Response to an ozone gradient of growth and enzymes implicated in tolerance to oxidative stress in Acer saccharum (Marsh.) seedlings Catherine Gaucher, Nadine Costanzo, Paul Widden, Jean Pierre Renaud, Pierre Dizengremel, Yves Mauffette and Normand ChevrierAnn. For. Sci., 63 4 (2006) 387-397DOI: https://doi.org/10.1051/forest:2006019