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1.
快速测定果蔬中农药残留量的方法研究   总被引：34，自引：0，他引：34  
用自行研制的便携式农药残留速测仪，对果，蔬中农药残留毒性进行快速检测，可以直接显示有机磷和氨基甲酸酯类药对乙酰胆碱酶的抑制率，确定农药残留毒性水平。  相似文献   

2.
随着我国经济水平的不断提高,农产品生产的重点逐渐从数量转移到质量安全方面。目前,国内农产品质量安全检测的主要是蔬菜中有机磷和氨基甲酸酯类二大类农药残留。国内用于农药残留的常用检测方法有气相色谱法和酶抑制法。气相色谱法成本高,适合用于定性定量检测;酶抑制法操作简便、成本低廉,适合用于定性的快速检测。实现对农产品中蔬菜、水果的农药残留监督,需要推行快速、简便、准确的检测方法,才能达到有效监控的目的。基于此,利用广东省开平市农产品质量监督检测站的技术力量和仪器设备,对目前华南地区占主流地位的4种农药残留快速检测仪器所应用的技术进行了一系列的试验,从而筛选出适用于当前情况的技术,进行推广应用,并调查验证推广应用的效果。  相似文献   

3.
农产品质量安全快速检测试剂盒评价方法研究   总被引：1，自引：0，他引：1  
通过对农产品质量安全检测监管工作中所使用的快速检测产品的梳理,将快速检测试剂盒分为定量型、定性型、非定量非定性型试剂盒3类,分别以酶联免疫快速检测试剂盒、胶体金免疫层析法快速检测试剂盒和植物性样品中有机磷和氨基甲酸酯类农药残留的酶抑制-比色法快速检测试剂盒为例,根据各类试剂盒的特征和检测目的,从准确度、精密度、重复性、检出限、定量限、线性范围、特异性、基质效应、完成批量样品所用的时间、前处理过程中使用的仪器数量、前处理方法的难易程度、对农药的敏感性等方面对3类试剂盒的评价方法进行了初步探索和研究。  相似文献   

4.
为探讨麦麸酯酶在农残快速检测中应用的可行性,通过比色法研究了酶抑制法检测农残时表面活性剂对固蓝B盐显色体系的增敏作用及麦麸酯酶对乐果、敌敌畏、叶蝉联、西维因、丁硫克百威和甲基对硫磷等6种农药的灵敏度和最低检测限。结果表明,阴离子表面活性剂SDS在麦麸酯酶活性测定中具有增敏作用,当浓度为4.0%时可使显色体系相对吸光度值增加152.76%;叶蝉散对麦麸酯酶的最佳抑制时间为40min,其余5种农药均为30min。麦麸酯酶对6种农药的灵敏度大小顺序为:敌敌畏叶蝉散西维因甲基对硫磷丁硫克百威乐果,IC_(50)分别为0.136、0.375、0.641、1.366、2.361、2.651mg·L~(-1)。经溴水氧化的甲基对硫磷对麦麸酯酶的敏感性显著提高,其IC_(50)值达0.089mg·L~(-1)。综上所述,麦麸酯酶在快速检测有机磷及氨基甲酸酯类农药方面具有较高的灵敏度,且来源广泛,可满足酶抑制法用酶需要。本研究丰富了麦麸酯酶在农药残留快速检测中的应用。  相似文献   

5.
辐照降解中草药中氨基甲酸酯和有机磷残留   总被引：2，自引：0，他引：2  
为了对中草药中残留农药的去除提供新的方法和依据,本文研究了辐照剂量、含水量等不同因子对人参中氨基甲酸酯及有机磷农药去除率的影响,同时探讨了白茯苓等不同中草药基质中两类农药同一剂量辐照的去除效果。结果表明:电子束辐照可有效加速氨基甲酸酯和有机磷农药残留的降解;低剂量辐照下的农药降解不如高剂量的效果明显,农药辐照降解率随着辐照剂量的增大呈增加的趋势,并在4～10 kGy区间内有波动;在不同的中草药基质中,有机磷农药降解效果普遍优于氨基甲酸酯农药。  相似文献   

