摘要
二氯吡啶酸是一种吡啶类除草剂,主要用于防除禾本科作物及多种阔叶作物中的阔叶杂草。本文采用反相高效液相色谱(HPLC)分析测定二氯吡啶酸在油菜田土壤中和植株上的残留动态及收获期土壤和油菜籽粒中二氯吡啶酸的残留量,并对二氯毗啶酸在土壤-水中的吸附解吸特性进行了研究。为农药品种登记,制定最高残留限量(MRL)标准,以及合理使用提供理论依据。
土壤样品前处理采用传统的振荡和离心法,以氢氧化钠水溶液提取,通过调节水溶液酸碱度用乙酸乙酯萃取,最后将提取物收集浓缩,选择Zorbaxsb-C_(18)柱以甲醇和醋酸酸化的水溶液为流动相,用紫外检测器在285nm处检测。该方法简单,易于操作。而油菜植株和籽粒样品前处理采用组织捣碎、振荡和离心法,以氢氧化钠水溶液提取,提取后同样调解提取液的酸碱度,再用乙酸乙酯萃取,将提取物收集浓缩,过层析柱净化,最后将洗脱液浓缩,进行高效液相色谱(HPLC)分析。
采用添加法测定回收率。土壤、油菜植株和籽粒添加水平0.10gg/ml-1.00μg/ml,土壤平均回收率为77.3%-92.0%,植株平均回收率为81.0%-92.0%,籽粒平均回收率为73.0%-75.6%。在上述添加水平范围内,二氯吡啶酸的线性关系良好。土壤、油菜植株和籽粒中二氯吡啶酸的最小检出浓度均为0.01mg/kg。
通过在吉林省2004年、2005年两年田间试验对二氯吡啶酸在以338g(a.i)/hm~2用量处理的土壤和油菜样品作残留动态分析。降解过程符合一级反应动力学模式C=C_0e~(-kt)。在土壤中两年的动态方程分别是:2004年,C=0.3676e~(-0.1464t),半衰期为4.74天;2005年,C=0.2974e~(-0.1840t),半衰期为3.76天。在油菜植株中两年的动态方程是:2004年,C=2.5899e~(-0.06852t),半衰期为10.11天:2005年,C=1.3292e~(-0.08169t),半衰期为8.49天。二氯吡啶酸在收获期植株和籽粒中均未检出。结果表明:二氯吡啶酸在油菜植株和土壤中均易降解,在植株中降解速度比较慢。
土壤对二氯吡啶酸的吸附解吸试验,选取了有机质含量不同的三种类型土壤:草甸土、白浆土和黑钙土。采用经典的振荡平衡法进行研究。在5克土壤中加入25ml不同浓度的二氯吡啶酸水溶液。在25±2℃水浴中振荡,24小时后取上清液进行液相色谱(HPLC)法分析。结果表明,二氯吡啶酸在土壤上吸附解吸与土壤的理化性质密切相关,低:百机质的土壤吸附能力较弱;其吸附、解吸均可用Freundlich方程描述。
Clopyralid is a selective post-emergence herbicide controlling broad-leaved weeds. The determination and degradation of clopyralid in soil and oilseed were studied. The soil samples were macerated with aqueous sodium hydrogen. The slurry was tumbled and centrifuged. The solution phase containing clopyralid was clean up with ethyl acetate. Then an aliquot(15ml) of the ethyl acetate collected was evaporated just to dryness by rotary evaporation at 40 ℃. The HPLC analysis was performed with Zorbax C_(18) column. Clopyralid was elute with methanol-glacis acetic acid solution mixtures. The plant samples and seeds of oilseed were extracted with aqueous sodium hydrogen to attain clopyralid. And tumbled, centrifuged, finally clean up with silica. The HPLC analysis is the same as the soil. The method was simple. On the level of 0.10-1.0μg/ml,the average recovery of clopyralid in soil ,plant and seed were 77.3%-92.0% , 81.0%-92.0%, 73.0%-75.6%, respectively. The minimum detectable concentration of clopyralid in soil, plant and seeds of oilseed were 0.01mg/kg.
The degradation of clopyralid in soil and plant of oilseed were studied by HPLC method and a 2-year field experiment in Jilin province. The soil and plant were treated with clopyralid at 338g(a.i)/hm~2. Sample the soil and plant at different time to do degradation dynamics analysis. The degradation procedure of clopyralid was correspond to the mathematic pattern, C=C_0e~(-kt). In soil, the dynamic equation in 2004 was c=0.3676e~(-0.1464t) and the half-life was 4.74d, and the dynamic equation in 2005 was c=0.2974e~(-0.1841t) and half-life was 3.76d. In the plant of oilseed, the dynamic equation in 2004 was c=2.5899e~(-0.06852t) and the half-life was 10.11d, and the dynamic equation in 2005 was c=1.3292e~(-0.08169t) and half-life was 8.49d Clopyralid was not detected in soil , plant and seeds of oilseed at harvest. The result showed that clopyralid was dissipated in soil rapidly and the degradation of clopyralid in plant was slowly than in soil.
