Gene silencing in broomrapes and other parasitic plants of the Orobanchaceae family: mechanisms, considerations, and future directions

Abstract Holoparasites of the Orobanchaceae family are devastating pests causing severe damage to many crop species and are nearly impossible to control with conventional methods. During past decades RNA interference (RNAi) has been seen as a promising approach to control various crop pests. The exchange of small RNAs (sRNAs) between crops and parasitic plants has been documented indicating a potential for the development of methods to protect them via the delivery of the sRNAs to parasites, called host-induced gene silencing (HIGS). Here we describe various approaches used for gene silencing in plants and suggest solutions to improve the long-distance movement of the silencing triggers to elevate the HIGS efficiency in parasitic plants. We also investigate the important biological processes during parasites life cycle with a focus on broomrape species, providing several appropriate target genes that can be used in, especially, multiplex gene silencing experiments. We also touch on how the application of nanoparticles can improve the stability and delivery of the silencing triggers, highlighting its potential for parasitic plants control. Finally, suggestions for further research and possible directions for RNAi in parasitic plants are provided.