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1.
为明确手性农药氯氟醚菌唑 (mefentrifluconazole,MFZ)在水稻环境中的立体选择性行为,本研究基于高效液相色谱-串联质谱 (HPLC-MS/MS)法建立了氯氟醚菌唑对映体在水稻植株、根系、土壤和田水中的残留测定方法,并通过水稻环境盆栽模拟试验,考察了氯氟醚菌唑在水稻环境中的行为规律及微塑料对氯氟醚菌唑在水稻环境中的立体选择性及降解动态的影响。结果表明:氯氟醚菌唑对映体在手性柱Chiralpak IG上可完全分离,且在0.0005~0.1 mg/L范围内,对映体的峰面积与相应的质量浓度间呈良好线性关系 (R2均大于0.999),其在水稻环境样本中的平均回收率为76%~108%,相对标准偏差 (RSD)为1.3%~12%。盆栽模拟试验结果表明,氯氟醚菌唑对映体在水稻植株、根系、土壤和田水中均无立体选择性差异 (P>0.05);微塑料对氯氟醚菌唑在水稻环境中的立体选择性无显著影响 (P>0.05),但可显著延长其在田水和水稻植株中半衰期。氯氟醚菌唑R体和S体在田水中的半衰期分别从6.7和6.7 d延长至11.6和11.7 d,在水稻植株中则分别从7.5和7.4 d延长至11.7和11.6 d。该结果可为氯氟醚菌唑在水稻环境中的合理使用提供参考。 相似文献
2.
腈菌唑在番茄果实中的立体选择性降解 总被引：1，自引：0，他引：1
为明确田间条件下手性杀菌剂腈菌唑对映体在番茄果实中的降解规律，采用Lux Cellulose-1手性色谱柱及超高效液相色谱-串联三重四极杆质谱 (UPLC-MS/MS) 分析方法，研究了腈菌唑对映体的分离及其在番茄果实中的选择性降解。样品经乙腈提取，采用QuEChERS 方法净化。分析方法验证结果表明:在0.000 5~0.05 mg/L线性范围内，腈菌唑对映体的峰面积与其浓度间呈良好的线性关系，R2均大于0.99；在0.005、0.05和0.25 mg/kg 3个添加水平下，腈菌唑对映体在番茄中的平均回收率在92%~96%之间，相对标准偏差 (RSD) 在1.0%~3.0%之间。降解试验结果显示:腈菌唑对映体在番茄果实中的降解规律符合一级反应动力学方程，其降解半衰期在2.77~4.08 d之间；腈菌唑对映体在番茄果实中的降解具有明显选择性，随时间延长，其对映体分数 (FE) 值由最初的0.47下降为0.24，其中S-(+)-腈菌唑优先降解，从而导致R-(–)-腈菌唑的相对富集。本研究从对映体的角度评价了腈菌唑在番茄中的降解，可为手性农药对映体的环境行为研究提供基础数据。 相似文献
3.
采用超临界流体色谱,以超临界二氧化碳(CO2)作为流动相,研究了6种手性三唑类杀菌剂(苄氯三唑醇、联苯三唑醇、叶菌唑、乙环唑、糠菌唑和醚唑)在Chiralcel OD-H手性色谱柱上的对映体分离。考察了不同改性剂种类(甲醇、乙醇、异丙醇)、体积分数(0~15%)以及系统背压(13~17 MPa)对分离效果的影响,并与其在Sino-Chiral OJ和Chiralpak IB手性色谱柱上的分离效果进行了比较。结果表明:单独以超临界CO2为流动相时,6种三唑类杀菌剂的保留时间均大于60 min,而添加了醇类改性剂后其在40 min内均得到了洗脱。苄氯三唑醇、联苯三唑醇、叶菌唑和糠菌唑在柱温为34℃、系统背压为15 MPa、流动相流速为2 m L/min时,在20 min内均实现了基线分离(Rs≥1.5);优化改性剂(体积分数)分别为3%乙醇、13%乙醇、6%甲醇和7%乙醇。Chiralcel OD-H柱对6种供试杀菌剂的手性识别效果优于Sino-Chiral OJ和Chiralpak IB柱,但对映体分离时间要长10~20 min。 相似文献
4.
