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1.
建立了一种同步检测稻田中硝磺草酮和2甲4氯残留的固相萃取-高效液相色谱-串联质谱(SPE-LC-MS/MS)分析方法。样品经乙酸乙酯提取后,用PSA吸附、C18固相萃取小柱净化,C18色谱柱分离,0.1%甲酸水-0.1%甲酸甲醇溶液为流动相,梯度洗脱分离,在电喷雾ESI离子源正、负离子模式下,采用质谱多反应监测(MRM)模式定性分析。结果表明:硝磺草酮和2甲4氯的检出限(LOD)分别为0.005和0.025 ng,定量限(LOQ)分别为0.01和0.05 mg/L。在0.001~2 mg/L和0.005~5 mg/L范围内,硝磺草酮和2甲4氯的质量浓度与对应的峰面积间呈良好的线性关系,其相关系数均大于0.999 7。在0.01~2 mg/L添加水平下,硝磺草酮在田水、土壤、植株、稻壳和糙米中的平均回收率为75%~103%,相对标准偏差(RSD)为0.1%~8.2%;在0.05~10 mg/L添加水平下,2甲4氯在田水、土壤、植株、稻壳和糙米中的平均回收率为90%~113%,RSD为0.5%~7.4%。说明该方法高效、快捷、精确度高,能够满足硝磺草酮和2甲4氯钠在稻田中的残留量检测分析要求。  相似文献   

2.
2甲4氯人工抗原的合成与鉴定   总被引:8,自引:5,他引:8       下载免费PDF全文
以除草剂2甲4氯(MCPA,简写为M)、氯化亚砜、氨基己酸和氨基丁酸等为起始原料,经两步化学反应分别合成了两种MCPA半抗原:6-(2-甲基-4-氯苯氧乙酰基)氨基己酸(MC)和4-(2-甲基-4-氯苯氧乙酰基)氨基丁酸(MB)。并通过碳二亚胺法和混合酸酐法将MCPA、MC和MB分别与载体蛋白(BSA、OVA)偶联制备了2甲4氯的免疫抗原和包被抗原。再将M-BSA、MC-BSA和MB-BSA分别免疫新西兰大白兔获得了3种抗2甲4氯的多克隆抗体:抗M-BSA抗体(M-Ab)、抗MC-BSA抗体(MC-Ab)和抗MB-BSA抗体(MB-Ab),当相应的包被抗原浓度均为4 μg/mL时,相应的冻干粉效价分别为1.0×106,1.2×106和2.0×106。在同源反应中,仅M-Ab适用于2甲4氯的残留检测,其线性浓度范围为0.01~10 mg/L(IC50为1.3 mg/L,MC-Ab 和MB-Ab均大于50 mg/L),最低检测限为0.01 mg/L。研究结果为进一步研制2甲4氯快速检测试剂盒奠定了基础。  相似文献   

3.
为了明确稻鳝种养田杂草群落组成及除草剂安全用药技术,采用取样计数的方法调查了稻鳝种养田杂草种类及田间密度,并采用静水式试验法在室内条件下测定了稻田常用除草剂对黄鳝生长的影响。结果表明,稻鳝种养降低了杂草的丰富度、多样性和均匀度,杂草危害减轻。茎叶处理除草剂100 g/L氰氟草酯EC、25 g/L五氟磺草胺OD、13%2甲4氯钠AS和480 g/L灭草松AS对黄鳝生长安全,可安全应用于稻鳝种养田防除杂草。土壤处理除草剂中,30%丙草胺EC、10%吡嘧磺隆WP、40%苄嘧磺隆·丙草胺WP对黄鳝生长安全,是稻鳝种养田使用土壤处理除草剂的优先选择。60%丁草胺EC和12%噁草酮EC与黄鳝的死亡率存在着明显的剂量-效应关系,随着浓度的提高,黄鳝死亡率显著上升,不推荐用于稻鳝种养田防除杂草。  相似文献   

