Differential regulation of calmodulin, phenylalanine ammonia-lyase, and salicylic acid in response to Botrytis cinerea infection in tomato with different Ca2+ concentrations

To investigate the responses to Botrytis cinerea (B. cinerea) infection and the effects of exogenous Ca2+ on calmodulin (CaM), phenylalanine ammonia-lyase (PAL), and salicylic acid (SA) biosynthesis and concentrations, we investigated the role of exogenous calcium in defense and resistance to the necrotrophic fungus B. cinerea in tomato (Lycopersicon esculentum Mill.). Specifically, 7.5mM Ca2+ was the best treatment for plant resistance, resulting in stable and permanent resistance to the pathogen. This treatment improved plant resistance and the results also confirmed that the concentrations of CaM and SA are negatively correlated with the resistance response.