Degradation of four fungicides in tropical soils from Hainan, China

In tropical districts, the production of crops is affected by fungal, bacterial and viral origins. Chlorothalonil, myclobutanil, propiconazole and difenoconazole were the four fungicides which were effective to prevent these diseases. The degradation and residue of four fungicides in tropical soils were investigated in the present study. The results showed that the four fungicides were closely related with the times and dosage of application, and the weather after spraying. The half-lives of the four fungicides in tropical soils were 5.2, 14.9, 15.8 and 13.8 days, respectively. After the third sampling time, the residue of the four fungicides were detected, but they were lower than 1 mg/kg and they were safe to use under the tropical climate.