The mechanism of induced resistance against Fusarium dry rot in potato tubers by the T-2 toxin

Potato (Solanum tubersosum L) is the most important non-grain source of human diet for the people living at poverty line. Potato suffers from many notorious biotic stresses, including dry rot caused by Fusarium spp. Treatments of potato tubers with 1 mg L-1 of T-2 toxin produced by Fusarium spp. induced resistance against Fusarium sulphureum by new elicitor-like activity. To investigate the mechanism of induced resistance by T-2 toxin against dry rot of potato, tuber slices were treated with T-2 toxin, followed by the inoculation with F. sulphureum spores. Results in this study showed that the reduction of disease area was linked with higher abundance of reactive oxygen species (ROS) and new phenylpropanoid metabolites. T-2 toxin treatment increased ROS accumulation and induced the activities of enzymes involved in ROS and phenylpropanoid metabolism. At the same time, T-2 toxin treatment also up-regulated proteins involved in ROS and phenylpropanoid metabolism determined by iTRAQ (isobaric tags for relative and absolute quantitation) assay, as well as genes encoding proteins involved ROS and phenylpropanoid metabolism. Taken together, this study provides substantial evidences that T-2 toxin induced resistance related proteins and genes in potato tuber slices to suppress the dry rot severity of F. sulphureum.