“…3 can occur, at least transiently, in other conditions that involve oxidative stress (Vanacker et al, 2000;Bick et al, 2001;Gomez et al, 2004a). Such changes in glutathione seem to be of functional importance in linking intracellular H 2 O 2 to pathogenesis-related (PR) responses (Han et al, 2013a,b), and several other studies point to an important role of glutathione in determining plant responses to biotic stress (Ball et al, 2004;Parisy et al, 2007;Schlaeppi et al, 2008;Baldacci-Cresp et al, 2012). The mechanisms by which glutathione is involved in oxidative stress signalling remain to be elucidated but may involve processes such as formation of protein disulfides, S-glutathionylation, or S-nitrosylation (Dixon et al, 2005;Feechan et al, 2005;Tada et al, 2008;Palmieri et al, 2010;Zaffagnini et al, 2012).…”