Induction of phenylpropanoid metabolic activity in muskmelon fruit by postharvest BTH treatment and challenge inoculation with Trichothecium roseum

Muskmelon fruit (Cucumis melo L.cv.Yujinxiang) was dipped at 0.1g/L of BTH for 10min.The efficacy of BTH dipping treatment and challenge inoculation with Trichothecium roseum on the activities of key enzyme of phenylpropanoid pathway and metabolites were investigated.The results showed that BTH treatment significantly decreased lesion diameter of muskmelon fruit inoculated with T.roseum.BTH treatment also enhanced the activities of phenylalanine ammonia-lyase (PAL) and Coumaric acid-coenzyme A ligase (4CL) , and increased the contents of total phenolic compounds, flavonoids and lignin.Moreover, challenge inoculation the BTH-induced fruit with T.roseum significantly increased the activities of key enzyme and contents of metobolites in phenylpropanoid pathway.In a conclusion, postharvest BTH treatment increased disease resistance in harvested muskmelon fruit by activating phenylpropanoid pathway.