Sodium alginate potentiates antioxidant defense and PR proteins against early blight disease caused by Alternaria solani in Solanum lycopersicum Linn.
Fig 5
Histochemical analysis of H2O2 production.
H2O2 production around the site of cell death in tomato leaves was assessed using DAB staining. Compared with the untreated control leaves, sodium alginate-pretreated leaves infected with A. solani showed a time-dependent increase in H2O2 accumulation, evident as a reddish-brown stain formed by the reaction of DAB with H2O2. A1–A5: Untreated control leaves; B1–B5: Untreated S. lycopersicum leaves inoculated with A. solani; C1–C5: S. lycopersicum leaves pretreated with 0.2% sodium alginate; D1–D5: S. lycopersicum leaves pretreated with 0.2% sodium alginate and inoculated with A. solani; E1–E5: S. lycopersicum leaves pretreated with 0.4% sodium alginate; F1–F5: S. lycopersicum leaves pretreated with 0.4% sodium alginate and inoculated with A. solani; G1–G5: S. lycopersicum leaves pretreated with 0.6% sodium alginate; H1–H5: S. lycopersicum leaves pretreated with 0.6% sodium alginate and inoculated with A. solani.