6.
为快速检测农产品农药残留，开发了基于酶抑制法的农产品农药残留快速检测系统。该检测系统由固体光源、样品池、单片机测量电路板及微机等组成，通过测量经酶抑制反应后样品液的吸光度值实现农产品中农药残留的快速检测。研究了吸光度随反应时间的变化关系、温度对酶活性的影响及农药残留浓度与酶抑制率的关系。结果表明吸光度随反应时间逐渐增加，反应前期增速快，线性度好，适合测量；酶在20～40℃时具有最佳的活性，灵敏度高；农药残留对酶的抑制作用明显，当抑制率高于70%时可判定农药残留超标。  相似文献   

7.
为研究NY/T 761-2004(农业行业标准)用于蔬菜有机磷农药多残留检测中的样品基质干扰问题,根据NY/T 761-2004分析众多蔬菜样品,结合气质联用技术,评估蔬菜样品基质对有机磷农药多残留分析的干扰。结果表明,用NY/T 761-2004检测蔬菜有机磷农药多残留时,绿叶菜类、白菜类、瓜类、茄果类、豆类、薯芋类和根菜类蔬菜几乎没有样品杂质峰,有机磷农药测定不受干扰;甘蓝类蔬菜(如紫甘蓝、甘蓝和西兰花等)有显著的样品杂质峰,敌敌畏、甲胺磷、甲拌磷和甲基毒死蜱等测定常受干扰;葱蒜类蔬菜(如蒜、葱和韭菜等)有较强的样品杂质峰,有机磷农药多残留测定无法进行。  相似文献   

8.
为了建立谷物、油料和植物油中氨基甲酸酯类农药残留的超高效液相色谱-串联质谱(UHPLC-MS/MS)快速检测技术,本研究探明了玉米、小麦、糙米、花生、大豆和大豆油为基质的样品前处理条件,采用乙腈提取,盐析后乙二胺N-丙基硅烷(PSA)净化,正离子多反应监测(MRM)模式测定。结果显示,克百威、甲萘威、抗蚜威等28种氨基甲酸酯农药在各自的线性范围内线性关系良好,线性相关系数均大于0.996;添加回收结果显示, 28种农药在0.02、 0.10和0.50mg/kg 3个加标水平下的平均回收率为65.2%～122.8%,相对标准偏差(RSDs)为0.4%～19.1%,方法定量限为0.01～0.02mg/kg。该方法简便、快速,灵敏度高,适用于粮食、油料和植物油中氨基甲酸酯类农药残留的快速筛查检测。  相似文献   

9.
电化学免疫传感器快速检测农产品中的毒死蜱   总被引：2，自引：1，他引：1  
研究了一种无标记的电化学免疫传感器,用于农产品中的毒死蜱农药残留的快速检测。将毒死蜱人工抗原作为生物识别元件固定在金电极的表面,采用间接竞争法原理,样品中的被测组分与电极上的固定化包被抗原竞争性结合溶液中的抗体。抗体抗原结合反应通过电化学阻抗谱和石英晶体微天平进行表征。将该免疫传感器用于检测青菜、苹果等农产品中的毒死蜱农药残留。结果表明,此免疫传感器灵敏度好、准确度高;对毒死蜱农药的检测限为0.01μg/mL,回收率大于85%,检测时间小于1 h,变异系数小于5%,传感器经过再生处理后能重复使用,经济性较好。该研究可为实现快速检测农产品中农药残留传感器的商品化提供参考。  相似文献   

10.
随着人民生活质量的提高,蔬菜水果中农药残留问题日益受到广泛关注。果蔬中农药残留检测工作成为各级农业推广站和食品安全监测部门的重要工作之一,而农药残留检测过程复杂,技术含量高,对基层工作者是一种较大考验。提高检测的准确性是这项工作真正落到实处并取得成效的关键。基于此,针对果蔬中氨基甲酸酯类农药残留的化学检测法研究进展进行综述,为提高检测准确性提供一些参考。  相似文献   

