Cucumber Mosaic Virus (CMV): Wide Host Range, No Cure

Cucumber mosaic virus (CMV) infects a vast number of woody and herbaceous species. Composed of RNA in a protein coat, it hijacks plant cells to replicate, disrupting normal function. CMV multiplies only in living cells and dies quickly outside them.

Transmission Routes

• Mechanical: workers' hands, tools
• Aphid feeding (non-persistent)
• Dodder (parasitic plant)
• Grafting

Vegetative propagation perpetuates CMV. Cuttings from infected plants carry the virus even if asymptomatic. Virus particles exist in all tissues except meristem tips.

Symptoms (Variable by Host & Environment)

• Stunting
• Mosaic: light/dark green or yellow/green patterns
• Leaf/growing point malformation
• Yellow streaking (especially monocots)
• Yellow spotting
• Ring spots or line patterns on leaves/fruit
• Flower color breaking
• Distinct vein yellowing

Many symptoms mimic heat stress, insect damage, PGRs, herbicides, nutrient imbalances. Diagnosis requires lab testing—not visual ID alone.

Management: Exclusion & Vector Control

No chemicals cure or prevent CMV infection.

• Purchase virus-free plants
• Strict aphid control
• Remove all weeds (harbor CMV + aphids)
• Isolate symptomatic plants immediately; obtain diagnosis
• Discard infected plants
• Disinfest propagation tools frequently
• Propagate by seed when possible (avoids vegetative transmission)