Residues and Application Safety Assessment of Difenoconazole on Cucumber and Soil

In order to study the residual characteristic and safety of difenoconazole in cucumber,field experiment and laboratory testing were conducted to reveal residual degradation dynamics and the final residues of difenoconazole in cucumber and soil.The results showed that the half-life of difenoconazole in cucumber and soil were 2.9days to 4.0days and 12.5days to 16.1days,respectively;residue degradation rate in cucumber at 14days after application was above 92%,and it was above 85%in soil at 42days after application.When the cucumber was sprayed 4to 5times with 125.0g / hm 2 and 187.5g / hm 2 of difenoconazole(250g / L EC),the last application was done 2days before harvesting,the residue of difenoconazole in the harvested cucumber was lower than 1mg / kg.It was suggested that the preharvest interval of difenoconazole in cucumber was 2 days.