Abstract: This study sought to clarify the residue degradation pattern of forchlorfenuron (CPPU) in kiwifruits and its effects on the mineral elements and storage quality of the fruit. Kiwifruits ‘Miliang No. 1’ were applied with CPPU at concentrations of 5, 10, and 20 mg/L at 25 days after flowering, and CPPU residue levels, 22 mineral elements, and quality indicators were measured during postharvest storage. The results showed that although the degradation rate of CPPU exceeded 98% after 90 days, the residue level in the 20 mg/L treatment group was still higher than the national standard (50 μg/kg) on the day of harvest (68.06 μg/kg) and after 12 days of storage (56.69 μg/kg). CPPU treatment significantly altered mineral element accumulation in kiwifruits, with the control group showing significantly higher P, Ca, Mg, As, Mn, Mo, Sr, Ti, and Sn contents than the treated groups at harvest. During storage, the CPPU-treated groups exhibited a faster decline in hardness, higher total soluble solids content (TSSC), and significantly increased mass loss and rot incidence, with the 20 mg/L group rotting earliest, indicating that CPPU reduces fruit storability. Correlation analysis showed that CPPU treatment weakened the correlations among most elements, but enhanced or reversed those among a few elements. Principal component analysis (PCA) revealed clear separation between the control and treated groups, with the control group associated with elements such as Sn, P, S and a lower softening degree, whereas CPPU treatment accelerated rot and mass loss. Collectively, CPPU treatment interferes with mineral element homeostasis in kiwifruits, accelerates fruit senescence, and poses residue risks when applied at 20 mg/L. It is recommended that the application concentration of CPPU in production be controlled below 10 mg/L.

Key words: kiwifruit; forchlorfenuron; mineral elements; storage performance; pesticide residues; correlation analysis