11.
【目的】以富士（Fuji）、 秦冠（Qinguan）嫁接在平邑甜茶（Malus hupehensis Rehd.）上的当年生盆栽苗为试验材料,采用砂培方法,研究了缺氮胁迫和干旱对富士和秦冠生长情况、 光合参数、 植株各部位氮磷钾含量及氮素利用效率的影响,分析比较了低氮干旱条件下富士和秦冠生长及氮素利用的差异,以期为果树生产高效肥水利用提供理论指导。【方法】试验共设四个处理: 正常氮正常水（ZZ）、 低氮正常水（DZ）、 正常氮干旱（ZG）、 低氮干旱（DG）。氮素和水分均设置两个水平,分别为正常氮（6 mmol/L NO-3-N）、 低氮（0.3 mmol/LNO-3-N）、 正常供水（保持盆中砂子相对含水量为饱和含水量的80%~85%）、 干旱处理（保持盆中砂子相对含水量为饱和含水量的60%~65%）。【结果】富士和秦冠的生物量（茎和叶）、 株高茎粗等生长指标以及光合速率、 气孔导度、 蒸腾速率均为正常氮正常水（ZZ）＞低氮正常水（DZ）＞正常氮干旱（ZG）＞低氮干旱（DG）,并且相对应处理下秦冠的以上指标均高于富士;正常供水下,缺氮处理使富士、 秦冠的根冠比比正常氮处理均有所增加,富士提高了2.05%,秦冠提高了22.40%。富士和秦冠的氮、 磷、 钾含量均表现出正常氮正常水（ZZ）＞低氮正常水（DZ）＞正常氮干旱（ZG）＞低氮干旱（DG）; 氮、 钾元素含量在植株各部位的分布顺序依次是叶＞根＞茎,磷元素则是根＞叶＞茎;光合氮素利用效率（PNUE）和氮素利用效率表现为秦冠处理之间差异极显著,富士处理之间差异不显著;秦冠的PNUE和NUE明显高于富士,在低氮正常水（DZ）处理下,秦冠氮肥利用率比富士高42.07%,在低氮干旱（DG）处理下高64.14%;低氮胁迫下富士和秦冠的NUE显著提高,并且秦冠提高的幅度高于富士。【结论】施用氮肥能够显著提高富士与秦冠的干物质量,同等水肥条件下,秦冠生长优于富士;水分亏缺会减少叶片对氮的吸收,干旱条件下适度增施氮肥,可提高果树的抗旱能力;低氮干旱胁迫下秦冠的生长指标、 光合指标及氮素利用效率指标均优于富士,表现出较强的抗低氮干旱胁迫的能力。  相似文献   

12.
Laser-induced breakdown spectroscopy (LIBS) is a new technique for the analysis of plant material. This study investigates the application of LIBS to pasture-based plant samples. The LIBS measurements were obtained from pelletized pasture samples (100 samples) that had been also analyzed by inductively coupled plasma–optical emission spectroscopy (ICP-OES) following microwave digestion for calibration and comparison purposes. Comparisons for elements sodium (Na), potassium (K), magnesium (Mg), calcium (Ca), manganese (Mn), iron (Fe), copper (Cu), zinc (Zn), boron (B), phosphorus (P), and sulfur (S) showed that LIBS could be used for almost all the standard profile total elements with concentrations down to low mg/kg levels (observed error of Na: 0.024 percent, K: 0.18 percent, Mg: 0.016 percent, Ca: 0.073 percent, P: 0.017 percent, Mn: 31 mg/kg, Fe: 150 mg/kg, Zn: 6.6 mg/kg, and B: 1.1 mg/kg). Elemental analysis at less than mg/kg levels was not possible using LIBS. The elements S and Cu were particularly difficult to analyze with reliability using LIBS at the concentration levels found in the plant samples. Replacing microwave digestion and subsequent ICP analysis with a direct analysis of dried plant samples using LIBS has the potential to improve the productivity and reduce the cost of testing.  相似文献   

13.
正The Center for Agricultural Resources Research(CARR),the Institute of Genetics and Developmental Biology(IGDB),Chinese Academy of Sciences,invites applicants for several research group leader positions.CARR is one of the research organizations in Chinese Academy of Sciences(CAS).We seek nominations and applications from individuals who have expertise and a record of accomplishment in research areas related to ecology,agro-hydrology,  相似文献   

