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1.
Residues of the pesticides chlorpyrifos, dimethoate, cyhalothrin, cypermethrin, fenvalerate, deltamethrin and chlorothalonil in the autumn Chinese cabbage (Brassica chinensis L.) were studied using gas chromatography. The results indicated that the residues were dependent on the frequency and rate of pesticide application and on the weather conditions immediately following spraying. When the Chinese cabbages were treated once at normal rates, the half-lives of the seven pesticides in the vegetable were 4.7, 5.3, 2.9, 3.5, 5.4, 4.3 and 4.0 days respectively. Thus, based on the recommended preharvest intervals, the residual levels of all pesticides were within the national standards. When the Chinese cabbages were treated four times at maximal rates at 5 day intervals, the half-lives of chlorpyrifos, cypermethrin and chlorothalonil in the vegetable were 3.6, 2.9 and 5.9 days respectively, so that, based on the recommended preharvest intervals, the residual levels of chlorpyrifos and chlorothalonil exceeded the national standards for pollution-free vegetables, but the residual level of cypermethrin was within the national standard. Effects of rain on pesticide final residues in plants treated four times were more significant than in those treated once. 相似文献
2.
几种农药在露地黄瓜上的残留降解动态检测研究 总被引：2，自引：0，他引：2
研究了在露地黄瓜栽培中。喷施毒死蜱、甲氰菊酯、氯氰菊酯、吡虫啉、百菌清、甲基硫菌灵和王铜等农药的残留降解动态。结果表明，不同农药在黄瓜果实中的残留量和降解速度有很大差异。在杀虫剂中．甲氰菊酯在喷药后第1d的残留量最大，其后的降解速度较快；毒死蜱残留量位居第二，其降解速度比较稳定；氯氰菊酯在喷药后第1d的残留量超过标准．但第3d以后就检测不到其残留：吡虫啉在施药后第1d的残留量最低，降解速度也比较稳定。在杀菌剂中．甲基硫菌灵的降解速度较快，百菌清和王铜的降解速度较慢。无论是杀虫剂还是杀菌剂，施药后在黄瓜上的残留量随喷药时间的推移而减少。 相似文献
3.
BACKGROUND: The composition and properties of a biomixture used in a biobed are decisive for pesticide sorption and degradation. This study was performed to investigate the capability of compost‐based substrates in mixtures with citrus peel and vine branch straw and peat‐based substrates in mixtures with soil and vine branch straw at different levels in order to degrade isoproturon and bentazone. RESULTS: Dissipation and mineralisation rates of both pesticides were determined, and metabolic activity was followed as respiration. Compost‐based substrates showed faster pesticide dissipation in the presence of lignocellulosic materials, as in garden compost and vine branch straw. The increasing content of vine branch straw in peat‐based substrates does not seem to affect dissipation of the parent compounds. Low mineralisation rate was observed in all treatments. CONCLUSION: Higher pesticide degradation was observed in the lignocellulosic substrates, probably because of the development of lignin‐degrading microorganisms which have shown to be robust and are able to degrade recalcitrant pesticides. Copyright © 2010 Society of Chemical Industry 相似文献
4.
高尔夫球场农药向大气中的挥发研究 总被引：1，自引：0，他引：1
高尔夫球场喷洒农药向大气中的挥发受农药性质、施药方式和环境条件的影响。用丙酮、二氯甲烷等有机溶剂作吸收液可较好地捕集空气中的氯氰菊酯、毒死蜱、百茵清等农药化合物。试验条件下,2,4-D丁酯、百菌清和氯氰菊酯在大气中的挥发损失率分别为6．31％、1.38％、7．20％,毒死蜱和灭多威的挥发损失率为0．78％和1．66％。相比之下,氯氰菊酯较易挥发,对空气的污染较大。选择性用药,采用颗粒剂撒施,可有效地减少农药挥发,有利于环境保护。 相似文献
5.
