Effect of the Sun on Decline Curves and Residue Levels of Azadirachtin in Cucumber under Field Conditions
In this work, an HPLC-based method was developed to determine azadirachtin residues on cucumber.The decline curves of azadirachtin residues in cucumber corresponded with first-order kinetics.The half-lives of azadirachtin in cucumber peel, flesh, and whole cucumber under field conditions at four different orientations of exposure to the sun were 19.42 h to 37.87 h,16.40 h to 47.53 h, and 20.53 h to 39.55 h, respectively, whereas those corresponding values for those unexposed to the sun were 38.12 h to 40.36 h, 60 h to 63.40 h, and 54.22 h to 57.61 h.Terminal residues below the maximum residue limit (mg/kg) were achieved after 3 days of application at either once (750 g a.i./ha) or twice (1500 g a.i./ha) the recommended dosage.Most residues were found on the peel.Hence, removing the cucumber peel before consumption was advisable.Temperature was identified as the key factor affecting azadirachtin degradation in cucumber.
azadirachtin cucumber temperature residue,sun
Yue Zhang Jingzheng You Peiwen Zhang deqiang Qin Dongmei Cheng Zhixiang Zhang
South China Agricultural University, Key Laboratory of Natural Pesticide & Chemical Biology,Ministry South China Agricultural University, Key Laboratory of Natural Pesticide & Chemical Biology,Ministry South China Agricultural University, Key Laboratory of Natural Pesticide & Chemical Biology,Ministry
国内会议
南宁
英文
67-78
2016-11-04（万方平台首次上网日期，不代表论文的发表时间）