Variation in egg-induced HR is independent of cell death induced
by other biotic stresses
To understand whether a B. nigra plant showing absence of
egg-induced HR-like cell death was also impaired in the ability to
develop cell death against other biotic stresses, we tested two B.
nigra accessions that either consistently develop a strong HR-like
response (SF48-O1) or no cell death at all (DG1-S1). We treated them
with egg wash and extracts of the Gram-negative hemibiotrophic bacteriumXanthomonas campestris pv. Campestris (Xcc) and the
necrotrophic fungi Alternaria brassicicola and Rhizoctonia
solani . We found that DG1-S1, the accession unable to develop cell
death upon egg wash, could still develop a cell death against pathogen
extracts (Supporting information: Fig. S1). In other words, egg wash
induced different HR-like severity between the two accessions unlike the
three pathogen extracts (Kruskal–Wallis test,p < 0.01) (Fig. 1, Supporting information: Fig. S2).