14.
The responses of tallgrass prairie plant communities and ecosystem processes to fire and grazing are well characterized. However, responses of invertebrate consumer groups, and particularly soil-dwelling organisms, to these disturbances are not well known. At Konza Prairie Biological Station, we sampled soil macroinvertebrates in 1994 and 1999 as part of a long-term experiment designed to examine the effects and interactions of annual fire, mowing, and fertilization (N and P) on prairie soil communities and processes. For nearly all taxa, in both years, responses were characterized by significant treatment interactions, but some general patterns were evident. Introduced European earthworms (Aporrectodea spp. and Octolasion spp.) were most abundant in plots where fire was excluded, and the proportion of the total earthworm community consisting of introduced earthworms was greater in unburned, unmowed, and fertilized plots. Nymphs of two Cicada genera were collected (Cicadetta spp. and Tibicen spp.). Cicadetta nymphs were more abundant in burned plots, but mowing reduced their abundance. Tibicen nymphs were collected almost exclusively from unburned plots. Treatment effects on herbivorous beetle larvae (Scarabaeidae, Elateridae, and Curculionidae) were variable, but nutrient additions (N or P) usually resulted in greater densities, whereas mowing usually resulted in lower densities. Our results suggest that departures from historical disturbance regimes (i.e. frequent fire and grazing) may render soils more susceptible to increased numbers of European earthworms, and that interactions between fire, aboveground biomass removal, and vegetation responses affect the structure and composition of invertebrate communities in tallgrass prairie soils.  相似文献   

15.
Abstract

A 3-year study was carried out to investigate quality parameters in 14 tree fruit and berry species grown in southern Norway. The species were blueberry, apple, aronia, sour cherry, sweet cherry, red raspberry, strawberry, blackcurrant, gooseberry, red currant and elderberry, harvested along with wild bilberry, cloudberry and lingonberry. Significant differences between species were identified for all quality parameters. The coefficient of variation between species was lowest for pH (12.5%), dry matter (18.9%) and soluble solids (25.3%), followed by titratable acids (59.3%), total phenolics (83.8%), antioxidant capacity FRAP (85.7%) and antiradical power by the DPPH-assay (97.8%), total monomeric anthocyanins (132%) and ascorbic acid (137%). Average coefficient of variation within species were lower and ranged from 4 (pH) to 62% (ascorbic acid). Only the FRAP values were significantly affected by harvesting year with lower levels in 2004 than in 2005 and 2006. There were significant interactions between species and harvesting year for dry matter, soluble solids, pH, ascorbic acid and FRAP. The results indicate generic ranges in composition within species independent upon growing location and climate, and the composition of the tree fruits and berries is not likely to deviate from these ranges. It is concluded that desirable composition of tree fruits and berries and their products should primarily be achieved by selection among species rather than searching fors broadened variation within individual species.  相似文献   

16.
Potassium (K) fixation and release in soil are important factors in the long-term sustainability of a cropping system. Changes in K concentration and characteristics of K fixation and release in rhizosphere and nonrhizosphere soils in the rapeseed (Brassica napus L.)–rice (Oryza sativa L.) rotation were investigated using a rhizobox system. The concentrations of different forms of K in both rhizosphere and nonrhizosphere soils decreased with plants compared to without plants, regardless of K fertilizer application. Potassium uptake by crops mainly came from the rhizosphere soil. In the treatment without K fertilizer (–K), the main form of K supplied by the soil to the crops was 1.0 mol L?1 nitric acid (HNO3) nonextractable K, followed by nonexchangeable K, and then exchangeable K. In the treatment with K fertilizer (+K), the main K forms supplied by the soil to the crops were exchangeable K and nonexchangeable K. The amount and rate of K fixation after one cycle of the rapeseed–rice rotation was greater in rhizosphere soil than in nonrhizosphere soil. The amount and rate of K fixation of soil in the +K treatment were significantly less than in the –K treatment. The cumulative amounts of K released with 1.0 mol L?1 ammonium acetate (NH4OAc) and 1.0 mol L?1 HNO3 extraction increased with the increasing numbers of extractions, but the K-releasing power of soil by successive extraction decreased gradually and finally became almost constant. The release of K was less in rhizosphere soil than in nonrhizosphere soil. The release of K in the +K treatment was similar to that in the –K treatment in rhizosphere soil, but the K release in nonrhizosphere soil was greater with the +K than the –K treatment. Overall, the information obtained in this study will be helpful in formulating more precise K fertilizer recommendations for certain soils.  相似文献   

