Red rot of sugarcane disease by jagmohan sir

 RED ROT OF SUGARCANE:This is one of the most severe of the known diseases of sugarcane.

Causal Organism: Colletotrichum falcatum

Symptom: The 3rd and 4th leaves (from the top) of the infected plants display yellowing and drying. At a later stage, show discoloured lesion on the rind. Fungal spores develop on rind and nodes.

3. If the diseased stalk split open, reddened internal tissues with intermingled white spots may be seen. The internal colour becomes brown, pith cavity become larger, greyish hyphae inside pith become visible. A sour and alcoholic smell emanates from the infected tissues.

At a later stage, stalks become discoloured and hollow. Acervuli (black fruiting bodies) develop on rind and nodes. After splitting open the diseased stalk, a sour smell emanates. The internal tissues are reddened with intermingled transverse white spots. In advanced stage of the disease, the colour becomes earthy brown with pith cavity in the centre showing white cottony hyphae and sometimes fruiting bodies of fungus (acervuli). In rainy season, the disease spreads so fast that whole crop dries and not a single millable cane is obtai

Survival and spread

In rainy season, the disease spreads so fast that whole crop dries and not a single milleable cane is obtained

Favourable conditions

Primary transmission through soil and diseased setts, while the secondary transmission through air, rain splash and soil.

Control:

Plant resistant varieties

Collect healthy seed material

Treat the setts with a good fungicide by dipping them for 15-20 minutes in the solution.

For controlling secondary spread of the disease:

Rogue out the diseased stools and burn them. Don't burry them.

Soak the spot of the rogued plants with fungicide.

Spray the crop immediately after seeing the disease symptoms.

Burn the trash of the diseased crop immediately after harvest.

Rotating sugarcane with other crop would be good to further devastate the disease spread.

Do not keep the ratoon of the diseased crop.

Cultivation of resistant varieties like Co 89003, Co 98014, Co 0118, Co 0238, Co 0239, Co 0124, etc will contain the disease.

2. The disease spread through infected setts. Therefore, always select seed canes from a disease free healthy crop. Any setts showing reddening at the cut ends or at the nodal region should be discarded.

3. Raise seed crop from the seed canes treated in moist hot aerated therapy unit at 54°C for 1 hour or soak the setts overnight in Thiophanate Methyl (ROKO)+Pseudomonas.

4. Resort to crop rotation with paddy and green manure crops. Avoid ratooning. This is one of the most severe of the known diseases of sugarcane.p rotation with paddy and green manure crops. Avoid ratooing.