Summary
Apoplectic breakdown from Grapevines Trunk Diseases (GTDs) has become a serious challenge to viticulture in consequence to drought stress. We hypothesise that fungal aggressiveness is controlled by a chemical communication between host and colonising fungus.
We introduce the new concept of a “plant surrender signal” accumulating in host plants under stress and triggering aggressive behaviour of the strain Neofusicoccum parvum (Bt-67) causing Botryosphaeriaceae-related dieback in grapevines.
Using a cell-based experimental system (Vitis cells) and bioactivity-guided fractionation, we identify trans-ferulic acid, a monolignol precursor, as “surrender signal”. We show that this signal specifically activates secretion of the fungal phytotoxin Fusicoccin A. We show further that this phytotoxin, mediated by 14-3-3 proteins, activates programmed cell death in Vitis cells.
We arrive at a model pinpointing the chemical communication driving apoplexy in Botryosphaeriaceae-Vitis interaction and define the channelling of phenylpropanoid pathway from the lignin precursor, trans-ferulic acid to the phytoalexin transresveratrol as target for future therapy.
Competing Interest Statement
The authors have declared no competing interest.