臭氧水对黄瓜和青菜中6种有机磷农药残留的去除效果 总被引：2，自引：0，他引：2
考察了臭氧水浸泡处理对黄瓜和青菜上6种有机磷类农药残留的去除效果。发现臭氧水浸泡的去除效果优于自来水处理,在通臭氧30 min后,其对青菜和黄瓜中乙酰甲胺磷、二嗪磷、马拉硫磷、毒死蜱、喹硫磷和三唑磷的总去除率分别为26.4%~65.2%和22.7%~75.4%,净去除率分别为6.8%~17.3%和4.4%~45.4%。对6种农药在臭氧水中降解速率的研究表明,臭氧处理对残留农药的去除效果与果蔬种类、处理时间及残留物种类有关。 相似文献
6.
Adnan I. Al-Samariee Khloud A. M. Shaker Mabrouk A. Al-Bassomy 《Pest management science》1988,22(3):189-194
The degradation rates and residue levels of diazinon, pirimiphos-methyl and chlorpyrifos in the leaves and fruits of pepper plants grown in commercial greenhouses were studied using g.l.c. Analysis of leaves at intervals following application showed that the initial residue of diazinon was higher than that of the other two insecticides, while its dissipation rate was faster. The dissipation of chlorpyrifos in fruits was faster than diazinon. The maximum residue levels (m.r.l.) of diazinon (0.5 mg kg?;1) and chlorpyrifos (0.1 mg kg?;1) were reached after 13 and 8 days of application respectively. With diazinon and pirimiphos-methyl, sprayed 3 weeks before inflorescence, very low concentrations of both insecticides were found in fruits, although these compounds have no systemic behaviour. Chlorpyrifos residue level of 0-2 mg kg ?;1 in harvested fruits did not drop below m.r.l. after 11 days holding period. 相似文献
7.
Nasir Abbas Muhammad Ismail Masood Ejaz Iqra Asghar Aima Irum Sarfraz Ali Shad Muhammad Binyameen 《Phytoparasitica》2018,46(3):411-419
Resistance management, targeting insect pests is one of the key components in developing integrated pest management strategies. Arguably, resistance monitoring is a scientific undertaking that can support and inform resistance management tactics and strategies. To monitor the current resistance status in Amrasca devastans against conventional insecticides (deltamethrin, bifenthrin, cypermethrin, chlorpyrifos, profenofos, acephate, and methomyl) which are used by the farming community as the predominant means to control this pest. Field populations of A. devastans were collected from six different districts: Multan, Bahawalpur, Khanewal, Lahore, Dera Ghazi Khan and Muzaffargarh from Punjab in Pakistan. The adult populations tested were 11.10–92.87 times more resistant to deltamethrin, 5.87–14.11 times more to bifenthrin, 3.16–17.5 times more to cypermethrin, 2.65–36.42 times more to chlorpyrifos, 7.28–57.71 times more to profenofos, 1.65–11.13 times more to acephate and 2.55–43.31 times more to methomyl as compared to control (lab population). In our study, no to high levels of resistance were observed against pyrethroids and organophosphates. Development of resistance to these pyrethroids and organophosphates might be due to the injudicious use of these types of insecticides in field crops. This study suggests that use of these insecticides should be minimized to avoid development of resistance in A. devastans. Future studies are also recommended to use new chemistry insecticides with novel modes of action and/or insecticide mixtures that may reduce the reliance of the farming communities on these insecticides. 相似文献
8.
