Residue of 14C - Paclobutrazol in mango

Abstract

Paclobutrazol (PBZ) is a growth regulator used to control vegetative growth, stimulating the reproductive capacity of plants. The PBZ remains active in soil for a long time and its half-life varies with soil type and climatic conditions, which may severely affect the development of subsequent crops. Therefore, this study aimed to evaluate the residues and metabolites of 14 C-PBZ in pulp and peel mango Tommy Atkins. The tests were carried out with mangoes grown in pots of stainless steel and the application of 14 C-PBZ was held in the soil in the canopy projection. To evaluate the level of waste 14 C-PBZ held burning 200 mg of pulp and the organic oxidizer 14 CO 2 evolution was detected by liquid scintillation spectrophotometer. The results of PBZ residues for pulp and peel were 1.65 and 0.37% after two years of application and 4.30 and 1.32% after one year of application, respectively. Analysis of the residue of 14 C-PBZ and its metabolites by high performance liquid chromatography (HPLC) coupled to a photodiode array detector and was not detected the presence of metabolites of the PBZ samples analyzed sleeves.