (9:1), with a limit of quantitation 0.02 mg/kg in grapes and 0.012 mg/kg in wine. Under field conditions, spiroxamine dissipation on grapes was faster during the first 2 weeks and then slower to the sixth week. About 7 days after application, half of the initial spiroxamine concentration remained on the grapes; the respective proportion at 42 days was about 10%. At 14 and 35 days, residues were lower than 0.44 and 0.22 mg/kg, respectively, values below the maximum residue levels set by the European Union (1 mg/kg). Spiroxamine residues transferred from grapes into the must and through the vinification process into the wine were also studied. Mean transfer factors of 0.26 and 0.55 were found from grapes into wine for the wines obtained without maceration and with maceration, respectively. Residues in wine, prepared from grapes with a spiroxamine content of 0.11-0.20 mg/kg, varied from <0.026 to 0.09 mg/kg. Spiroxamine diastereomer B was found to dissipate slower than diastereomer A in the field as well as during the vinification process.  相似文献   

9.
The influence of fungicide concentration and treatment temperature on residue levels of pyrimethanil (PYR) in comparison with the commonly used fungicide imazalil (IMZ) was investigated in orange fruits following postharvest dip treatments. The dissipation rate of PYR residues was recorded as a function of storage conditions. The fungicide efficacy against green and blue molds caused by Penicillium digitatum and Penicillium italicum, respectively, was evaluated on different citrus varieties following the fungicide application at 20 or 50 degrees C. Residue levels of PYR in Salustiana oranges were significantly correlated with the fungicide dosage, but residue concentrations were notably higher (ca. 13-19-fold) after treatment at 50 degrees C as compared to treatments at 20 degrees C. After treatment at temperatures ranging from 20 to 60 degrees C, PYR and IMZ residues in Salustiana oranges were significantly correlated with dip temperatures. Dissipation rates of PYR during storage were negligible in both Salustiana and Tarocco oranges. Results obtained on wounded, noninoculated Miho satsumas revealed that when treatments were performed at 50 degrees C, PYR or IMZ concentrations needed to achieve the complete control of decay were 8- and 16-fold less than by treatment at 20 degrees C. When fruits were inoculated with either P. digitatum or P. italicum, the application of 400 mg L(-1) PYR at 20 degrees C or 100 mg L(-1) PYR at 50 degrees C similarly reduced green and blue mold development. These results were corroborated by storage trials on Marsh grapefruits and Tarocco oranges. The lowest concentration of PYR required to achieve almost total protection of the fruit against decay accounted for 100 mg L(-1) at 50 degrees C and 400 mg L(-1) at 20 degrees C, respectively. Treatments did not affect fruit external appearance, flavor, and taste. It is concluded that postharvest PYR treatment represents an effective option to control green and blue mold in citrus fruit and that integration of fungicide applications and hot water dips may reduce the possibility of selecting fungicide-resistant populations of the pathogen, as a consequence of increased effectiveness of the treatment.  相似文献   

10.
Mature apricots (Prunus armeniaca), nectarines [Prunus persica var. nectarine (Ait.)], and peaches [P. persica (L.) Batsch.] were subjected to a 2 min dip treatment with warm water at 48 degrees C or with fludioxonil (FLU) at 100 mg L-1 and 20 degrees C or at 25 mg L-1 FLU and 48 degrees C and then stored at 5 degrees C and 90-95% relative humidity (RH) for 1 week plus 1 additional week at 18 degrees C and approximately 80% RH. Fruit residue uptake was determined as a function of fungicide concentration, dip temperature, treatment time (only on nectarines), and fruit storage conditions. FLU residue level was closely related to fungicide concentration and treatment temperatures and was dependent on fruit species. FLU residues showed great persistence over both storage and shelf life. Fruit dipping in water at 48 degrees C effectively reduced decay development in cvs. 'May Grand' nectarines and 'Pelese' apricots but was ineffective in cvs. 'Red Top' and 'Sun Crest' nectarines during 7 days of storage compared with nontreated fruit. Decay rates in cvs. 'Glo Haven' peaches and 'Fracasso' apricots were very low in fruit dipped in water at both 20 and 48 degrees C. Fungicide treatments at 20 and 48 degrees C resulted in the total or almost total suppression of decay in all cultivars. During shelf life, fruit became very prone to decay, averaging 25.7-100% depending on the cultivar. Fruit dipping in hot water effectively reduced decay in 'Pelese' and 'Fracasso' apricots, 'Sun Crest' peaches, and 'May Grand' nectarines as compared to control, but was ineffective in 'Glo Haven' and 'Red Top' peaches. Fungicide treatments at 20 degrees C were more effective than hot water in most cultivars. The combination of FLU with water at 48 degrees C further improved the fungicide performance. Indeed, reduced levels (a fourth) of active ingredient were required to achieve a control of decay comparable to that for treatment at 20 degrees C. Residue levels in fruit after treatment with 100 mg L-1 FLU at 20 degrees C or with 25 mg L-1 FLU at 48 degrees C averaged approximately 0.6-2 mg kg-1, which were notably lower than the maximum residue limit (5 mg kg-1) allowed in the United States for stone fruit.  相似文献   