建立并优化了基于超高效液相色谱-串联质谱 (UPLC-MS/MS) 同时检测水稻中甲氨基阿维菌素苯甲酸盐、氯虫苯甲酰胺、氟唑菌酰胺及其代谢物M700F008、M700F048的分析方法。稻壳和糙米经0.2%甲酸-乙腈提取后用C18净化，稻秆经1%甲酸-乙腈提取后用N-丙基乙二胺 (PSA) 和石墨化碳黑 (GCB) 净化，流动相为甲醇和0.2%甲酸水溶液，梯度洗脱，采用T3色谱柱进行分离。电喷雾正离子模式 (ESI+) 采集，多反应监测 (MRM)，外标法定量。结果表明:5种供试化合物的质量浓度与峰面积间线性关系良好，决定系数均大于0.9955；5种化合物在水稻稻壳、糙米及稻秆3种基质中的平均回收率均在71%~119%之间，相对标准偏差 (RSD) 在1%~11%之间，满足残留分析的要求。在3地供试糙米样品中，甲氨基阿维菌素苯甲酸盐、氯虫苯甲酰胺和氟唑菌酰胺的残留量均低于中国规定的最大残留限量标准。 相似文献
5.
本研究建立了液相色谱-串联质谱法(HPLC-MS/MS)同时检测土壤和水中啶菌噁唑及其8种降解产物的多残留分析方法?土壤样品经乙腈提取后, 弗罗里硅土净化; 水样品分别采用直接用0.22 μm水系滤膜过滤及乙腈提取的方式?净化后的样品采用Poroshell 120 EC-C18色谱柱, 以乙腈和0.2%甲酸水作为流动相进行梯度洗脱, 再使用高效液相色谱串联质谱检测分析?结果表明:啶菌噁唑及其降解产物在土壤和水中的定量限分别为1.0 μg/kg和0.1 μg/L, 其在土壤和水中的标准工作曲线分别在0.05~10 μg/L和0.1~50 μg/L范围内表现出良好的线性关系, 决定系数(R2)均大于0.99?啶菌噁唑及其降解产物在土壤中的平均回收率为71%~111%, 相对标准偏差为0.9%~10.9%; 在水中的平均回收率为80%~111%, 相对标准偏差为0.1%~7.5%?应用该方法对北京4地的地表水进行检测, 均未检出啶菌噁唑及其降解产物?该方法简便?准确?灵敏度高, 适用于啶菌噁唑及其降解产物在土壤和水中的残留检测? 相似文献
6.
含两个手性中心的三唑类杀菌剂色谱分离研究进展 总被引：1，自引：0，他引：1
三唑类杀菌剂是目前世界上广泛应用的杀菌剂,而绝大多数三唑类杀菌剂属于手性农药,具有1个或2个手性中心,存在2个或4个对映异构体。本文在近年有关三唑类杀菌剂研究成果的基础上,综述了采用高效液相色谱、超临界流体色谱、毛细管电泳、气相色谱和合相色谱法等方法对含两个手性中心的11种三唑类杀菌剂 (氟环唑、多效唑、三唑醇、联苯三唑醇、丙环唑、苯醚甲环唑、叶菌唑、苄氯三唑醇、环唑醇、糠菌唑和乙环唑) 进行分离测定的研究进展,可为多个手性中心三唑类化合物的分离、分析和深入研究提供参考。 相似文献
7.
冬小麦品种‘兰天23号’苗期抗条锈性遗传分析 总被引：1，自引：0，他引：1
2014年在甘肃省农业科学院植物保护研究所兰州温室,进行了‘兰天23号’/‘铭贤169’组合的亲本及其F1、F2、BC1代对条锈菌主要流行小种CYR32、CYR33及新菌系G22-9的遗传分析。结果表明,接种CYR33,F2代植株抗感分离比为144R∶54S,符合3R∶1S的理论比值;接种CYR32,F2代植株抗感分离比为62R∶22S,符合3R∶1S的理论比值;接种G22-9,F2代植株抗感分离比为85R∶24S,符合3R∶1S的理论比值;F1代植株对供试菌系均表现免疫,BC1代植株抗感分离比均符合1R∶1S的理论比值,表明‘兰天23号’对3个供试条锈菌系的抗病性均由1对显性抗性基因控制。通过系谱分析推知,该抗病基因来源于抗病亲本‘SXAF4-7’。 相似文献
8.
