2.5 Warming induced disease resistance is SA dependent
To examine the potential involvement of SA in warming- mediated resistance against Bc , we conducted pathogenesis assays in an SA deficient transgenic line. Root zone warming was applied for 48h followed by a 3 day recovery period. Following Bc inoculation, disease severity was assessed for 5 days. Figure 9 shows that the warming treatment did not protect the SA deficient NahGtransgenic plants (Brading et al., 2000) from Bc induced disease, indicating that the SA signaling pathway is required for induction of warming mediated resistance against Bc . Bc disease levels in the mock NahG plants were decreased as expected (Ciardi et al., 2000; O’Donnell et al., 2001, 2003) (Figure 8). Similar results were achieved in SA deficient NahG transgenic plants withO. neolycopersici (Supplemental Figure S4 ).