11.
The disappearance of azoxystrobin, pyrimethanil, cyprodinil, and fludioxonil on tomatoes in greenhouse was studied. At the preharvest interval, except for cyprodinil, the pesticide residues were below the MRL fixed in Italy. The mechanism of disappearance studied with model systems shows that the decrease in residues was due to codistillation and photodegradation in pyrimethanil, to photodegradation in fludioxonil, and to evaporation and codistillation in cyprodinil. Azoxystrobin residues were stable during all experiments.  相似文献   

12.
Strobilurin fungicides have been increasingly used for fungus pest control since they were introduced in 1996. For pesticide residue detection, immunoassays constitute nowadays a valuable approach. This paper describes the synthesis of functionalized haptens of kresoxim-methyl, the production of monoclonal antibodies, and the development of enzyme-linked immunosorbent assays. On the one hand, a two-step conjugate-coated immunoassay was optimized using extended or short incubation times, with limits of detection of 0.4 ng/mL for the extended assay and 0.3 ng/mL for the rapid assay. On the other hand, an immunoassay was optimized following a procedure consisting of just one incubation step. This one-step assay had a limit of detection of 0.4 ng/mL. All of these assays showed a similar performance, with sensitivities well below common maximum residue limits for this pesticide (50 microg/kg) and lower than the detection limits of the usual chromatographic detection methods.  相似文献   

13.
The effects of six clarification agents (egg albumin, blood albumin, bentonite plus gelatin, charcoal, PVPP, and silica gel) on the removal of residues of four fungicides (cyprodinil, fludioxonil, pyrimethanil, and quinoxyfen) applied directly to a racked red wine, elaborated from Monastrell variety grapes from the D.O. region of Jumilla (Murcia, Spain), are studied. The clarified wines were filtered with 0.45 microm nylon filters to determine the influence of this winemaking process in the disappearance of fungicide residues. Analytical determination of cyprodinil, fludioxonil and pyrimethanil was performed by gas chromatography with an alkaline thermoionic detector (NPD), whereas that of quinoxyfen using an electron captor detector (ECD). In general, and for all of the fungicides except quinoxyfen, blood albumin has proved to be the most effective clarifying agent in the removal of residues, whereas silica gel proved to be ineffective against all of the pesticides with the exception of fludioxonil. Quinoxyfen is the least persistent fungicide in the clarified wines and that which appears with highest frequency in the lees. In general, filtration is not an effective step in the elimination of wine residues. The greatest elimination after filtration is obtained in wines clarified with charcoal and the lowest in those clarified with PVPP.  相似文献   

14.
Residues of the fungicides vinclozolin and procymidone, used to control the Botrytis cinerea disease, were studied in greenhouse grown lettuce, tomato and cucumber. Residue concentrations differed between the species of treated vegetables, and depended mostly on time of picking (harvest), size of fruits and mode of chemical application. The differences in concentration between one and two applications became smaller with time after application. The greatest differences occurred in lettuce. The residue contents in cucumber fruits assigned both for industrial and home processing (pickling) were higher than the legal limit (3 mg/kg). As a result of washing cucumbers, 22–24% of the residue was eliminated, and by peeling them 79–85% of the vinclozolin and procymidone residues were eliminated. Therefore it is reasonable that one or two applications of these fungicides should be used, with a time lapse of 14 days, but only with cucumbers intended for salad consumption. Vinclozolin residues, when used as vaporisation tablets, were in all cases 35–65% lower compared with the wettable powder (WP) formulation; however, the rate of of residue decrease was much slower. When applied in the form of vaporable tablets, the vinclozolin residue concentration was lower in all the sampled fruits in comparison with the WP formulation. The concentration of fungicide residues detected in winter tomato fruits was higher than that of the spring crop. Irrespective of vegetable the detected levels of fungicide residues were lower in ripe and bigger fruits than in green and smaller ones.  相似文献   

