虫酰肼的稳定性和在水稻及环境中的消解、残留研究

发布时间：2018-03-11 05:37

  本文选题：水稻　切入点：虫酰肼　出处：《湖南农业大学》2015年硕士论文　论文类型：学位论文

【摘要】：本文研究了稻米、稻田水、土等样品中虫酰肼的残留检测方法；虫酰肼制剂、标样及其在稻米基质中的稳定性；虫酰肼在三个省水稻及稻田环境中的消解动态和残留规律,为虫酰肼在水稻上的合理使用提供科学依据。主要结论如下：(1)建立了稻米、稻田水、土壤等样品中虫酰肼残留量的高效液相色谱检测方法。稻米、稻田水样、稻田土壤、水稻植株(稻草)和稻壳中虫酰肼的最低检出浓度均为0.02 mg/kg(mg/L);分析样品中虫酰肼平均添加回收率为86.74%-108.00%；变异系数为0.41%-4.42%。该分析方法可用于我国农产品质量监测部门和环境监测部门对稻米、稻田水、土等样品中虫酰肼的残留量检测。(2)4种剂型虫酰肼商品农药启封后,虫酰肼的含量会随存放时间的延长而降低。其稳定性大致表现为20%虫酰肼悬浮剂34%甲维·虫酰肼可湿性粉剂25%甲维·虫酰肼悬浮剂10.5%甲维·虫酰肼乳油。建议常温存放的4种虫酰肼农药制剂在半年之内用完；浓度为0.1mg/L、10 mg/L和100 mg/L的虫酰肼标准溶液放在常温和冷藏(4℃)条件下贮存,随着贮存时间的延长,3种浓度虫酰肼标准溶液中的虫酰肼浓度均会降低,冷藏(4℃)条件下标准溶液的稳定性比常温条件下好,虫酰肼高浓度标准溶液的稳定性比低浓度标准溶液好。建议常温下使用低浓度虫酰肼标准溶液不要超过3 d,100 mg/L的虫酰肼标准溶液低温(4℃)冷贮时间不要超过1年；虫酰肼添加浓度为0.2 mg/kg和2 mg/kg的稻米样品放在常温、冷藏(4℃)、冷冻(-20℃)条件下贮存,稻米样品中虫酰肼的残留量随贮存温度的升高而降低,随贮存时间的延长而降低。因此,作为食粮的大米,于常温条件下贮存并适当延长贮存期,有利于大米中虫酰肼残留量的减少。但作为科研样品的稻谷和大米,建议冷冻(-20℃)条件下的贮存时间不要超过2个月。(3)采用模拟试验方法,2012和2013年研究了虫酰肼在三个省稻田水、稻田土壤和水稻植株上的消解动态,结果表明,虫酰肼在稻田水、土壤和水稻植株上的消解符合一级化学反应动力学方程：Ct=C0e-kt。虫酰肼在稻田水、土壤和水稻植株中的消解半衰期分别为1.67-6.28 d、4.50-12.60 d和3.16-7.70 d。实验结果表明,虫酰肼属于比较容易降解的农药。(4)20%虫酰肼悬浮剂在水稻上的残留试验结果表明：在三个省的自然条件下,按照推荐的施药量和施药方法在水稻上施用20%虫酰肼悬浮剂,最后一次施药后14天以上收获的稻米中虫酰肼的最高残留量为0.0219 mg/kg,低于我国规定的稻米中虫酰肼最大允许残留限量值(MRL值:2mg/kg)。(5)根据本文试验研究结果,建议20%虫酰肼悬浮剂在水稻上合理使用技术标准为：水稻生长期,用20%虫酰肼悬浮剂150 g/hm2(有效成分虫酰肼30g/hm2)兑水750 L/hm2喷雾施药防治病虫害,最多施药2次(施药间隔7天以上),安全间隔期为14天。
[Abstract]:In this paper, the methods for the determination of fenprohydrazide residues in rice, rice field water and soil, the preparation, standard sample and stability in rice substrates of rice, the dynamics and residues of fenprohydrazide in the environment of rice and paddy fields in three provinces were studied. The main conclusions are as follows: (1) A high performance liquid chromatography (HPLC) method for the determination of fenproyl hydrazide residues in rice, paddy water, soil and other samples was established. The lowest detectable concentration of buproyl hydrazide in rice plant (rice straw) and rice husk is 0.02 mg / kg g / L, the average recovery rate of hydrazide in the analysis sample is 86.74 -108.00 and the coefficient of variation is 0.41-4.42. The method can be used in the quality monitoring department and ring of agricultural products in China. The Department of Environmental Monitoring on Rice, Determination of Tetrahydrazide residues in Paddy Water, soil and other samples. The content of fenproyl hydrazide will decrease with the prolonging of storage time. The stability of 20% butazide suspension agent 34% methyl-hydrazide wettable powder 25% methylethyl hydrazide suspension agent 10.5% methyl retinoic hydrazide emulsifiable oil is suggested. The four insecticide formulations stored at high temperature were used up within half a year. When the standard solution containing 0.1 mg / L ~ (10 mg/L) and 100 mg/L was stored at room temperature and 4 鈩，

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