Differential Changes in Some Antioxidant Enzymes and Biomolecules in Leaves of Tomato Infected by Phytophthora infestans (Mont.) de Bary

In Cameroon, tomato yields remain low due to attack by pathogens and insects. Phytophtora infestans (PI) is a phytopathogenic fungus responsible for the downy mildew of tomatoes, fungal disease enormous economic losses. To contribute search means control, stimulatory effect defence system extracts some plants was evaluated. Tomato were treated with aqueous macerates Callistemon citrinus (C. citrinus) Cymbopogon citratus citratus) at 10% (W/V). After 4 days spraying macerates, inoculated virulent strain PI. leaves collected 2-day intervals 10 used determine contents chlorophyll a, proteins, carbohydrates, lipids, amino acids proline. The activities main antioxidant enzymes also assessed: Ascorbate Peroxidase (APX), Phenylalanine Ammonia Lyase (PAL), (POX), Superoxide Dismutase (SOD). results showed that treatment C. their inoculation PI induced an increase in protein, carbohydrate, lipid, acid proline leaves; APX, PAL, POX, SOD activities. Our suggested increased metabolite synthesis on one hand, enzymatic activities, other could mitigate oxidative damage occured during pathogen expansion. Aqueous be as natural products stimulate against infestans.