Exploring the Antifungal Potential of Arginine in Controlling Chestnut Rot Disease

Arginine (Arg) can induce plant resistance. However, few know about its direct effect on fungal pathogens.. This study found that arginine could inhibit the growth of the pathogenic fungus Diaporthe nobilis , a major causal agent of rot disease on edible nuts from Castanea trees, with an inhibition rate of at most 66.9%. After chestnuts were treated with Arg, the disease index of rot caused by D. nobilis decreased significantly, dropping from 91.67 to 20.83 at most. Transcriptome analysis showed that at least 225 differentially expressed genes (DEGs) in D. nobilis were inhibited by arginine. Among them, the expression of genes related to pathogenicity, such as transport proteins, secondary metabolites, degrading enzymes, and organic metabolism, was downregulated. These results provide novel insights into the potential antifungal mechanism of arginine and suggest that arginine could be a potential safe alternative for controlling rot diseases of postharvest foods.