The adsorption and desorption of clopyralid by soil was studied by equilibrium method. Three different soil types were used in the study. Clopyralid solutions(25ml) of different density were added to soil (5g) and were shaker at 25℃,A HPLC method was carried out to detect the clopyralid amount in water after 24 hours. The result showed that the adsorption and desorption of clopyralid were mainly influenced by organic carbon content.
引文
[1] 苏少泉.除草剂作用靶标与新品种创新[M].北京化工出版社,2001.212-213.
[2] 苏少泉.中国农田杂草化学防治[M].北京:中国农业出版社,1996,105-107.
[3] 黄士忠 李治祥.农药的环境问题及发展趋向[J].国外农业环境保护,1990,33(2):21-23.
[4] 张一宾.高新技术在农药领域中的应用[J].农药,1992,31(4):9-10.
[5] 屠予钦.农药和化学防治前景广阔[J].农药,1992,35(5):6-8.
[6] 李治祥.农药的发展及其对环境的影响fJ].国外农业环境保护,1987,30(3):5-8.
[7] 阿.维.雅布洛科夫.施用农药的不良后果[J].国外农业环境保护,1991,34(1):9-12.
[8] 何康主编.中国农业百科全书(农药卷)[M].北京:农业出版社,1993,200-201.
[9] 张国生 郑瑞琴20%二氯吡啶酸可溶性液剂配方研究[J]浙江化工 2003,(34)4:11-12.
[10] Christine Ambrose. Margaret Boland .Scoping comments on Noxious and Invasive plant Control Project.Environmental Protection Center.2002.
[11] Caroline Cox. Herbicide factsheet :Clopyralid. Journal of pesticide reform. 1998, 18(4): 15-19
[12] Shang, C. Arshad, M.A. Sorption of clopyralid, dicamba and MCPC by two soils with conventional and no-till management.J.Soil Sci. 1998,78(1) 181-186.
[13] Hayes WC. Smith FA. John JA. et al. Teratologic evaluation of 3,6-Dichloropicolinic acid in rats and rabbits.J.Fundam Appl.Toxicol,1984, 4(1) :91-97.
[14] 中国农药信息网.
[15] 刘乾开 朱国念 新编农药使用手册[M]上海科学技术出版社,1999,412-413.
[16] Dow AgroSciences Clopyralid .a North American technical profile. Indianapolis. 1998: 5-7.
[17] Mumn.Mark D.Pestide toxicity, index for freshwater aquatic organisms. J. Water-Resources Investigation. 2001:4001-4077.
[18] Tan, Liang K. Humphries,David. Yeung,Paul Y.P.et al.Determinations of clopyralid,picloram, and silvex at low concentrations in soils by calcium hydroxide-water extraction and gas chromatography. J.Agric.Food chem. 1996,44(4): 1135-1143.
[19] Schuetz,S.Vedder, H. Duering,R.-A.. Weissbecher, B et al. Clopyralid dissipation in soil:investigations by GC-MS. J. Meded.-Fac.Landbouwkd.Toegepaste Biol.wet.1995:60,491-496.
[20] Schuetz, Stefan.Weibbecker, Bernhard.Hummel,Hans E. Gas chromatography-mass spectrometry analysis of the herbicide clopyralid in differentially cultivated soils. J .Environ.Toxicol.Chem. 1996,15(3):249-252.
[21] Schuetz,S. Vedder, H. Duering,R.-A et al.Analysis of the herbicide clopyralid in cultivated siols. J.Chromatogr.,A 1996:754(1+2),265-271.
[22] Crescenzi,Carlo.D'Ascenzo,Giuseppe.Corcia,Antonio Di et al.Multiresidue herbicide analysis in soil:subcritical water extration with an online sorbent trap. ,1 .Anal.Chem 1999,71(11):2157-2163.
[23] Kostowska,Barbara. Sadowski,Jerzy.Rola,Jozef. Results of lysometric reseach on the dislocation of some herbicides applied in the maize,spring wheat and field bean.Part Ⅱ Residues in leaching waters,soil and plants.J.Mater.Ses.Nauk,Inst.Ochr.Rosl. 1992,31(2): 147-151.
[24] Butz S.Stan H.-.I. Screening of 265 pesticides in water by Thin-Layer Chromatography with Automated Multiple Development. J. Anal. Chem. 1995, 67(3):620-630.
[25] Lange, Frank Thomas.Meier, Ulrike.Wenz,Michael et al.Automated ion-pair extration and ion-pair chromatography of highly polar micropollutants .J.Acta Hydrochim. Hydrobiol. 1995,23(1):6-12.
