【作者】 任晓萍；

【导师】 常有宏；

【作者基本信息】 南京农业大学 ， 果树学， 2009， 硕士

【摘要】 桃是一种深受消费者喜爱的水果,也是世界上重要的水果种类之一,我国桃的总产量1994年已跃居世界第一位。生产中为了保证桃的产量和外观品质,不得不使用农药,近年来随着病虫害抗性的增强,农药在桃上的使用量越来越大,桃的质量安全已经成为消费者日益关心的问题。本文通过分析桃常用农药的动态残留规律,探索性提出了桃安全生产控制技术及用药规范,具体结果如下：1.探索出以甲醇作提取溶剂,加少量酸液,调剂提取系统pH偏酸性,提取效果佳,通过调节提取液酸碱度,以二氯甲烷进行反复萃取净化,用反相高效液相色谱(HPLC)进行分析,同时处理检测桃中多菌灵和吡虫啉的方法；用丙酮提取,过弗罗里硅土小柱净化共同处理和用气相色谱(GC)共同检测百菌清和三氟氯氰菊酯的方法,方法平均回收率在81.6%～100.3%之间,检出限低于0.05mg/kg,相对标准偏差(RSD)≤5.14%。标准曲线相关系数0.999以上。两种方法大大的缩短了工作量,并且减少了有机溶剂的使用。2.研究了多菌灵、吡虫啉、百菌清、三氟氯氰菊酯四种农药在桃上的残留规律。结果表明多菌灵稀释1000倍、500倍、250倍的半衰期分别为：4.54d、6.70d、7.53d；吡虫啉降解速度过快,无法求得半衰期；百菌清稀释800倍、400倍、200倍的半衰期分别为：7.63d、9.93d、12.37d；三氟氯氰菊酯稀释2000倍、1000倍、500倍的半衰期分别为：20.43d、11.02d、15.10d。多菌灵采用推荐浓度喷施2次所生产的桃达到安全的标准,增加浓度和增加喷药次数所生产的桃子安全性较差；吡虫啉无论采用推荐浓度还是增加浓度和增加喷药次数,最终残留均不超标；百菌清采用推荐浓度喷施2次和喷施3次均不超标,但加大浓度喷施时均超标.三氟氯氰菊酯无论采用推荐浓度还是加大浓度或增加喷药次数,最终残留均不超标,但高浓度喷施过的果实,其果皮中含有大量的三氟氯氰菊酯。3.对果实不同部位农药残留量的检测结果显示：套袋果实果皮中多菌灵的残留量高于不套袋果实果皮中的残留量；套袋果实果皮中百菌清和三氟氯氰菊酯的残留量低于不套袋果实果皮中的残留量；果肉中农药残留量远远低于果皮中农药残留量；高浓度农药喷施过的果皮果肉中用药残留量均高于低浓度的果皮果肉中的农药残留量。因此,建议水果一定要清洗吃,最好进行削皮,以减少摄入水果中的农药残留。4.从农药的选用方面、用药浓度、用药次数方面、果实套袋、园区处理、安全食用等几个方面,对桃的质量安全控制提出建议：杀菌剂尽量选用百菌清；多菌灵和百菌清应采用推荐浓度喷药,病害严重时可适当增加喷药次数；吡虫啉和三氟氯氰菊酯可在推荐浓度的基础上适当增加浓度；果实进行套袋处理；园区应挖掘排水沟；食用水果时要清洗或削皮食用。更多还原

【Abstract】 Peach is a favorite fruit by consumers. It also is the world’s most important types of fruit. From 1994, China has become the world’s largest peach producer. In order to ensure the quality and appearance of peach, farmers have to use pesticides. In recent years, resistance to pests growing stronger and stronger, farmers must to use more and more Pesticides. So the quality and safety of peach have become questions which are concerned about by consumers. In this paper, through analyzing the pesticide dynamic residues common law in peach, control technology in peach’s safety production and pesticides use norms was investgated. Specific results are as follows:1. The detection method of Carbendazim and Imidacloprid in peach was founded by HPLC. Pre-treatment condition was methanol as extraction solvent (pH<7), dichloromethane as purificant (pH>7). The detection method of Chlorothalonil and Lamba cyhalothrin in peach was founded by GC. Pre-treatment condition was acetone as extraction solvent, florisil soil as purificant. The average recoveries were between 81.6%-100.3%, and the Detection limit of less than 0.05mg/kg, and the RSD≤5.14. Correlation coefficient of standard curve more than 0.999. This series of method greatly reduces the workload and reduced the use of organic solvents.2. Studied the residues law of Carbendazim, Imidacloprid, Chlorothalonil, Lamba cyhalothrin in peach. Results are as follow, the half-life of Carbendazim diluted 1000 times,500 times,250 times are 4.54d、6.70d、7.53d. The degradation rate of Imidacloprid was too fast, so that half-life can not be obtained. The half-life of Chlorothalonil diluted 800 times,400 times,200 times are 7.63d、9.93d、12.37d. The half-life of Lamba cyhalothrin diluted 1000 times,500 times,250 times are 20.43d、11.02d、15.10d. If we use recommended concentration of carbendazim and spray 2 times, the peach production is safe. But if increase concentration and increase the times, the peach production is unsafe. Whether we use recommended of Imidacloprid concentration or increase concentration and increase the times, the final residues are less than MRL. If we use recommended concentration of Chlorothalonil and spray 2 or 3 times, the final residues are less than MRL. But if we increase concentration, the final residues are more than MRL. Whether we use recommended of Lamba cyhalothrin concentration or increase concentration and increase the times, the final residues are less than MRL. But when we use high concentrations, the residue of Lamba cyhalothrin in the peel is high.3. In the laboratory, the peaches were washed and peeled, then pesticides residuce were detected pesticides residues in peel, pulp, and whole peach. From the results we can see, residues of Carbendazim in peel which were bagged are more than those that without been bagged, residues of Chlorothalonil and Lamba cyhalothrin in peel which were bagged are less than those that without been bagged. Pesticides residues in peel which were washed are less than those that without been washed. Pesticides residues in pulp are far less than that in peel. Pesticides residues in peel and in pulp which were sprayed by high concentration pesticides are more than that were sprayed by low concentration. So, we suggest that fruits should be washed or peeled before eat, and then reduce the intake of pesticide residues in fruit.4. Make recommendations on the quality and safety control of peach from how to choice pesticides, which concentrations and times should we use, when to bag, how to deal the garden and how to eat fruits safety. It is better to selected chlorothalonil as fungicide; We should use recommended concentrations of Carbendazim and Chlorothalonil to spray; If disease is serious, we can add medication times; we can spray Imidacloprid and Lamba cyhalothrin use the concentration a little more than recommended; Fruits should be bagged; Drainage should be scooped in garden; Fruits peel should be cut when we eat fruits.更多还原