Amelioration of chilling stress by arginine in tomato fruit: Changes in endogenous arginine catabolism

Freshly harvested tomato fruit were pretreated with 0.2 mM arginine at −35 kPa for 0.5 min and then stored at 2 °C for 28 d to investigate the effect of exogenous arginine treatment on endogenous arginine catabolism in relation to chilling injury (CI). Arginine treatment reduced the CI index of fruit and enhanced accumulation of polyamines, especially putrescine, and proline, which resulted from the increased activities of the catabolic enzymes arginase, arginine decarboxylase, ornithine decarboxylase and ornithine δ-aminotransferase at most sampling times. Nitric oxide synthase activity was also increased by arginine treatment, which at least partly contributed to the increased nitric oxide concentration. These results revealed that the reduction in CI by exogenous arginine may be due to the accumulation of putrescine, proline and nitric oxide induced by activating the different pathways of endogenous arginine catabolism.

► Arginine treatment alleviated postharvest chilling injury in tomato fruit.
► Exogenous arginine regulated enzymes related to endogenous arginine catabolism.
► The levels of putrescine, proline and NO in fruit were enhanced by arginine treatment.
► Arginine alleviated chilling in fruit due in part to activated arginine catabolism.