Abstract:

Dry rot, caused by Fusarium sulphureum spp., is one of the most important postharvest diseases of potato tubers
in Gansu province. Potato tuber slices (cv. Long Shu No.3) were treated with T-2 toxin at 1 μg/mL. The efficacy of T-2 toxin
treatment on the lesion diameter of potato tuber slices inoculated with F. sulphureum, the activities of key enzymes involved
in phenylpropanoid pathway and metabolites were investigated. The results showed that T-2 toxin treatment significantly
decreased lesion diameter of potato tuber slices inoculated with F. sulphureum, and enhanced the activities of phenylalanine
ammonia-lyase (PAL) and coumaric acid-coenzyme A ligase (4CL), and also improved the accumulation of lignin, total
phenolic compounds, flavonoids and anthocyanin. It is suggested that T-2 toxin treatment at lower concentration induces
resistance against dry rot in harvested potato tubers by activating phenylpropanoid pathway.

Key words: potato, T-2 toxin, induced resistance