Abstract:In order to improve the targeted accumulation of fungicides on the lesion locations against Fusarium wilt in bananas,polymer nanocarriers(PSI-PHE) were constructed with polysuccinimide(PSI) and phenylalanine(PHE).Then fludioxonil(FLU) was loaded into the nanocarriers to produce PHE-guided nanoparticles(FLU @ PSI-PHE).The infrared spectroscopy,hydrodynamic size,zeta potential,thermogravimetricanalysis and X-ray diffraction analysis were explored to characterize the interaction and loading capacity between nanocarriers and FLU. The results showed that the loading capacity of FLU@ PSI-PHE nanoparticles with 531 nm by hydrodynamic size was up to 45.96% , and the translocation dose of the castor phloem was 1.27 μg/mL,showing cfficient phlocm delivery effect.Compared with low doses of FLU, FLU@ PSI-PHE nanoparticles with the same active ingredient content showed basically equal antifungal activity against Fusarium wilt in bananas. Amino acid-mediated FLU@ PSI-PHE could be efficiently translocated in plant vascular tissues,which provides new technology for targeted treatment of banana Fusarium wilt.