Constitutive expression of Vr-ERE gene in transformed grapevines confers enhanced resistance to eutypine, a toxin from Eutypa lata

Eutypine (4-hydroxy-3-[3-methyl-3-butene-1-ynyl] benzaldehyde) is a toxin produced by Eutypa lata, the causal agent of eutypa dieback of grapevines. Recently, a eutypine detoxifying gene ( Vr-ERE) encoding an NADPH-dependent aldehyde reductase which converts eutypine into the corresponding alcohol, eutypinol, a non-toxic form of the toxin, has been cloned. We report here the obtention of transgenic plants from grapevine rootstock 110 Richter Vitis berlandieri× V. rupestris that express the Vr-ERE gene. The over-expression of Vr-ERE gene in grapevine tissues increases their detoxification capacity. The growth and development of the transgenic plants cultured in vitro exhibiting a high Vr-ERE activity were not affected by the presence of 300 μM of toxin whereas the growth of untransformed control plants was highly inhibited. These results suggest that the Vr-ERE gene is an efficient candidate to confer resistance to the toxin and opens new opportunities to study the role of the toxin in the development of the disease.