Insights into the molecular basis of biocontrol of Botrytis cinerea by Clonostachys rosea in tomato

Abstract Grey mould (Botrytis cinerea) is a common disease in tomato (Solanum lycopersicum L.), which can cause a severe reduction in production. Clonostachys rosea (C. rosea) is an effective biological control agent that can inhibit the growth and establishment of B. cinerea and significantly improve tomato resistance to B. cinerea. However, the molecular basis of B. cinerea resistance mechanisms induced by C. rosea is still unknown. In this study, integration of proteomic and transcriptomic approaches was used to analyse B. cinerea resistance induced by C. rosea in tomatoes. The results revealed that C. rosea treatment resulted in the overexpression of several genes and proteins associated with oxidation-reduction (REDOX) reactions and defense-related enzymes. In this regard, we recorded greater levels of expression in peroxisome-related enzymes, the ascorbate–glutathione (AsA–GSH) cycle and the phenylpropane pathways. The results showed that the activation of peroxisome-related proteins and proteins associated with the AsA-GSH cycle pathways could enhance B. cinerea resistance in plants by scavenging ROS accumulated due to disease infection and maintaining the ROS balance in cells. In addition, the activation of the enzymes associated with the phenylpropanoid pathway can contribute to enhanced B. cinerea resistance by synthesizing primary and secondary metabolites that can inhibit the establishment of invading pathogens in the host. Overall, the results of this study shed some light on the molecular basis of the mechanism of B. cinerea resistance induced by C. rosea and provided a deeper understanding of detailed regulatory pathways associated with resistance.