为明确二嗪磷、毒死蜱和辛硫磷3种有机磷农药在双孢蘑菇栽培过程中的残留动态规律,采用在工厂化双孢蘑菇栽培基质 (覆土和培养料) 中拌料施药的方式,开展了田间试验,运用QuEChERS净化前处理技术结合UPLC-MS/MS分析,检测了3种农药在双孢蘑菇子实体和栽培基质中的残留动态。结果表明:建立的双孢蘑菇子实体、覆土和培养料3种基质中3种有机磷农药的液相色谱-串联质谱检测方法,经验证,在二嗪磷分别以0.000 3、0.003、0.1 mg/kg为添加水平,毒死蜱和辛硫磷分别以0.000 6、0.006、0.1 mg/kg为添加水平下,3种有机磷农药在双孢蘑菇、覆土和培养料3种基质中的平均回收率为76%~108%,相对标准偏差为2.2%~13%。检出限分别为:二嗪磷0.000 1 mg/kg、毒死蜱和辛硫磷均为0.000 2 mg/kg,定量限分别为:二嗪磷0.000 3 mg/kg、毒死蜱0.0006 mg/kg和辛硫磷0.000 6 mg/kg。在2 和10 mg/kg两个施药水平下,二嗪磷、毒死蜱和辛硫磷在双孢蘑菇栽培基质中的消解规律均符合一级反应动力学方程,在培养料中的消解半衰期分别为5.2、10.6、13.6 d和5.6、11.4、12.3 d;在覆土中的消解半衰期分别为25.9、41.7、27.2 d和41.7、48.1、36.8 d,且在培养料中的消解快于在覆土中的。在施药剂量不超过10 mg/kg的条件下,在双孢蘑菇子实体中毒死蜱残留量最高,为0.014 mg/kg,超过了欧盟规定的最大残留限量(MRL)标准,其余均低于现行日本、欧盟和美国规定的MRL值。 相似文献
9.
对目前中国主要蜜源作物上登记的农药品种进行了梳理,并采用现有的风险评估标准方法,对其中毒死蜱、吡虫啉等共61种杀虫剂对蜜蜂的风险进行了初级评估。结果表明:在58种喷雾施用的杀虫剂中,35种对蜜蜂的风险商值均大于1,风险为不可接受;其余23种的风险商值小于1,风险为可接受;所评估的6种土壤或种子处理内吸性杀虫剂中,5种对蜜蜂的风险商值大于1,风险为不可接受,仅氯虫苯甲酰胺的风险商值小于1,风险为可接受。但由于文中是以药剂在所登记作物上的单次最高施药剂量为暴露量进行的初级评估,并未考虑农药在花粉、花蜜中的降解及降雨引起的淋洗损耗,以及施药时间与作物花期之间的关系等影响因素,因而使得评估结果具有较大的保守性。研究结果一方面可为这些农药的合理使用和管理提供参考,另一方面提示了目前中国关于农药对蜜蜂的初级风险评估程序需进一步优化。 相似文献
10.
Geoffrey K Frampton 《Pest management science》1999,55(9):875-886
Contiguous winter wheat fields of similar cropping history and soil type were used in a study of the responses of Collembola to summer sprays of cypermethrin and pirimicarb in southern England. Chlorpyrifos was included in the study as a toxic standard. Epigeic arthropods were captured by suction sampling and crop-inhabiting species obtained by dissecting wheat ears. Eight genera of Collembola responded significantly to the insecticide treatments. Collembolan abundance decreased after chlorpyrifos was applied but increased after use of cypermethrin. Negative effects of cypermethrin and pirimicarb on Collembola were not detected in this study. Effects of chlorpyrifos varied spatially as a result of faunal heterogeneity among the fields, despite apparent homogeneity of the site. Some species known to be susceptible to chlorpyrifos were absent from one or more of the fields. The implications of these findings for the interpretation of non-target pesticide effects and the potential use of Collembola as bioindicators in field studies with pesticides are discussed. © 1999 Society of Chemical Industry 相似文献
11.