15.
A rapid, specific, and sensitive method based on the Quick Easy Cheap Effective Rugged and Safe (QuEChERS) method and a cleanup using dispersive solid-phase extraction with MgSO(4), PSA, and C18 sorbents has been developed for the routine analysis of 14 pesticides in strawberries. The analyses were performed by three different analytical methodologies: gas chromatography (GC) with electron capture detection (ECD), mass spectrometry (MS), and tandem mass spectrometry (MS/MS). The recoveries for all the pesticides studied were from 46 to 128%, with relative standard deviation of <15% in the concentration range of 0.005-0.250 mg/kg. The limit of detection (LOD) for all compounds met maximum residue limits (MRL) accepted in Portugal for organochlorine pesticides (OCP). A survey study of strawberries produced in Portugal in the years 2009-2010 obtained from organic farming (OF) and integrated pest management (IPM) was developed. Lindane and β-endosulfan were detected above the MRL in OF and IPM. Other OCP (aldrin, o,p'-DDT and their metabolites, and methoxychlor) were found below the MRL. The OCP residues detected decreased from 2009 to 2010. The QuEChERS method was successfully applied to the analysis of strawberry samples.  相似文献   

16.
采用高效液相色谱（HPLC）分析方法,研究了多菌灵在草莓与土壤中的消解动态和最终残留。分析结果表明,多菌灵最低检出浓度为0.05 mg.kg-1,添加浓度在0.05～2.0 mg.kg-1范围内,回收率为81.6%～102.6%,变异系数为1.44%～5.35%。田间试验结果表明,多菌灵推荐浓度和加倍浓度在草莓中的消解动态方程分别为C=3.212 2e-0.1354t、C=8.810 3e-0.1379t,土壤中的消解动态方程分别为C=2.941 1e-0.1011t、C=6.173 3e-0.1144t。多菌灵消解较快,草莓中的消解半衰期为4.2～6.7 d,土壤中的消解半衰期为5.4～7.3 d。加倍浓度和推荐浓度各施药2次,30 d后残留量均降至0.1 mg.kg-1以下,低于多菌灵在果蔬中最大允许残留量（MRL）0.5 mg.kg-1。  相似文献   

17.
Nematicides are widely used to control plant-parasitic nematodes in intensive export banana (Musa spp.) cropping systems. Data show that the concentration of fosthiazate in banana fruits varies from zero to 0.035 g kg-1, under the maximal residue limit (MRL=0.05 mg kg-1). The fosthiazate concentration in fruit is described by a Gaussian envelope curve function of the interval between pesticide application and fruit harvest (preharvest interval). The heterogeneity of phenological stages in a banana population increases over time, and thus the preharvest interval of fruits harvested after a pesticide application varies over time. A phenological model was used to simulate the long-term harvest dynamics of banana at field scale. Simulations show that the mean fosthiazate concentration in fruits varies according to nematicide application program, climate (temperature), and planting date of the banana field. This method is used to assess the percentage of harvested bunches that exceed a residue threshold and to help farmers minimize fosthiazate residues in bananas.  相似文献   

18.
The effects of three fungicide residues (cyprodinil, fludioxonil, and pyrimethanil) on the aromatic composition (acids, alcohols, and esters) of Vitis vinifera white wines (var. Airén) inoculated with three Saccharomyces cerevisiae strains (syn. bayanus, cerevisiae, and syn. uvarum) are studied. The aromatic exponents were extracted and concentrated by adsorption-thermal desorption and were determined by gas chromatography using a mass selective detector. The addition of the three fungicides at different doses (1 and 5 mg/L) produces significant differences in the acidic fraction of the aroma, especially in the assays inoculated with S. cerevisiae, although the final contents do not exceed the perception thresholds. The lower quality wines, according to isomeric alcohol content [(Z)-3-hexen-1-ol and 3-(methylthio)propan-1-ol] are those obtained by inoculation with S. cerevisiae(syn. bayanus) and addition of cyprodinil. The addition of fungicides in the assays inoculated with S. cerevisiae (syn. bayanus) produces an increase in the ethyl acetate and isoamyl acetate contents, which causes a decrease in the sensorial quality of the wine obtained.  相似文献   

