Smut Control

Symptoms

Look for a long, curved black whip like structure emerging from the top of the cane, covered with a thin silvery membrane that breaks to release black powdery spores. Affected clumps are thin, grassy and stunted with many slender tillers, and the canes are short with narrow leaves.

Damage

Smut, caused by the fungus Sporisorium scitamineum, produces the characteristic black whip and turns plants thin and grassy, drastically cutting cane number, weight and sugar content. The disease spreads through infected setts and airborne spores, and it builds up strongly in successive ratoons. Susceptible varieties can suffer very heavy loss.

Organic & cultural control

Grow resistant varieties and use healthy seed from a disease free plot. Remove and carefully bag and destroy the smut whips early before the spores spread, ideally before the membrane bursts. Avoid taking ratoons from an affected field, follow crop rotation, and treat setts with bio agents like Trichoderma along with healthy seed selection.

Chemical control

Treat setts before planting by dipping in a recommended fungicide solution such as carbendazim or by hot water and fungicide therapy to kill seed borne infection. There is no spray that cures an already whipping plant, so seed treatment and rouging are the key measures. Always read and follow the product label, observe the pre-harvest interval, and consult your KVK or a qualified agronomist before applying.

Always follow the product label, the recommended pre-harvest interval, and your local KVK or agronomist. Pesticide approvals change, so verify before use.

Prevention

Choose resistant varieties and plant healthy, fungicide treated setts from a disease free seed plot. Inspect the crop regularly and remove smut whips by bagging and destroying them before spores spread. Avoid ratooning affected fields, follow crop rotation, and never use seed from a smut affected crop.