4.
建立了同时测定大米中西草净、异丙隆、苄嘧磺隆、莎稗磷、乙氧氟草醚、草酮和二甲戊灵7种除草剂残留的QuEChERS-高效液相色谱-串联四极杆飞行时间质谱 (HPLC-MS/MS Triple TOF) 方法。样品经V (乙酸乙酯) : V (水) = 80 : 20混合溶液提取,以N-丙基乙二胺 (PSA) 为吸附剂进行基质分散萃取净化,采用HPLC-MS/MS Triple TOF检测,外标法定量。结果表明:7种除草剂在一定的质量浓度范围内,其峰面积与对应的质量浓度间线性关系良好,相关系数均大于0.99;西草净、异丙隆、苄嘧磺隆和莎稗磷在0.001、0.01、0.05 mg/kg 3个添加水平下的平均回收率在75%~108%之间,相对标准偏差 (RSD) 在1.1%~7.0% (n = 5) 之间,定量限 (LOQ) 均为0.001 mg/kg;乙氧氟草醚、草酮和二甲戊灵在0.01、0.05和1 mg/kg 3个添加水平下的平均回收率在81%~108%之间,RSD在2.7%~9.0%之间,LOQ均为0.01 mg/kg。该方法样品前处理简单快速,方法灵敏度、准确度和精密度均符合农药残留检测要求,可用于大米中西草净、异丙隆、苄嘧磺隆、莎稗磷、乙氧氟草醚、草酮和二甲戊灵残留的同时检测。  相似文献   

5.
苄嘧磺隆是目前稻田常用的土壤封闭除草剂品种之一,研究建立其毛细管电泳分析方法,可以为苄嘧磺隆的残留检测和环境行为研究提供一种经济灵敏的方法选择。建立苄嘧磺隆毛细管电泳分析方法,以50 mmol/L醋酸钠(pH值4.8,含12%乙腈)为缓冲液,采用10.5 kV工作电压,240 nm检测波长。结果表明,苄嘧磺隆的保留时间为14.6 min,最低检测浓度为0.2 mg/L,在0.4~10.0 mg/L浓度范围内与峰面积有良好的线性关系(y=991.52x+403.67,r~2=0.990 1)。该方法可同时检测样品中的丙酮,因此可以将丙酮作为分析苄嘧磺隆的内标物。  相似文献   

6.
林业除草剂咪唑烟酸在土壤、水及杂草植株中的残留检测   总被引:6,自引:0,他引:6  
采用HPLC建立了一种林业常用除草剂咪唑烟酸在土壤、水及杂草植株中的残留检测方法。土壤及杂草植株样品用甲醇+0.1mol/L的NH4HCO3水溶液(体积比70∶30)提取,水溶液样品直接用二氯甲烷萃取。 添加法测定结果表明:当添加水平为0.1~5 mg/kg时,平均回收率为86.9%~103.5% 。在土壤及杂草植株中的最小检知浓度分别为0.05、0.1 mg/kg;水中最小检知浓度为0.01 mg/L。  相似文献   

7.
直播稻田杂草化除技术的应用效果   总被引:3,自引:1,他引:2  
对江苏省淮安市旱直播稻田杂革进行化除技术示范试验。结果表明,对直播稻田杂草防除应坚持化除为主、人工防除为辅的“一封二杀三补”策略,其中土壤封闭处理尤为重要。目前主体除草剂品种有丁草胺、二氯喹林酸、苄嘧磺隆、灭草松、2甲4氯等,恶草酮、氯氟毗氧乙酸对莎草科杂草防效较差。  相似文献   

8.
采用QuEChERS法结合超高效液相色谱-串联质谱法(UPLC-MS/MS)建立了玉米及其土壤中同时检测烟嘧磺隆、莠去津和氯氟吡氧乙酸残留的分析方法。样品采用乙腈(含体积分数为2%的甲酸)提取,基质固相分散净化后,用UPLC-MS/MS外标法检测定量。结果表明:该方法具有灵敏度高、简便、快速等优点;在0.01~1.0 mg/L质量浓度范围内,3种除草剂的仪器响应值与其质量浓度呈良好线性相关,相关系数大于0.990 6;玉米和土壤样品中3种除草剂的添加水平在0.02~0.5 mg/kg时,平均回收率均为78.9%~117.7%,日内相对标准偏差(RSD)均小于11.6%,日间 RSD 均小于13.9%。 3种除草剂在玉米籽粒、玉米植株和土壤中的定量限(LOQ)均小于7.1μg/kg。  相似文献   

