Monitoring of Defense Enzymes (Phenylalanine Ammonia Lyase and Peroxidase) in Magnaporthe oryzae Infected Leaves after Treatment with Green Synthesized Silver Nanoparticles

Objectives: In this study, we focus on the amount of the two defence enzymes phenylalanine ammonia-lyase (PAL) and peroxidase (POX) expressed with regard to the treatment of green synthesized silver nanoparticles. Materials and Methods: The leaf blades were infected with Fungal spores and silver nanoparticles by spraying, and following infection, we estimated the enzyme activity of PAL and POX. The PAL activity is considered by using cinnamic acid as a standard. Results: Our results showed both the PAL and POX enzymes were found to be elevated on infection with spores, and on treatment, the activity was reduced in both cases. There was a significant elevation of PAL (8.937±0.55) in infected leaves, which could be due to infection and on treatment, the enzyme activity was reduced which possibly could be because of the antifungal activity of the synthesised nanoparticles. The POX levels exceeded the control by 417.86%, 807.14% and 921.43% respectively for infected, treatment with AgNPs and treatment with positive control. This confirms the role of the peroxide enzyme in disease control and resistance. Conclusion: This enzyme activity study to our knowledge is the first report done on the infected rice plants with Magnaporthe oryzae and on treatment with silver nanoparticles. This could pave the way to understanding the role of these enzymes in defence activity.