基于手性固定相/高效液相色谱- 串联质谱结合QuEChERS前处理技术建立了柑橘中丙溴磷对映体残留的分析方法，并通过田间试验研究了丙溴磷对映异构体在柑橘中的选择性降解行为。柑橘样品经乙腈快速提取，多壁碳纳米管净化。丙溴磷对映体采用ND(2)-RH手性色谱柱分离，正离子多反应监测模式 (MRM) 检测，基质匹配标准曲线法定量。方法验证结果表明，丙溴磷对映体在2.5~250 μg/L质量浓度范围内线性关系良好 (r ≥ 0.999 6)，方法定量限 (LOQ) 为5 μg/kg。在3个添加水平(5、100、500 μg/kg)下，丙溴磷对映体的平均回收率为76%~83%，相对标准偏差 (RSD) 为2.6%~6.0%。田间试验结果表明，丙溴磷对映体在柑橘中的降解规律符合一级反应动力学方程，(+)-丙溴磷和 (?)-丙溴磷的降解半衰期分别为12.53 d和14.14 d；在施药后30 d，丙溴磷2个对映体的对映体分数值达到0.43，表明其在柑橘中的降解存在明显的对映体选择性差异。 相似文献
9.
QuEChERS-高效液相色谱-串联质谱法测定榛子中4种农药的残留 总被引：1，自引：0，他引：1
建立了同时检测榛子中苯醚甲环唑、丙环唑、噻虫嗪和啶虫脒4种农药残留量的QuEChERS-高效液相色谱-串联质谱 (HPLC-MS/MS) 检测方法。榛仁和榛壳分别经正己烷饱和的乙腈和乙腈提取,用弗罗里硅土、石墨化碳黑 (GCB) 和N-丙基乙二胺 (PSA) 净化。C18色谱柱分离,采用电喷雾正离子 (ESI+) 扫描,在多重反应监测 (MRM) 模式下进行质谱分析,外标法定量。结果表明:在0.01～2 mg/kg范围内,苯醚甲环唑、丙环唑、噻虫嗪和啶虫脒4种供试农药的质量浓度与对应的峰面积间呈良好线性关系 (R2 > 0.990 2)。在0.01、0.1和1 mg/kg 3个添加水平下,4 种农药在榛子中的日内平均回收率为79%～111%,相对标准偏差 (RSDs) (n = 5) 为0.6%～6.9%,日间平均回收率为81%～110%,RSDs (n = 15) 为1.1%～8.5%。4种农药的定量限均为0.01 mg/kg。此方法简单、高效,可为榛子等坚果类食品中多种农药残留的同时测定提供参考。 相似文献
10.
三七圆斑病菌槭菌刺孢对嘧菌酯、咪鲜胺和苯醚甲环唑的敏感性及生存适合度分析 总被引：1，自引：0，他引：1
采用菌丝生长速率法测定了采自云南省5个三七主要产区的34株三七圆斑病原菌槭菌刺孢Mycocentrospora acerina (R. Hartig) Deighton对嘧菌酯、咪鲜胺和苯醚甲环唑的敏感性，并对不同敏感性菌株进行了生存适合度测定。结果表明:咪鲜胺、嘧菌酯及苯醚甲环唑对所有供试槭菌刺孢的菌丝生长均有明显的抑制作用，3种杀菌剂的EC50值分别在0.03~1.91 mg/L、0.18~2.36 mg/L和0.45~2.15 mg/L之间，即该菌株对咪鲜胺的敏感性对高于嘧菌酯和苯醚甲环唑；低敏感性菌株的致病力和菌丝生长速率与敏感性菌株间无显著差异，说明供试槭菌刺孢菌株在当地均具有较高的生存适合度。 相似文献
11.
Fungicides containing the imidazole and triazole groups are known to block the 14α-demethylation reaction in ergosterol biosynthesis, which is a cytochrome P-450 enzyme system. Fungicides related to diclobutrazol [(2RS, 3RS)-1-(2,4-dichlorophenyl)-4,4-dimethyl-2-(1,2,4-triazol-1-yl)pentan-3-ol] bind to cytochrome P-450 in rat liver microsomes, whole yeast cells, yeast microsomes and to a partially purified cytochrome P-450 from yeast, with Type II spectral changes. The most fungicidally active isomer (2R, 3R) shows greater binding than the less active (2S, 3S)-enantiomer to yeast microsomes; when the cytochrome P-450 was purified, a preparation was obtained to which binding more closely matched the fungicidal activity. Binding to rat liver microsomes does not reflect the fungicidal activity of the compounds. 相似文献
12.
