Divisi
Sugarcane mosaic virus
Sugarcane mosaic virus · Viral
Photo: Jeffrey W. Lotz, Florida Department of Agriculture and Consumer Services, Bugwood.org · CC BY 3.0 us
Sugarcane mosaic virus is a plant virus (a potyvirus — a germ far too small to see, that lives inside the plant's sap). It rides into a new field mainly inside infected setts (the seed-cane cuttings you plant), and once growing it is carried plant-to-plant by aphids — small soft sap-sucking insects — in the few seconds it takes one to probe a leaf. There is no spray that cures it; the plant stays infected for life. It also attacks maize and sorghum, so those crops and nearby grasses act as a hidden store of the virus.
Mary Ann Hansen, Virginia Polytechnic Institute and State University, Bugwood.org · CC BY 3.0 us 
Maathavi Kannan, Ismanizan Ismail, and Hamidun Bunawan · CC BY 4.0
Why it matters
Once a stool is infected there is no cure — no spray, no medicine will clean it, and it stays sick for the rest of its life and passes the virus into every ratoon and every sett you cut from it. A bad case can rob you of up to 40% of your cane and sugar on a susceptible variety, especially when plants catch it young. Because it hides inside the plant and travels in your own planting material, by the time you see it across the field the damage is already done — so the whole fight is won or lost before you plant, in the setts and variety you choose.
When to act
No curative treatment; act pre-emptively with virus-free setts and resistant varieties, as the virus is carried in planting material and spread by aphids.
This guidance is general, compiled from published agronomic references including FAO and CABI. Thresholds and timing shift with your crop, your variety and the season.
In much of the region a spray is simply called mushonga — medicine. But a chemical group you cannot name is one you cannot rotate, and a product you did not write down has no pre-harvest interval you can observe. Mushonga, and other farming words →
The full sugarcane mosaic virus field guide
- Identify it
- Scout for it
- Control it
15 field-guide sections in the app
The full guide to sugarcane mosaic virus — every symptom to check, how and when to walk your field looking for it, and the controls that actually work, ranked. Built into your crop plan, so you are told to look before it costs you a harvest.
Crops it affects
Frequently asked questions
How do I identify sugarcane mosaic virus?
The first thing you see: hold a young leaf up to the light and look near the base — you'll see a mosaic, a mix of pale-green, yellow-green and normal dark-green patches, blotches or short stripes running along the leaf, like a shadow-pattern that doesn't belong. It shows clearest on the youngest leaves and fades as the leaf ages.
When should I take action against sugarcane mosaic virus?
No curative treatment; act pre-emptively with virus-free setts and resistant varieties, as the virus is carried in planting material and spread by aphids.
How do I control sugarcane mosaic virus?
Prevent — grow a resistant variety (your strongest tool): plant a mosaic-resistant sugarcane variety wherever you can. This is the single most effective line of defence — a resistant crop shrugs off infection that would cripple a susceptible one.
Which crops does sugarcane mosaic virus affect?
Among the crops covered here: Maize, Sorghum, Sugarcane.
Catch it before it costs you a harvest
Divisi builds scouting into your crop plan — it tells you when to walk your field, what to look for at that stage, and what to do when you find it. Free for farmers, works offline.
Check what grows on your farm