Long Non-Coding RNA StlincPRI Enhances Resistance to Phytophthora infestans by Regulating Reactive Oxygen Species Homeostasis

Potato (Solanum tuberosum) is the fourth-largest food crop worldwide. However, late blight, caused by oomycete Phytophthora infestans, poses a major threat to global production. Although long non-coding RNAs (lncRNAs) have emerged as key regulators of plant immune responses, their role in potato immune response remains largely unknown. Here, transcriptome profiling of resistant cultivar Qingshu No. 9 and susceptible cultivar Désirée identified a P. infestans-responsive long intergenic non-coding RNA (lincRNA), named StlincPRI, which is significantly upregulated upon infection. Overexpression of StlincPRI activates the expression of pathogenesis-related genes, inhibits pathogen growth, and decreases lesion area upon P. infestans challenge. Moreover, StlincPRI triggers a rapid reactive oxygen species (ROS) burst during the early stage of infection. Subsequently, it alleviates oxidative damage via enhancement of both enzymatic and non-enzymatic ROS scavenging systems to maintain cellular ROS homeostasis. Conversely, silencing StlincPRI results in opposite effects, demonstrating that StlincPRI functions as a positive regulator of potato immunity against P. infestans. These findings provide insights for developing strategies to enhance late blight resistance and hold potential for advancing sustainable potato production.