Differential occurrence of suberized sheaths in canes of grapevines suffering from black dead arm, esca or Eutypa dieback

Pierrette Fleurat-Lessard (1) , Andrée Bourbouloux (2) , Florence Thibault (2) , Eric Ménard , Emile Béré , Christophe Valtaud (2) , Gabriel Roblin (2)

1 SEVE - Sucres & Échanges Végétaux-Environnement [Équipe du laboratoire EBI Poitiers]
2 EBI [Poitiers] - Écologie et biologie des interactions

Compared to healthy canes of Ugni-Blanc grapevines, structural modifications were observed in August in wood of growing canes showing foliar symptoms induced by esca and Eutypa Dieback. The observed changes appeared attenuated in canes of the current season sampled in December. In contrast, Black Dead Arm (BDA) did not induce significant modifications compared to healthy canes. A seasonal pattern in suberization was observed in control canes since a first suberized sheath occurred in mid-July at the interface xylem ring/pith and a second sheath was built up in August till December at the interface primary phloem/cortex. The same pattern was observed in BDA-attacked vines. In contrast, these continuous structural barriers were not formed in July and August in canes of the current season in grapevines attacked by esca or Eutypa dieback, but restored in the canes observed in December. These structural modifications were quantified and these events were discussed in the scope of plant physiology and pathogenicity of the implied fungi.

Mots clés: Black dead arm; esca; Eutypa dieback; Grapevine; Histology; Suberin

Domaines: Biologie végétale

Pierrette Fleurat-Lessard, Andrée Bourbouloux, Florence Thibault, Eric Ménard, Emile Béré, et al.. Differential occurrence of suberized sheaths in canes of grapevines suffering from black dead arm, esca or Eutypa dieback. Trees - Structure and Function, 2013, pp.1-14. ⟨10.1007/s00468-013-0859-z⟩. ⟨hal-00799730⟩