9.
采用高效液相色谱(HPLC)法研究了0.2%苄嘧磺隆·丙草胺颗粒剂在稻田环境中的消解动态和最终残留。稻田水、谷壳、稻秆和水稻植株样品用二氯甲烷提取,土壤样品用V(二氯甲烷):V(甲醇)=9:1的混合液提取,糙米样品用V(二氯甲烷):V(甲醇)=7:3的混合液提取后再用二氯甲烷萃取;HPLC法测定。结果表明:当添加水平在0.05~1 mg/kg(或mg/L)时,苄嘧磺隆和丙草胺的平均回收率均在75%~103%之间,相对标准偏差(RSD)为1.6%~13%;苄嘧磺隆和丙草胺的检出限(LOD)均为0.02 mg/L,最小检出量均为4.0×10-10 g,在稻田水中的最低检测浓度(LOQ)均为0.001 mg/L,在稻田土壤中的LOQ均为0.005 mg/kg,在水稻植株、谷壳和糙米中的LOQ均为0.01 mg/kg。在水稻移栽后5~7 d,采用直接撒施法在高剂量(270 kg/hm2,其中苄嘧磺隆有效成分为67.5 g/hm2,丙草胺有效成分为472.5 g/hm2)下施药1次的消解动态试验结果表明:在稻田水、土壤和水稻植株中,苄嘧磺隆的消解半衰期分别为5.06~5.83 d、9.76~11.55 d和4.52~4.82 d,丙草胺的消解半衰期分别为5.94~6.45 d、7.70~9.90 d和4.11~4.89 d。分别按低剂量(180 kg/hm2,其中苄嘧磺隆有效成分为45 g/hm2,丙草胺有效成分为315 g/hm2)和高剂量(270 kg/hm2)施药1次,在正常收获期收获的糙米中均未检出苄嘧磺隆和丙草胺残留。  相似文献   

10.
除草剂防除狗牙根草坪阔叶杂草试验   总被引:2,自引:0,他引:2  
应用L9(34)正交表设计方案对56%2甲4氯钠、14%水花生净乳油及10%新得力三种除草剂混用的最佳配比,防除狗牙根草坪阔叶杂草,可扩大杀草谱,增强药效,降低残留。56%2甲4氯钠单剂防除猪殃殃的效果不理想,但与10%新得力混用,防除效果大大提高。  相似文献   

11.
Two Alisma plantago‐aquatica biotypes resistant to bensulfuron‐methyl were detected in rice paddy fields in Portugal’s Mondego (biotype T) and Tagus and Sorraia (biotype Q) River valleys. The fields had been treated with bensulfuron‐methyl‐based herbicide mixtures for 4–6 years. In order to characterize the resistant (R) biotypes, dose–response experiments, absorption and translocation assays, metabolism studies and acetolactate synthase (ALS) activity assays were performed. There were marked differences between R and susceptible (S) biotypes, with a resistance index (ED50R/S) of 500 and 6.25 for biotypes Q and T respectively. Cross‐resistance to azimsulfuron, cinosulfuron and ethoxysulfuron, but not to metsulfuron‐methyl, imazethapyr, bentazone, propanil and MCPA was demonstrated. No differences in the absorption and translocation of 14C‐bensulfuron‐methyl were found between the biotypes studied. Maximum absorption attained 1.12, 2.02 and 2.56 nmol g−1 dry weight after 96 h incubation with herbicide, for S, Q and T biotypes respectively. Most of the radioactivity taken up by the roots was translocated to shoots. Bensulfuron‐methyl metabolism in shoots was similar in all biotypes. The R biotypes displayed a higher level of ALS activity than the S biotype, both in the presence and absence of herbicide and the resistance indices (IC50R/S) were 20 197 and 10 for biotypes Q and T respectively. These data confirm for the first time that resistance to bensulfuron‐methyl in A. plantago‐aquatica is target‐site‐based. In practice, to control target site R biotypes, it would be preferable to use mixtures of ALS inhibitors with herbicides with other modes of action.  相似文献   

