SIGS vs. HIGS: opportunities and challenges of RNAi pest and pathogen control strategies

• Published in: Canadian journal of plant pathology 2024-11, Vol.46 (6), p.675-689
• Main Authors: Beernink, Bliss M., Amanat, Nazanin, Li, Vivian H., Manchur, Christopher L., Whyard, Steve, Belmonte, Mark F.
• Format: Article
• Language: English
• Subjects: ARNi; Biological activity; Chemical pest control; Climate change; Crop management; crop protection; Crops; Double-stranded RNA; Economic impact; Environmental impact; Environmental management; Food contamination; Food production; Food security; Food selection; fungal management; Fungi; Gene silencing; gestion des champignons; gestion des ravageurs; HIGS; Homology; Impact resistance; Insecticide resistance; Insects; Mechanical properties; mRNA; Nucleotide sequence; Pathogens; Pest control; pest management; Pest resistance; Pesticides; Pests; Populations; protection des cultures; Ribonucleic acid; RNA; RNA-mediated interference; RNAi; SIGS
• ISSN: 0706-0661; 1715-2992
• DOI: 10.1080/07060661.2024.2392610

Insect pests and fungal pathogens are estimated to cause 20-40% yield reduction to crops annually, causing $290 billion of economic loss every season worldwide. Pest and pathogen impacts are a persistent and ever-increasing problem for global food production, especially due to climate change and growing populations. Frequent use of chemical pesticides has resulted in increased resistance among pests and pathogens due to the strong selection pressure that the pesticides exert, resulting in the rapid accumulation of mutations that confer behavioural, mechanical and/or biochemical resistance within the pest populations. Due to rising resistance and increasing interest in control measures with low environmental impact, there is an immediate need to find alternative pest and pathogen management strategies. RNA interference (RNAi) has been developed as a control strategy by exploiting inherent cellular defence processes, providing a species-specific biological approach to crop management. Delivery of double-stranded RNA (dsRNA) can be accomplished non-transgenically by spray-induced gene silencing (SIGS), virus-mediated host-induced gene silencing (VmHIGS) or transgenically through host-induced gene silencing (HIGS), specifically targeting pest and pathogen messenger RNAs with sequence homology. Accomplishing effective RNAi strategies requires consideration into how SIGS, VmHIGS, and HIGS approaches intersect with the crop species and pest or pathogen being targeted. Additional technical advancements for the delivery and uptake of dsRNAs, messenger RNA target identification and the possibility of insect or fungal dsRNA resistance are currently being explored. These considerations will enhance the utility, ease of use and implementation of both spray-based and transgenic applications of RNAi technology for improved food security.