Figure 1. Intraspecific variation of HR-like cell death inB. nigra accessions. HR-like cell death induced by egg wash in
nine accessions. Treatments were applied on the abaxial side of the leaf
as drops. Egg-wash induced symptoms were scored in severity: 0, no
visible response; 1, brown spots underneath egg wash-treated spot, only
visible at abaxial side leaf; 2, cell death also visible at adaxial side
of leaf, spot smaller than 2 mm diameter; 3; cell death covering the
size of the egg wash-treated spot; 4, cell death spreading lesion beyond
the treated spot. Controls (MES buffer) did not induce visible symptoms
(not shown). For each treatment/accession combination N=10. Different
letters indicate significant difference between accessions
(Kruskall-Wallis test, p -value < 0.05).