基于尾菜中存在农药残留的现状,以设施农业尾菜黄瓜秧为研究对象,采用气相色谱法和超高效液相色谱-串联质谱法检测了尾菜黄瓜秧在静态好氧发酵过程中多菌灵、吡虫啉、哒螨灵等50种农药残留的动态变化,并分析发酵重要影响因子堆高对农药残留消解的影响。结果表明:在尾菜黄瓜秧中共检测出腐霉利、多菌灵、嘧菌酯、苯醚甲环唑、烯酰吗啉、虫螨腈、吡虫啉、啶虫脒和哒螨灵9种农药残留,其中多菌灵平均残留量最高,达11.2 mg/kg,其他8种农药平均残留量在0.042~0.89 mg/kg之间。在发酵的24 d中,不同堆高条件下9种农药的消解规律均符合一级反应动力学方程,但不同农药半衰期差异较大,其中吡虫啉的平均半衰期最长,为28.9 d,多菌灵的平均半衰期最短,为10.2 d;不同堆高处理中农药的消解速率也有差异,总体上在2.5 m堆高下各农药的消解率最高、半衰期最短。本研究结果可为尾菜发酵参数优化、农业废弃物的高效资源化利用以及研发基于尾菜发酵产物的有机蔬菜专用有机肥提供理论支撑。 相似文献
12.
We investigated the sub-lethal influences of spinosad, chlorpyriphos, endosulfan, acephate and cypermethrin on the oviposition responses of Helicoverpa armigera (Hübner) to cotton plants, under cage and laboratory conditions. The rank order of toxicity (LC50 values as a per cent) of test insecticides against third instar larvae using the leaf disc method was: spinosad > chlorpyriphos > endosulfan > acephate > cypermethrin. On whole plants, females laid more eggs on acephate LC50-, acephate LC30- and cypermethrin LC50-treated cotton plants than on the control. The chlorpyriphos-treated plants were least preferred for oviposition. When excised cotton leaves from different treatments were used in a multiple-choice test, cypermethrin LC50- and endosulfan LC30-treated leaves received more eggs than the control. The repeated application of sub-lethal concentrations of different insecticides reduced plant height in the case of acephate LC30 and cypermethrin LC50, while plant spread and upper canopy leaf area were reduced in both treatments of acephate and cypermethrin. Reduced plant spread, upper canopy leaf area followed by plant height were found associated with oviposition preference by H. armigera females. 相似文献
13.
Organophosphorus, pyrethroid and chloronicotinyl insecticides have been used to control termites in building structures in recent years. We investigated the degradation behaviour of three insecticides (bifenthrin, chlorpyrifos and imidacloprid) at termiticidal application rates under standard laboratory conditions (25 °C, 60% field moisture capacity and darkness) for 24 months. The study was carried out on one soil and two bedding materials (sand-dolomite and quarry sand), which are commonly used under housing in Australia. Experiments were also conducted to examine the effect of soil moisture on the degradation of these insecticides. Insecticide residues in the samples collected at different days after application were measured by high performance liquid chromatography (HPLC). The rate of degradation of bifenthrin and imidacloprid insecticides was adequately described by a first-order kinetic model (r2 = 0.93–0.97). However, chlorpyrifos degradation was biphasic, showing an initial faster degradation followed by a slower rate. Therefore, the degradation data during the slower phase only (after a two-month period) followed the first-order law (r2 = 0.95). Soil moisture had little effect on degradation of imidacloprid and bifenthrin. Among the three insecticides, bifenthrin and imidacloprid were most stable and chlorpyrifos the least. Chlorpyrifos showed a major loss (75–90%) of residue during the 24 months incubation period. In the bedding materials, simultaneous accumulation of the primary metabolite of chlorpyrifos, TCP (3,5,6-trichloro-2-pyridinol) was observed. Hydrolysis appeared to have caused the observed rapid loss of chlorpyrifos, especially in the highly alkaline bedding materials (sand-dolomite and quarry sand). © 1999 Society of Chemical Industry 相似文献
14.
毒死蜱、吡虫啉、螺虫乙酯及其代谢物和苯醚甲环唑在梨中的残留消解动态 总被引：2，自引：0，他引：2
利用仪器分析方法和田间试验法,研究了毒死蜱、吡虫啉、螺虫乙酯及其代谢物和苯醚甲环唑在梨中的残留消解动态。样品经乙腈提取,氯化钠盐析净化,毒死蜱采用气相色谱-质谱联用仪检测,其他3种农药采用液相色谱-质谱联用仪检测,外标法定量。结果表明:毒死蜱、吡虫啉、螺虫乙酯及其代谢物和苯醚甲环唑4种农药在梨中的消解动态均满足一级反应动力学方程,半衰期分别为4.4、12.2、13.1和10.3 d。施药后7 d至收获期,4种农药在梨中的最终残留量均未超出中国国家标准中规定的最大残留限量值,按照推荐剂量及其操作规范在梨上施用是安全的。 相似文献
15.