12.
作物种类对根际土壤中丁草胺降解的影响   总被引:6,自引:0,他引:6       下载免费PDF全文
研究了根际和非根际土壤中除草剂丁草胺的降解。结果表明,棉花、水稻、小麦和玉米的种植明显促进丁草胺的降解,15 mg/kg丁草胺的降解半衰期缩短26.6%~57.2%,这种促进作用与作物种类有关,玉米、小麦、水稻、棉花依次增强。50 mg/kg丁草胺的降解有所受抑制,但作物种植仍显示良好的促进作用。作物根际丁草胺降解菌的测定结果显示,根际土壤中丁草胺降解菌的数量大于非根际土壤,作物种植对丁草胺降解的促进作用源于根际丰富的降解菌。  相似文献   

13.
二甲四氯 (MCPA) 是铁铝土区域广泛使用的一种除草剂,生物毒性大。吸附是控制MCPA在土壤中迁移/转化的关键过程。本研究建立了以C18为色谱柱、V(甲醇):V[水 (乙酸调pH值至2.5)] = 80 : 20为流动相、PDA为检测器 (检测波长280 nm) 的MCPA高效液相色谱检测方法,并结合批量平衡法评估MCPA在铁铝土中的吸附特征。结果表明:在0.5~40 mg/L内,MCPA的质量浓度与对应的峰面积间呈良好线性关系 (R2 = 0.999 9),检出限为0.2 mg/L,定量限为0.5 mg/L;回收率为98%~103%,相对标准偏差为3.5%~4.0%,适用于MCPA吸附试验的测定。铁铝土对MCPA的等温吸附过程符合Freundlich模型,吸附自由能△G<0,|△G|为9.34~14.73 kJ/mol,是一个自发的、非均质的、多层的物理吸附过程。吸附常数Kf值在0.85~4.24 L/kg之间,属于难吸附污染物,对地下水具有环境风险。不同铁铝土对MCPA的吸附作用受土壤pH值、有机质、矿物影响,表现为水稻土>暗红湿润铁铝土>简育湿润铁铝土。氢键结合、偶极间作用是吸附发生的关键作用力。  相似文献   

14.
5种除草剂防除旱直播稻田杂草比较试验   总被引:3,自引:0,他引:3  
42%噁草·丁草胺EC1 500 mL/hm2对鳢肠的防效为82%,对禾本科杂草、大多数阔叶杂草及莎草均有良好的防除效果,防效均达100%;33%二甲戊灵EC 2 250 mL/hm2对旱莲草的防效为64.7%,对禾本科杂草和部分阔叶杂草及莎草的防效均在86%~100%之间;30%苄·丁WP2 250 g/hm2和35%苄嘧.丙草胺WP 900 g/hm2对阔叶杂草和莎草科杂草的防效较好,但对禾本科杂草的防效较差;30%丙草胺EC1 800 mL/hm2对稻田多种杂草的防效均低于63%。  相似文献   

15.
Forty-eight populations of Tripleurospermum inodorum (L.), Schultz Bip. (scentless mayweed) were collected from southern Britain and northern France between 1970 and 1972 and screened simultaneously for resistance to the herbicides ioxynil and MCPA. The mean fresh weights per plant in different population samples sprayed with ioxynil at 28 mg/m2 a.i. ranged from 2·2 to 39·5% of those of the corresponding controls, with a mean for all populations of 20·0 ± 1·09%, and the mean fresh weights per plant in different population samples sprayed with MCPA at 175 mg/m2 a.e. ranged from 10·3 to 60·1% of those of the corresponding controls, with a mean for all populations of 43·0 ± 1·60%. Resistance to ioxynil differed significantly between populations from different geographic areas but showed no correlation with spraying history. Resistance to MCPA also differed significantly between populations from different geographic areas, and showed a strong positive correlation with ioxynil resistance, but MCPA resistance was significantly greater in populations with a history of heavy spraying than in other populations. Spray retention and other physical characteristics were measured in six populations, but showed no correlation with herbicide resistance. It is suggested that most of the differences in herbicide resistance between populations of T. inodorum are side effects of genotypic differentiation in physiological characters not directly related to herbicide resistance, but that there has been some direct selection for resistance to MCPA.  相似文献   

