【作者】 陈齐斌；

【导师】 季玉玲；

【作者基本信息】 南京农业大学 ， 农药学， 2000， 硕士

【摘要】 戊唑醇（Tebuconazole）是德国拜耳公司推出的新一代三唑类高效杀菌剂，对小麦上多种病害有效。为评价该农药在小麦上使用的安全性，并为制定安全使用准则提供参考依据和预测/评价它对地下水影响情况，本课题进行该杀菌剂在小麦中的残留动态规律研究，以及在土壤环境中的迁移分布情况研究。论文主要报道该杀菌剂在以下四个方面的研究结果：第一，戊唑醇在小麦、植株、土壤、水中的残留分析方法；第二，戊唑醇三种剂型——25％水乳剂（EW）（喷雾用）、2％干拌种剂（DS）（种子处理剂）、2％种衣剂（种子处理剂）——和相应施用方式在小麦田间使用后的残留动态；第三，室内戊唑醇土壤薄板层析行为研究，预测戊唑醇在环境土壤中的移动性强弱，包括移动性与土壤理化性状（PH、有机质、土壤质地）的关系，不同环境土壤中迁移性是否存在差异；第四，土柱模拟降雨，淋溶之后戊唑醇在土壤中的纵向迁移分布情况和60cm深处淋出水农药残留，确定农药制剂对地下水的影响情况，分析受雨水淋溶作用迁移分布与农药剂型和土壤质地间的关系。 本试验用气相色谱法电子捕获检测器（GC—ECD）测定农药残留量。 色谱条件：2％OV—1 Chromosorb．w．AW．DMCS（60—80目）1.1m×0.3mm（id）玻璃色谱柱，汽化及检测温度310℃、柱温240℃、载气（N₂）30ml/min。C-R3A数据处理机，纸速1mm/min，外标法定性定量。最低检测量为4.79×10^-12g，方法最低检测浓度为9.57×10^-5～9.6×10^-4mg/kg，添加最小检测浓度0.02mg/kg。以0.02、0.20、2.00mg/kg三个浓度进行进行空白样添加试验，在小麦植株回收率为83.7～93.0％，变异系数为3.72～5.80％；在小麦种子/籽粒中回收率为88.7～92.0％，变异系数为4.72～9.40％；在土壤中回收率为86.6～94.9％，变异系数为5.55～12.24％；在水中回收率为99.7～101.0％，变异系数为1.27～3.43％。 农药残留动态研究结果表明：戊唑醇在小麦中降解，半衰期为5.73—14.97天，降解与施药剂型，施药方式，施药时期/季节等因素有关。降解（半衰期）土壤中水乳剂喷施（5.87天）比干拌种粉剂土壤处理（45.16天）快。种子处理动态研究结果还表明得到的半衰期结果还与残留表达形式有关。生物稀释明显时，农药消解半衰期比残留浓度半衰期长。 25％戊唑醇水乳剂叶面喷施在小麦植株和土壤中的半衰期分别为5.73天和5.87天，降解符合一级动力学方程，残留量与施药恤卜毕业论义 搁公2量和施药次数有关，以推荐有效剂量门 6石7《5刀og al／亩)兑水100kg)施药，间隔期为 20天，施药次数！次．对收获小麦较安全． 种子处理是以戊哗醇0．2～0．4g aU okg种子／亩进行处理并播种，在相同有效成分m．Zg al门)种子处理下，2％戊哗醇种衣剂残留期是2％戊哗醇干拌种粉剂的一倍多，说明残留降解与农药剂型有关，种衣剂持效期比十拌种剂长。两种种子处理剂在小麦中降解也符合一级动力学方程。试验结果以三种形式表示——残留总量和残留相对量（鲜样残留浓度与净样残留浓度），结果显示戊呻醇在小麦中相对于样品的残留浓度变化速率比绝对总量消解速率快的多，2％戊哗醇干拌种粉剂在小麦植株中的残留总量半衰期为6刀2－－m石2天，干样中残留浓度半衰期为5二3—5．90天，鲜样中残留浓度半衰期为3石4＋．79大；二％戊哗醇种衣剂在小麦植株中的残留总量半衰期为 14．97天，干样中残留浓度半衰期为 9．54天，鲜样中残留浓度半衰期为7天。这是出于小麦种子生长发育快产生显著生物稀释作用所致。不过两种不同剂型的种于处理剂在小麦播种后70天在小麦中都无检出，它们对收获小麦较为安全。 2％戊晔醇干拌种粉剂与土壤相拌后进行的残留动态显示，它在土壤中具有较长的残留期，半衰期为45＊天。这与25％戊吟醇水乳剂叶面喷施在士壤中半衰期5．87天差异显著。其原因在于施药季节不同，剂型不同，施药方式（前者为表土下，后者为土壤表面），从而造成戊哗醇有效成分遭受温、光、热、气流及微生物等因素作用强度或程度等方面存在差距；不过由于种子处理每亩施药量极低，且小麦生长期长，受耕作，生物、物理、化学等因素作用，戊哩醇种子处理后播种未造成对土壤环境的污染。 土壤环境中的迁移行为研究表明戊吧醇在土壤中属移动性很弱的农药品种，对地下水潜在危险性极小。且迁移性与土壤特性 0H、有机质、土壤质地)关系不大，淋溶后戊哇醇仅迁移分布于0～10cm的耕作层，且主要分布于0～scm范围的表土层，农药迁移尽管在剂型和土壤环境综合作用下存在差异，但也只限于0～10cm范围，在60cm以下的淋出水中未检出有戊哗醇残留。就试验结果预测，它对地下水是安全的。 本文除得出了不同剂型及相应施药方式下戊晔醇残留动态方程及相关系数，土壤中农药迁移分布情况外。本文还对试验中出现的现象进行了解释，对试验的不足进行了剖析、展望与设想。更多还原

