Effects of fudioxonil on Botrytis cinerea and on grapevine defence response

Anne-Noëlle PETIT, Nathalie VAILLANT-GAVEAU, Anne-Sophie WALKER, Pierre LEROUX, Fabienne BAILLIEUL, Marie-Laure PANON, Christophe CLÉMENT, Florence FONTAINE

Abstract


Botrytis bunch rot of grapes is mainly controlled by applying fungicides at three crop stages: the end of flowering (BBCH 68), bunch closure (BBCH 77) and the beginning of veraison (BBCH 81). The phenylpyrroles derivative fudioxonil is among the most effective fungicides registered to control Botrytis cinerea. Its effectiveness was investigated in relation to spray timing, fungicide resistance and defence responses of grapevine. Frequencies of B. cinerea strains which were resistant to fungicides were evaluated at harvest. The frequencies of resistant phenotypes were similar in all treatments except for a class of multidrug resistant strains (MDR 1) whose frequency increased after fudioxonil applications. None of the treatments tested induced defence responses in flowers/berries after fungicide application, suggesting that fudioxonil effectiveness was not related to a stimulation of plant defence processes. The standard program of three fungicide applications provided the best control of B. cinerea  in the Champagne region in comparison with a single treatment of fudioxonil at any of the crop stages tested.


Keywords


defense responses; fludioxonil; fungicide resistance; grapevine; grey mould; 36 treatment efficacy

Full Text:

PDF


DOI: http://dx.doi.org/10.14601/Phytopathol_Mediterr-9049



Creative Commons License

This work is licensed under a Creative Commons Attribution 4.0 International License (CC-BY- 4.0)

 
Firenze University Press
Via Cittadella, 7 - 50144 Firenze
Tel. (0039) 055 2757700 Fax (0039) 055 2757712
E-mail: info@fupress.com