Fig. 7.

Influence of ABA, SA, and JA signalling pathways on NH₄ ⁺-IR against Pst. Four-week-old tomato mutants impaired in these signalling pathways were grown under control and NH₄ ⁺ treatments and inoculated by dipping in a bacterial suspension of Pst. The disease rating was scored for wild-type tomato plants of Ailsa Craig (Ailsa), Moneymaker (MM), and Castlemart (Cast) and their respective ABA-impaired mutant flacca (A, B), SA-impaired mutant NahG (C, D), and JA-impaired mutant def1 (E, F) at 72 hpi. Data show the average of three independent experiments of a pool of 10 plants per experiment ±SE. Letters indicate statistically significant differences (P<0.05; least-significant difference test).