RNA Antiviral for Crops

Agricultural Losses: Plant viruses cause over $30 billion in annual global losses, with pests and diseases destroying nearly 40% of annual crops.

Cucumber Mosaic Virus (CMV): CMV infects over 1,200 plant species, causing significant yield losses (e.g., 25-30% in Indian banana plantations, up to 70% in pumpkin/cucumber/melon crops). Spread by aphids.

RNA Silencing: Plants naturally use RNA silencing (dsRNA triggers DCL enzymes to produce siRNAs, destroying viral RNA) as a defense against viruses.

HIGS vs. SIGS: Host-Induced Gene Silencing (HIGS) involves genetically modifying plants for continuous dsRNA production but faces regulatory and cost hurdles. Spray-Induced Gene Silencing (SIGS) uses RNA sprays, but traditional dsRNA mixes are inefficient.

New “Effective dsRNA” Approach: Researchers developed a new approach that enhanced the effectiveness of RNA silencing against CMV.

Engineered dsRNA: Genetically engineered dsRNA enriched with highly functional siRNA.

Key Advantages: The new approach: (i) precision, directing the plant’s immune system toward the viral particles’ most vulnerable genetic regions, boosting its ability to fight infection. (ii) a stronger defense because the more-effective dsRNA targets multiple regions of the viral genome simultaneously, making it harder for the virus to mutate and escape. (iii) effective dsRNA can be redesigned in about a month to target new viral strains.

Promising Results: Demonstrated up to 80% viral load reduction in lab settings using Nicotiana benthamiana. Effective against multiple CMV strains.

Future Steps: Developing spray-based solutions and field trials are underway to test effectiveness in natural conditions.

Broader Applications: The technology could be adapted for other plant viruses, fungal and bacterial diseases, and insect pests.

Challenges: RNA stability in outdoor conditions (sunlight, rain), cost and scalability of production, and regulatory approvals.