The systemic fungicide triadimenol is a mixture of four enantiomers which have different biological activities. Dissipation and metabolism of the individual enantiomers in soil were investigated after seed treatment. Forty-nine days after 1R2S and 1S2S treatments, more of the radioactivity (87% for both) had dissipated from the seeds into the 0–10 cm soil layer than after the 1S2R (76%) and 1R2R (73%) treatments. After 1R2S treatment 56% of the radioactivity extracted from soil was accounted for as the parent isomer and 44% as its 1R2R epimer. After 1S2R treatment 76% of the radioactivity was in the parent form and 24% was converted to the 1S2S (17%) and 1R2R (7%) isomers. 相似文献
13.
Laboratory tests in a fly chamber and field trials in the UK and Australia have shown that permethrin, (3-phenoxybenzyl (1R,1S)-cis,trans-3-(2,2-dichlorovinyl)-2, 2-dime-thylcyclopropanecarboxylate) containing 25: 75 cis: trans isomers, applied as water emulsions to cattle and horses will control biting flies. Satisfactory protection against the stable fly, Stomoxys calcitrans (L.) and excellent control against the horn fly, Haematobia (Lyperosia) irritans (L.) was achieved on cattle. Good control was obtained on horses against the stable fly and the sand fly Culicoides spp. These early results are encouraging and toxicity and residue data suggest that permethrin would be a safe insecticide to use on livestock for the control of biting flies of veterinary importance. 相似文献
14.
用高效液相色谱法紫外检测器分别测定氯氰菊酯中的高顺式异构体（１Ｒ，３Ｒ，１Ｓ，３Ｓ）－顺式（ＳＲ）高反式异构体（１Ｒ，３Ｓ，１Ｓ，３Ｒ）－反式（ＳＲ）；高顺，高反式混合体以及高顺，高反，低顺，低反混合体（简称四对混合体）响应值，实验分别采用两种内标物做内标法测定，结果表明四对异构体对紫外检测器器的响应值是一致的。 相似文献
15.
M. Humayoun Akhtar Robert M. G. Hamilton H. Locksley Trenholm 《Pest management science》1987,20(1):53-73
Radiolabelled racemic cypermethrin, and the cis and trans isomers of 3-(2,2-dichlorovinyl)-2,2-dimethylcyclopropanecarboxylic acid (labelled at C-1 of the cyclopropane ring) were each separately administered orally in feed for three consecutive days to White Leghorn laying hens. The amount of individual compound dosed was approximately 7.5 mg per hen per day. Radiocarbon was eliminated very rapidly in excreta. Tissue residues were generally very low with the exception of fat depots, but trace amounts of radiocarbon residues were still detectable in fat, liver and kidney 11 days post-treatment. Residues were detected in the egg albumen of hens treated with cypermethrin and cis isomer of the acid, but none was detected from trans acid. Metabolites identified included products arising from the hydrolysis of the ester bond of cypermethrin, followed by oxidative attack on one or both methyl groups. The rate of oxidative attack on methyl groups was influenced by the geometry of the dichlorovinyl group. On the basis of the metabolites identified a metabolic pathway for cypermethrin in laying hens was proposed which included hydrolysis of the ester bond followed by oxidation of methyl group(s). The data indicate that use of cypermethrin as recommended should not produce residues in eggs and meat of laying hens at levels that are of toxic concern. 相似文献
16.
Ujjana B. Nandihalli Mary V. Duke John W. Ashmore Vincent A. Musco Robert D. Clark Stephen O. Duke 《Pest management science》1994,40(4):265-277
Protoporphyrinogen oxidase (Protox) was inhibited stereoselectively by three pairs of enantiomers belonging to diphenyl ether (DPE) and pyrazole phenyl ether (PPE) herbicide classes. The (R) enantiomers were 10- to 44-fold more active than the (S) enantiomers as inhibitors of Protox from barley etioplasts. Similarly, the (R) enantiomers caused green barley tissue to accumulate greater amounts of porphyrins and caused greater tissue damage than the (S) enantiomers. The (R) enantiomers competed more successfully with [ 14 C]acifluorfen than the (S) enantiomers for the binding sites on Protox. In the PPE class, the in-vitro and in-vivo activity differences were wider in the isopropyl pairs than in the n-propyl pairs. The DPE enantiomers were tested on ten dicotyledonous and six monocotyledonous weed species and ten crops for weed control and crop safety. In general, neither enantiomer had pre-emergence activity on monocotyledons, but the (R) enantiomer provided some monocotyledonous weed control when applied post-emergence. On dicotyledons, the (R) enantiomer provided excellent pre-emergence control, whereas the (S) enantiomer was inactive. The (R) enantiomer caused no injury to corn, cotton, peanuts, rice, sorghum, or soybeans applied pre-emergence, but it severely injured crops when applied post-emergence. There was a positive correlation between the activities of the compounds at the molecular, cellular and whole plant levels. The only molecular property differences found to account for differences in activity between members of chiral pairs were steric parameters. 相似文献
17.
