StPOPA, encoding an anionic peroxidase in Solanum tuberosum, enhances resistance against Phytophthora infestans

Potato late blight, caused by Phytophthora infestans, is one of the major threats affecting the quality and output of potato all over the world. Reactive oxygen species (ROS) acted as a signal molecule to transmit signals in plants at the early stage of disease infection, and it could induce disease resistance of the plant, including potato late blight. Anionic peroxidases in many plants were reported to be involved in defense to disease. However, limited information about anionic peroxidase genes is available for the potato. Here, we reported that the expression of the StPOPA, a gene encoding a suberization-associated anionic peroxidase, was associated with resistance in potato against P. infestans. The StPOPA gene was induced by P. infestans infection, mechanical damage, jasmonic acid and ethylene treatment. Overexpression of the StPOPA gene in potato enhanced the resistance against P. infestans via promoting the accumulation of callose in the cell wall and ROS in the cytoplasm, which restricted the infection and spreading of the disease possibly by purposeful programmed cell death. Taken together, our results suggested that the StPOPA gene contributed to potato immunity against P. infestans and this gene could be used for the genetic improvement of resistance against potato late blight.