16.
In four field experiments begun in 1963, each of four herbicides was applied to plots planted wilh the same crop each year. The annual treatments were: MCPA at 17 kg/ha to barley (Hordeum sativa Jess) and wheat (Triticum aestivum L.) at growth stage 15. tri-allate at 17 kg/ha pre-emergcnce to barley and wheat, simazine at l7kg/ha pre-emergence to maize (Zea mays L.) and linuron in two applications of 084 kg/ha pre- and post-emergence to carrots (Daucus carota L.). MCPA did not affect growth or yield of either barley or wheat. In general tri-allate also did not aftect the crops although wheat yield was depressed in 1978, wheat 1000 grain weight was reduced in 1972 and barley germination percentage was increased in 1973. Simazine did not influence the height, yield or appearance of maize. Linuron normally produced no effect on carrot yield, density and size. However, in 2 years when the post-emergence application was late, density but not yield was lower than in control plots. There was no accumulation of residues of any of these compounds in the soil. Rates of loss were similar to those predicted on ihe basis of laboratory experiments. In a fifth experiment these herbicides were applied twice per year (3 times in the case of linuron) at double the rales above on each occasion to bare plots. These applications ceased in 1968 (1969 for MCPA) but residues were monitored until 1972 except in the case of MCPA. Disappearance rates were similar to those in the cropped plots and residues were largely confined to the top 10 cm. The plots treated with MCPA had developed an enhanced ability lo degrade il prior to 1968. This persisted for 5 years after the final application.  相似文献   

17.
A. LUNDKVIST 《Weed Research》1997,37(5):361-371
The influence of weather on the efficacy of dichlorprop-P/MCPA and tribenuron-methyl on annual weeds in spritig barley was studied in the field during 4 years at six locations in southern Sweden. The herbicides were applied at one-eighth to three-quarters of the full dose at three application times with approximately 6-day intervals. Weather stations, placed in the experiments, recorded climatic data, Maximum herbicide efficacy was obtained when spraying 1 week after the cotyledon stage with half or three-quarters of the recommended dose. Dose-response curves were estimated and the ED80 doses were calculated. On average, the herbicide dose required to obtain an effect of 80% was about 40% of the recommended dose. The influence of weather was analysed for seven different periods: 7 and 2 days before and after herbicide application, 1 day before and after application, and the day of herbicide treatment. The most pronounced eftects of weather were found for the day of and the day before herbicide application, revealing the strong influence of weather on herbicide uptake and plant metabolism. High air tetnperature and low global radiation during the day of treattnent reduced the ED80 dose of dichlorprop-P/MCPA, whereas the ED80 dose of tribenuron-methyl increased. For both herbicides, precipitation and high soil temperature increased the ED80 dose, which reflects the importance of rain on herbicide uptake and the effect of soil temperature on plant growth. The R2 values were higher in the analyses of dichlorprop-P/MCPA than of tribenuron-methyl, indicating that the effect of dichlorprop-P/MCA was more weather-dependent than that of tribenuron-methyl. Separate analyses of the ED80 doses for Brassica napus L., Chenopodium, album L. and Stellaria media (L.) Vill. generally resulted in increased R2 values. but otherwise gave results similar to those for the total weed population. Although the analyses revealed significant effects of indivtdual weather factors on herbicide efficacy, it was not possible to discern a consistent and causal relationship between weather and herbicide performance.  相似文献   

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