Wolfgang Krmer Dieter Berg Stefan Dutzmann Wilfried A Etzel Wolfgang Gau Ulrich Stelzer Joachim Weissmüller 《Pest management science》1999,55(5):610-614
KWG 4168 (8-tert-butyl-1,4-dioxaspiro[4,5]decan-2-ylmethyl(ethyl)(propyl)amine; proposed common name spiroxamine) is a new fungicide consisting of four biologically active isomers (two diastereomers, four enantiomers). The four isomers were separated by preparative HPLC on a chiral stationary phase. The diastereoisomers were synthesised from the corresponding chirally pure glycerol derivatives and were separated by preparative HPLC. COSY, HSQC and NOESY NMR spectroscopy were used to asign the configuration of the amino residue relative to the cyclohexyl ring. Studies of the activity against wheat powdery mildew, as well as the inhibition of sterol biosynthesis in fungi by the four stereoisomers, indicate the contribution of each isomer to the biological activity of spiroxamine. 相似文献
18.
高效氯氟氰菊酯不同抗性基因型甜菜夜蛾相对适合度研究 总被引：4，自引：0，他引：4
在室内相同条件下 ,构建了甜菜夜蛾高效氯氟氰菊酯抗性种群 (R)、敏感种群(S)、正交 F1代 (RS)、反交 F1代 (SR)和对照种群 (CK)的生命表 ,研究了各种群的产卵量、卵孵化率、幼虫和成虫发育历期和蛹重等主要生物学特性。抗高效氯氟氰菊酯基因型甜菜夜蛾在生活力和繁殖力上与其它基因型比较均存在一定程度的不利性 ,杂合子的大部分生物学特性与敏感基因型比较差异不显著。在经过一个完整世代后 ,R、S、RS、SR和 CK种群的净增殖率(R0 )分别为 117.8、624.7、589.1、642 .3、218.8。以敏感种群为参比 ,S、RS、SR、R和 CK种群的相对适合度分别为 1、0 .934、1.028、0.188和 0 .368。与敏感品系 S相比 ,SR和 RS品系的相对适合度无变化 ,抗高效氯氟氰菊酯种群适合度明显降低。 相似文献
19.
Philip J. McCall 《Pest management science》1987,19(3):235-242
Hydrolysis of [14C]-radiolabeled 1, 3-dichloropropene (1, 3-D) was studied at pH 5, 7 and 9 at 10, 20 and 30°C in sterile buffered water. The rate of hydrolysis was independent of pH at each temperature, with measured half-lives of 3-1 (±0.l), 11.3 (±0.5) and 51 (±2.3) days at 30, 20 and 10°C, respectively. The activation energy for the hydrolysis reaction was determined to be 23.9 kcal mol?1 deg?1. One hydrolysis product was formed during the course of the study and was identified by co-chrornatography with analytical standards, using h.p.l.c., to be 3-chloroallyl alcohol. The alcohol appeared to be stable to further hydrolytic conversion and was formed in the same cis: trans ratio as in the initial 1, 3-D starting material, indicating essentially identical rates of hydrolysis for the cis and trans isomers of 1, 3-D. 相似文献
20.
Diclobutrazol [(2RS, 3RS)-1-(2, 4-dichlorophenyl)-4, 4-dimethyl-2-(1,2, 4-triazol-1-yl)pentan-3-ol] decreased the rate of growth of Ustilago maydis during the log phase. Marked changes in sterol composition were observed with a decrease in ergosterol and an increase in methyl-sterols, indicating a block in the removal of the 14-methyl group. The inhibition was of rapid onset (<4 h). Changes in other lipid constituents were minor and there was no build up of unsaturated fatty acids. The fungicidal activity resides in the (2R, 3R)-isomer, which is known to be more potent in blocking a yeast 14-demethylase enzyme than the (2S, 3S)-isomer. This relationship held in the 4-chlorophenyl homologues, which as a group were less fungicidal and less potent inhibitors than the 2, 4-dichlorophenyl compounds. The evidence presented indicates that the primary lesion caused by the fungicide was a build up of membrane sterols containing extra methyl groups; this, in combination with a loss of ergosterol, is believed to prevent proper membrane ordering and thus to cause a loss of membrane function. 相似文献