为了考察敌百虫、毒死蜱、氯氰菊酯和多菌灵4种农药在莼菜加工过程中的加工因子,从而优化莼菜的加工过程,分别模拟莼菜加工的清洗、杀青、护绿和储藏4个步骤,考察4种农药的加工因子,并分析每个步骤的相关因素对加工因子的影响。采用气相色谱-火焰光度检测器（GC-FPD）检测敌百虫和毒死蜱的含量,气相色谱-电子捕获检测器（GC-ECD）检测氯氰菊酯的含量,液相色谱-二极管阵列检测器（LC-DAD）检测多菌灵的含量。结果表明:随着清洗时间的增加,4种农药的加工因子逐渐变小,并在一定时间后趋于稳定;在供试的10 min内,杀青时间越长,4种农药的加工因子越小;护绿和储藏条件的改变对加工因子均无显著影响。综合考虑莼菜品质和农药残留两方面因素,建议莼菜清洗时间为30 min,在不影响莼菜品质的前提下尽量延长杀青时间。 相似文献
16.
Pyrethroid insecticides were applied on various vegetable crops as foliar treatments to determine dissipation rates. On Chinese broccoli (Guy Lon), Chinese mustard (Pak Choi) and Chinese cabbage (Kasumi, napa), fenvalerate was persistent with residues of 0.10, 0.14 and 0.11 mg kg-1, respectively, by day 21. Cypermethrin residues on head lettuce were below 0.1 mg kg-1 by day 10 but on the leafier romaine and endive varieties it was more persistent and required 14-19 days to dissipate below this concentration. After three applications, residues of cypermethrin in harvested carrots and of permethrin in eggplant were not detected on the day of application. On asparagus, deltamethrin and cypermethrin residues declined to less than 0.1 mg kg-1 by days 1 and 2, respectively; permethrin was more persistent, requiring more than 2 days to decline to less than 0.1 mg kg-1. Deltamethrin on dry (cooking) and Spanish onions was not detected on the day of application. On tomatoes, the concentration of permethrin was 0.093 mg kg-1 on the day of application and declined to about 0.05 mg kg-1 after 2-4 days. In general, permethrin, cypermethrin and deltamethrin residues declined to acceptable concentrations within an acceptable pre-harvest interval. Fenvalerate may be too persistent on these speciality crops unless a maximum residue limit > 0.1 mg kg-1 is permitted. 相似文献
17.
Heinz E. Braun Gwen M. Ritcey Richard Frank Freeman L. McEwen Brian D. Ripley 《Pest management science》1980,11(6):605-616
Dissipation rates of diazinon, endosulfan, leptophos, methamidophos, methomyl, parathion and pirimicarb were studied on five minor vegetable crops, including cos and head lettuce, endive, cauliflower and Chinese cabbage. Residues from foliar treatment generally followed an exponential rate of decline. The number of days for residues to drop to below acceptable tolerances was highly dependent on the magnitude of the initial residue; large variations in initial residues were observed between years, between insecticides, and between crop types. Residues of five insecticides and two fungicides used in furrow treatments for onions intended for pickling were determined in the onions at harvest and after pickling. Fensulfothion and fonofos levels were below the accepted tolerance of 0.1 mg kg?1 at harvest, while chlorfenvinphos, chlorpyrifos and ethion were present above this level; fungicide residues were not detected. Following pickling, only ethion residues were still present in the onions at levels greater than 0.1 mg kg?1. 相似文献
18.