17.
Staff members of the Department of Botany of Palacký University in Olomouc and Gene Bank Department – Workplace Olomouc, Research Institute of Crop Production in Prague, Czech Republic, conducted an expedition in seven European countries (Austria, Czech Republic, France, Germany, Italy, the Netherlands, Switzerland) in August/September 1999 to collect wild Lactuca spp. germplasm and study its geographic distribution, ecology and biodiversity. During the mission, more than 600 locations were visited resulting in the collection of 602 seed samples (accessions) of wild Lactuca species and 13 seed samples of related genera (Chondrilla and Mycelis). Lactuca serriola f. serriola, L. serriola f. integrifolia, L. saligna and L. viminea subsp. chondrilliflora were prevalent in southern Europe (Italy, France), however, only L. serriola was common in central and western Europe (Austria, Czech Republic, Germany, Netherlands, Switzerland). The greatest diversity of Lactuca species was found in France, where also the most seed samples (165) were collected. The most characteristic habitats with a high density of Lactuca spp. populations were observed along roads and highways, grassy ditches, ruderal communities, and dust-heaps. Natural infections by powdery mildew (Erysiphe cichoracearum) and downy mildew (Bremia lactucae) on some wild Lactuca spp. were observed. Recent observations concerning the geographic distribution, population structure, habitats, and natural occurrence of diseases of Lactuca spp. are discussed. This assemblage of genetic resources of Lactuca spp. can serve as the basis of future studies of species diversification, spatial population structure, plant microevolution, domestication processes, and genetic variability of host-parasite interactions.  相似文献   

18.
Inoculation of wheat seedlings with the plant growth-promoting bacterium Azospirillum brasilense Cd was immobilized in alginate microbeads and, without applying any stress, significantly increased the quantity of several photosynthetic pigments, such as chlorophyll a, chlorophyll b, and the auxiliary photoprotective pigments violaxanthin, zeaxanthin, antheroxanthin, lutein, neoxanthin, and β-carotene. This resulted in greener plants with no apparent visible stress. After monitoring the quantity of photosynthetic pigments for 4 weeks, we observed that inoculated plants had higher quantities of pigments in shoot and stem. The greatest difference in the quantity of all pigments between inoculated and noninoculated plants occurred in the first week of growth. Regardless of treatment, the quantity of pigments in stems was three to four times less than the quantity of these pigments in shoots. Application of Azospirillum, either as liquid inoculant or as alginate microbeads, did not alter the positive effect of the bacteria on pigment production or the positive response of the plants towards A. brasilense Cd inoculation.  相似文献   

19.
We examined the community composition of microbes that colonized atrazine-containing beads buried in agricultural soils that differed in atrazine treatment history. Bacterial abundance was 5-40-fold greater in atrazine-fortified beads. In beads containing 20 mg atrazine kg−1 buried in soil with a history of atrazine application (conditioned soil), the abundance of Actinobacteria increased approximately 80-fold whereas in control soil, Actinobacteria were enriched only 10-fold and the gamma-Proteobacteria and Planctomycetes increased by 60- and 25-fold, respectively. The gamma-Proteobacteria were enriched by 120- and 230-fold in beads containing 200 mg atrazine kg−1 in conditioned and control soil, respectively. The results demonstrate that BioSep® beads are a suitable matrix for recruiting a diverse subset of the bacterial community involved in atrazine degradation.  相似文献   

20.
We have studied the effect of anaerobically digested (ADMSW) and composted municipal solid waste (CMSW) on mineralization and foodweb dynamics to verify the hypothesis that ADMSW would immobilize N right after addition to soil in contrast to addition with CMSW. Another hypothesis was that the mesofauna (enchytraeids and microarthropods) would stimulate N release from the decomposer community. We measured excretion of -N and urea-N from the mesofauna and hypothesized that enchytraeids would release urea. ADMSW and CMSW were amended to pots with sandy loam and barley. The pots were divided into treatments with or without mesofauna. Mesofauna, plant N and biomass, soil N and ergosterol (fungal biomass) were measured over a 113-day period of four equidistant samplings. Soil respiration, N mineralization and N release by the mesofauna were modelled from concurrent studies. ADMSW- and CMSW-treated soils initially (<20 days) immobilized N. The amendments did not increase plant growth substantially, and this was probably due to N-limitation in the early stages of plant growth. Enchytraeid abundance was about three times higher in ADMSW- than CMSW-treated soils, indicating that ADMSW contained more labile compounds, bacteria, and microfauna. The mesofauna did not affect N-content, but the cumulated -N excreted by the mesofauna was estimated to be substantial and about one-fifth of total plant N in ADMSW. An explanation for this discrepancy might be that in the absence of the mesofauna, other members of the detrivore and microbivore community performed the mesofauna’s function. Neither enchytraeids nor microarthropods excreted urea.  相似文献   

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