【Abstract】 Tebuconazole is a new type of high performance,low toxicity,broad-spectrum triazole fungicide exploited and produced by Bayer Co.ofGermany. It is effective in the control of many kinds of disease in wheat.In order to evaluate it’s safety and lay down the criterion for using safely,at the same time forecast the degree how much it affect the groundwater,the method of tebuconazole residue determination, degradation behaviorin wheat and soil, as well as movement and leaching in soil was studiedand discussed in this dissertation.Residue was detected by GC with ECD detector. The methodprinciple of sample pretreatmeni and the condition of detection wasbelow:Pretreatment of sample: after extracted twice with acetone, add3%NaCL solution and solveni extract twice with petroleum ether(Keepthe proportion of volume among acetone,3%Nacl and for 2:l:l). If thesample is water, add Nacl and a little of acetone first, then solvent extractwith petroleum ether. The water and water-soluble impurities in extractswas removed by Liquid-Liquid partitioning method. The phase lyingabove of extraction was cleanup with acid-washed active charcoal andanhydrous sodium sulfate before concentrated to be ready for detectionGC chromatographic condition. Column: 0.3mm(id)X l.1m glasscolumn; Stationary phase:2%OV---l;Support: Chromosorb. W. AM.DMCS(60--80); Temperature: Detector, 3l0 C, Injector, 3l0 C,0ven: 240aC. Carrier gas: N2 30ml/min. External standard method toqualify and quantify. Minimal determination quantity (MDQ) was 4.79 Xl0-"g. Minimal determination concentration(MDC) of tebucolazole inwheat,seed, soil and water was 3.2 X l0-’mg/kg, 4.8 X l0-’mg/kg, 9.6 Xl 0"mg/kg, 9.56 X l0-’mg/kg respectively.StUdies on residue of tebuconazole showed:Spraying 25%EW oftebucolazole, the dynamic of pesticide accordedwith C=C,e-*, in wheat as well as in soil. The half lives was 5.73days and 5.87 days, respectively. The finally residue was related to theamount and the times that tebuconazoIe had been sprayed, the moreamount or the more times sprayed, the more the residue was. That’s to say,there was positive relation between residue and amount as well as timessprayed for.Seed treatment was carried out at the dosage of 0.2--0.4g aitebuconazole/l0kg seed/mu, and sowed. Except for difference offormulation, under the same treatment condition(0.2g ai/l0kgseed/mu),degradation between 2%DS and 2%seed coating fOrmulationwas different though both of them accorded with c==C,e-,, too. Thismeant that the degradation of tebuconazole was related to pesticideformulation.On expression of degradation in the research of seed treatmentfOrmulation, the result of residue was represented with three differentpatterns: the total(absolIJte)residue account in wheat,and two types ofrelating residue----concentration related to dry sample and concentrationrelated to fresh sample. There showed that for all tre8tment the changingrate of concentration,especially in fresh sample, was more quick than thatof the total residue account. That’s due to the dilotion of seed groWth.Half lives of 2%DS ranged from 6.02 to 6.62 days fOr the total residueaccount. 5.23 to 5.90 days for concentration in dry sample. 3.64 to 3.79days for fresh samPle. In colltrast, the half lives of 2% seed coatingformulation of tebuconazole,accordingly, was 14.97, 9.54, and 7 days,respectively .however,70 days late when the treated seed had been sowed,residue of tebuconazole wasn’t been detected yet neither in the wheattreated with 2%DS nor in the Wheat treated with 2% seed coatingformulation. So they are all safe to the harvesting wheat also.When treat soil by fixing 2%DS. the dynamic of pesticide residueshowed that the half lives of it was 45. l6 days in soil, which was slowerthan that of 25%EW (spraying,5.87 days half lives was)to degradeReason was that there was difference from season, pesticide formulation,mode of using, and position(th更多还原