[26] Brumhard, B. Bergstroem ,L. F. Snel, Met al. Dissipation of clopyralid in soil under field conditions: lysimeter studies in Germany and Sweden .J. Meded.Fac.Landbouwwet.Rijksuniv.Gent. 1991,56(3a):887-900.
[27] Butz, S. Stan, H.-J. Determination of chlorophenoxy and other acidic herbicide residues in groined water by capillary gas chromatography of their alkyl esters formed by rapid derivatization using various chloroformates. J. Chromatogr. 1993,643(1-2):227-238.
[28] Stan,H-J. Heberer, Th. Automated recognition of target compounds at low levels in environmental samples by means of capillary gas chromatography-mass spectrometry with dedicated mass spectral libraries and the macro program AUTARG.H.Application to pesticides in groundwater samples. J.Chromatogr. 1993,653(1):55-62.
[29] Butz,S. Heberer, Th. Stan, H.-J. Determination of phenoxyalkanoic acide and other acidic herbicides at the low ppt level in water , applying solid-phase extraction with RP-C_(18) material . J.Chromatogr.A 1994,677(1):63-74.
[30] Schuetz,S. Weissbeeker, B.Wittig,Ch et al.Ultrasound enhanced derivatization and GC-MS analysis of clopyralid . J. Meded.-Fac.Landbouwkd. Toegepaste Biol.Wet. 1994,59(3b): 1415-1422.
[31] Joe,Arthur S. Hong:,Moo-Ki .Albert E. Analysis of 2,2,2-Trifluoroethyl derivatives of carboxylic acid herbicides by gas chromatography with mass-selective and electron capure detection. J.AOAC Int. 1995,78(6): 1459-1464.
[32] Snel, M. Almond, R.Scorer, D J. Dissipation of clopyralid in German soils under field conditions..J. Meded.Fac.Landbouwwet.,Rijksuniv. Gent. 1986,51(2A):227-234.
[33] 农药残留分析[M] 岳永德 中国农业出版社出版.2004.
[34] 农药残留量分析与检测[M]樊德方 上海科学技术出版社.1982.
[35] Eshak S. J.R.Phimster. The determination of clopyralid residues following post emergent application to oilseed rape in Geelong ,Victoria.Dow confidential information.
[36] Gaoloux, Michel P. Albert C.Jean C.Van Damme. Gas chromatographic determination of 3,6-dichloropicolinic acid residue dissipation in a soil .J.Agric.Food Chem. 1985,33(5):965-968.
[37] Hajslova J. Jehlickova Z. Pudil E.et al. Residues of clopyralid (3,6-dichloropicolinic acid) in strawberries and their changes. J, Nahrung. 1988,32(9):861-865.
[38] Lauren Denis R.H.Jack Taylor.Anisur Rahman.Analysis of herbicides dicamba,clopyralid and bromacil in asparagus by high-performauce liquid chromatography. J.Journal of chromatography, 1988,439(2): 470-475.
[39] 农业部农药检定所编 农药残留量使用检测方法手册(第一卷)中国农业科技出版社 1995.
[40] 中华人民共和国农业部 NY/T788-2004 中华人民共和国农业行业标准 农药残留试验准则 中国农业出版社 刘光学 乔雄梧 陶传江等,2004.7.1.
[41] 高健磊 李冰 范顺利等.农药废液中氧乐果及其中间体土壤吸附系数和降解速率的测定[J].河南科学,1998,(17)4:413-418.
[42] 沈阿林 崔转铃 姚同山.几种土壤对氟的吸附和解吸[J].植物营养与肥料学报,1997,(3)1:9-15.
[43] 郭晓冬 张雪琴 杨玲.甘肃省主要农业区土壤对磷的吸附与解吸特性[J].西北农业学报.1997,6(2):7-12.
[44] 龙新宪 倪吾钟 杨肖娥.菜园土壤锌的吸附-解吸特性研究[J].土壤通报,2002,(33)1:51-53.
[45] 杨炜春 王琪全 刘维屏.除草剂莠去津(atrazine)在土壤—水环境中的吸附及其原理[J]环境科学,2000,(21)4:94-97.
[46] 石利利 林玉锁 徐亦钢等.毒死蜱农药环境行为研究[J].土壤与环境,2000,9(1):73-74.
[47] 郭荣波 陈吉平 张青等 五种不同类型土壤中有机化合物土壤吸附系数的预测[J]色谱,2004,(22)1:57-60.
[48] 农药环境化学[M]刘维屏 化学工业出版社.2006.119-129.
[49] 农药环境毒理学研究[M]蔡道基 中国环境科学出版社,1999.
[50] 罗玲 欧晓明 廖晓兰.农药在土壤中的吸附机理及其影响因子研究概况[J].化工技术与开发,2004,(33)1:12-16.
[51] Bernhard M. Berger. Factors influencing transformation rates and formation of products of phenylurea herbicides in soil. J.Agric, Food Chem. 1997.47:3389-3396.