Abstract:

Nang klangwan and Tainong mango fruits were used as the experimental subjects to conduct BTH treatments. The effect of BTH treatment on the activities of major defense enzymes such as phenylalanine ammonia-lyase (PAL), polyphenoloxiase (PPO) and peroxidase (POD) in postharvest fruits was evaluated to explore the disease-resistance mechanisms of mango fruits from different varieties. Results indicated that the activities of PAL, PPO and POD in Tainong mango fruits were obvious higher than those in Nang klangwan mango fruits during storage. However, after treated with BTH, the Mango fruits from both varieties exhibited an obvious increase in the activities of three enzymes. Meanwhile, more increase in the activities of three enzymes was observed in Tainong mango fruits. In addition, there was an obvious correlation between BTH-induced enhancement of disease resistance and the activities of PAL, PPO and POD in fruits.

Key words: mango, BTH, defense enzyme