19.
Pesticide residues in grapes, wine, and their processing products   总被引：10，自引：0，他引：10  
In this review the results obtained in the 1990s from research on the behavior of pesticide residues on grapes, from treatment to harvest, and their fate in drying, wine-making, and alcoholic beverage processing are reported. The fungicide residues on grapes (cyproconazole, hexaconazole, kresoxim-methyl, myclobutanil, penconazole, tetraconazole, and triadimenol), the application rates of which were of a few tens of grams per hectare, were very low after treatment and were not detectable at harvest. Pyrimethanil residues were constant up to harvest, whereas fluazinam, cyprodinil, mepanipyrim, azoxystrobin, and fludioxonil showed different disappearance rates (t(1/2) = 4.3, 12, 12.8, 15.2, and 24 days, respectively). The decay rate of the organophosphorus insecticides was very fast with t(1/2) ranging between 0.97 and 3.84 days. The drying process determined a fruit concentration of 4 times. Despite this, the residue levels of benalaxyl, phosalone, metalaxyl, and procymidone on sun-dried grapes equalled those on the fresh grape, whereas they were higher for iprodione (1.6 times) and lower for vinclozolin and dimethoate (one-third and one-fifth, respectively). In the oven-drying process, benalaxyl, metalaxyl, and vinclozolin showed the same residue value in the fresh and dried fruit, whereas iprodione and procymidone resides were lower in raisins than in the fresh fruit. The wine-making process begins with the pressing of grapes. From this moment onward, because the pesticide on the grape surface comes into contact with the must, it is in a biphasic system, made up of a liquid phase (the must) and a solid phase (cake and lees), and will be apportioned between the two phases. The new fungicides have shown no effect on alcoholic or malolactic fermentation. In some cases the presence of pesticides has also stimulated the yeasts, especially Kloeckera apiculata, to produce more alcohol. After fermentation, pesticide residues in wine were always smaller than those on the grapes and in the must, except for those pesticides that did not have a preferential partition between liquid and solid phase (azoxystrobin, dimethoate, and pyrimethanil) and were present in wine at the same concentration as on the grapes. In some cases (mepanipyrim, fluazinam, and chlorpyrifos) no detectable residues were found in the wines at the end of fermentation. From a comparison of residues in wine obtained by vinification with and without skins, it can be seen that their values were generally not different. Among the clarifying substances commonly used in wine (bentonite, charcoal, gelatin, polyvinylpolypyrrolidone, potassium caseinate, and colloidal silicon dioxide), charcoal allowed the complete elimination of most pesticides, especially at low levels, whereas the other clarifying substances were ineffective. Wine and its byproducts (cake and lees) are used in the industry to produce alcohol and alcoholic beverages. Fenthion, quinalphos, and vinclozolin pass into the distillate from the lees only if present at very high concentrations, but with a very low transfer percantage (2, 1, and 0.1%, respectively). No residue passed from the cake into the distillate, whereas fenthion and vinclozolin pass from the wine, but only at low transfer percentages (13 and 5%, respectively).  相似文献   

20.
Copper fungicide residues in Australian vineyard soils   总被引：2，自引：0，他引：2  
Copper (Cu) concentrations were measured in Australian vineyard soils to assess the extent and magnitude of Cu accumulation resulting from the use of Cu-based fungicides and to indicate the likely risks to long-term soil fertility. Soil samples were collected from 98 vineyards across 10 grape-growing regions of Australia and analyzed for total Cu concentrations. Ninety-six percent of vineyards surveyed had elevated Cu concentrations in soil compared to the background Cu concentrations in nearby soil in its native state. Concentrations of total B, Co, Cr, Pb, and Zn were similar to background concentrations and below reported toxicity guideline values. Cu concentrations in Australian vineyard soils were generally much lower (6-150 mg kg (-1)) than those reported in the soils of vineyards in parts of Europe (i.e., 130-1280 mg kg (-1)). Concentrations of total Cu were generally below those concentrations reported to cause lethal effects to soil invertebrates; however, Cu exceeded concentrations known to cause sublethal effects (i.e., inhibit growth, affect reproduction, induce avoidance behavior) to those (or related) invertebrates.  相似文献   

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