Tomato SlPti5 plays a regulative role in the plant immune response against Botrytis cinerea through modulation of ROS system and hormone pathways

Abstract

While SlPti5 has been shown to play a crucial role in the regulation of antagonistic genes in Solanum lycopersicum and Arabidopsis against pathogen infection, there have been no comprehensive studies on the effects of SlPti5 on the regulatory response mechanism of reactive oxygen species (ROS) system and hormone pathways during growth and disease resistance of tomato plants. Here, we investigated the function of SlPti5 in the defense response of tomato against Botrytis cinerea utilizing a virus-induced gene silencing (VIGS)-based system. Expression profile analysis showed that SlPti5 was significantly induced upon B. cinerea infection, with high expression levels in the leaves and fruit of tomato. VIGS-based silencing of SlPti5 inhibited early vegetative growth, increased the plant's susceptibility to infection, promoted the development of ROS, affected the expression of genes involved in the ROS scavenging system, and attenuated the expression of genes associated with pathogenesis and the ethylene/jasmonic acid signaling pathways. In sum, our data demonstrated that SlPti5 stimulates the immune response of tomato plant to Botrytis cinerea infection by involving the ethylene (ET)- and jasmonic acid (JA)-mediated pathways and modulating the expression of some key pathogenesis-related (PR) genes.