模拟加工对菠菜中农药残留量及膳食暴露评估的影响 总被引：1，自引：1，他引：0
采用田间喷药、室内模拟加工和气相色谱检测方法,研究了水洗、漂烫和烘干处理对菠菜中毒死蜱、氯氰菊酯和氰戊菊酯残留量的影响。结果表明:在田间推荐剂量下,当毒死蜱、氯氰菊酯和氰戊菊酯的有效成分用量分别为0.038 8、0.001和0.01 g/m2时,经水洗和漂烫处理,菠菜中上述3种农药的残留量分别降低22.6%、53.8%和50.8%;而加倍剂量处理时,则分别降低8.5%、61.4%和40.2%;烘干处理对毒死蜱的去除作用大于50%,但对氯氰菊酯和氰戊菊酯的去除作用仅为10%左右。对新鲜菠菜和干制菠菜的农药残留量进行膳食暴露评估的结果表明,合理的加工方式可以降低农药膳食摄入估计量的62.1%~76.7%。研究结果表明:毒死蜱的残留受水洗和漂烫影响较小,受烘干影响较大;而氯氰菊酯和氰戊菊酯的残留受水洗与漂烫影响较大,受烘干影响较小;引入加工因子后膳食暴露评估结果更接近真实值。 相似文献
19.
Field bioassays were conducted to assess the toxicity of three insecticides, chlorpyrifos, cypermethrin and pirimicarb, to four species of springtails, Isotoma viridis, Isotomurus palustris, Folsomia candida (Collembola: Isotomidae) and Sminthurus viridis (Collembola: Sminthuridae). Spray residues on two soil types (a sandy clay loam and a sandy soil) were obtained in the field, in the presence and absence of a wheat crop canopy, after spray application by a commercial tractor-mounted sprayer. Collembola were then confined for 24-h periods on the sprayed soils in a constant laboratory environment at 1, 2, 3, 8 and 15 days after treatment. Residual insecticide toxicity was compared between species, insecticides, soils and exposure conditions (crop or no crop) using the age of residue at which median mortality occurred (DAT50). Cypermethrin and pirimicarb residues were of low toxicity, causing less than 10% mortality, whereas residues of chloryprifos were toxic to all four species of Collembola on both soil types and in both exposure treatments. Interspecific differences in collembolan susceptibility to chlorpyrifos residues gave the ranking (from most to least susceptible) S. viridis>F. candida>Isotomurus palustris>Isotoma viridis. Residues on the sandy soil were more toxic than those on the sandy clay loam. These results are discussed in terms of how field bioassay approaches may be used to determine pesticide residual toxicity to microarthropods. We conclude that field bioassays offer a feasible method for evaluating the toxicity of pesticides and the persistence of toxic effects on Collembola. Advantages and disadvantages of this method are considered. 相似文献
20.
P BENOIT J PERCEVAL† M STENRØD† C MONI† O M EKLO† E BARRIUSO T SVEISTRUP‡ & J KVÆRNER‡ 《Weed Research》2007,47(6):517-526
Herbicide degradation in soils is highly temperature‐dependent. Laboratory incubations and field experiments are usually conducted with soils from the temperate climatic zone. Few data are available for cold conditions and the validation of approaches to correct the degradation rate at low temperatures representative of Nordic environments is scarce. Laboratory incubation studies were conducted at 5, 15 and 28°C to compare the influence of temperature on the dissipation of metribuzin in silt/sandy loam soils in southern and northern Norway and in a sandy loam soil under temperate climate in France. Using 14C‐labelled metribuzin, sorption and biodegradation were studied over an incubation period of 49 days. Metribuzin mineralisation and total soil organic carbon mineralisation rates showed a positive temperature response in all soils. Metribuzin mineralisation was low, but metabolites were formed and their abundance depended on temperature conditions. The rate of dissipation of 14C‐metribuzin from soil pore water was strongly dependent on temperature. In Nordic soils with low organic content, metribuzin sorption is rather weak and biodegradation is the most important process controlling its mobility and persistence. 相似文献