RNA Interference in Plant Interactions with Pathogenic Microorganisms: A Weapon or a Liability?

The RNA interference machinery is crucial for regulating the activity of both native and foreign genes across all eukaryotes. The core protein families involved in this process are Dicer-like, Argonaute, and RNA-dependent RNA polymerase. However, plants exhibit remarkable diversity within each family and extensively use RNA interference mechanisms in their intricate immune responses. This review examines the role of RNA interference in plant interactions with various pathogens, including viruses, viroids, fungi, oomycetes, and bacteria. Plant diseases cause an estimated $220 billion in annual damage, with microorganisms accounting for approximately $150 billion. Hence, the focus is on the most severe plant diseases, specifically those caused by fungi and viruses. Additionally, recent biotechnological advancements are discussed, with an emphasis on the application of RNA interference for the development of novel plant defence strategies.