Disease management should be integrated into the crop production system using diverse approaches (Tables 1-3).
Table 1. Management options for common viral diseases on rice
| DISEASES | MANAGEMENT OPTIONS |
|---|---|
| Tungro | Rogue or pull out diseased plants during the first six weeks of crop growth and properly dispose of immediately to remove the source of inoculums Plant resistant varieties in tungro hot spot (e.g. Matatag) |
| Grassy stunt | Plant in synchrony with neighboring farmers Practice rice free period for at least a month between rice croppings Dry the field to destroy weeds and stubbles |
| Ragged stunt | Plow under rice stubbles immediately after harvest to prevent ratoon growth, which is a disease source and breeding place for insect transmitters Manage insect vector. Apply insecticide if needed. |
Table 2. Management options for bacterial diseases on rice
| DISEASES | MANAGEMENT OPTIONS |
|---|---|
| Bacterial blight | Plant resistant varieties Reduce plant injury during transplanting Avoid high Nitrogen fertilization Destroy infected plant residues |
| Bacterial leaf streak | Plant resistant varieties Avoid high Nitrogen fertilization Destroy infected plant residues |
Table 3. Management options for fungal diseases on rice
| DISEASES | MANAGEMENT OPTIONS |
|---|---|
| Blast | Plant resistant varieties Avoid high nitrogen fertilization Plow under rice stubbles immediately after harvest Apply soil amendment material such as silicate fertilizer with compost Apply fungicides at the right time if necessary Use healthy seeds |
| Sheath blight | Avoid high N fertilization Plow deeply to bury infected stubbles and weeds Expose soil to intense sunlight in between plowings Avoid dense stands Use healthy seeds |
| Bakanae | Treat seeds with systemic fungicide Plant resistant variety Use healthy seeds |
| Brown spot | Plant resistant varieties Practice proper agronomic practices such as balanced fertilization, field sanitation, good water management, soil amendments good soil preparation, land leveling, and other cultural practices Apply calcium silicate and compost Destroy stubbles and weeds that act as sources of inoculums Correct stress conditions in the field Apply appropriate seed treatment fungicide |
| Sheath rot | Use healthy seeds Avoid dense planting Do not apply excessive N fertilizer Plow under diseased stubbles and weeds |
| Stem rot | Plant lodging resistant and early maturing varieties Avoid high N and P fertilizers Add potash, sodium silicate, and compost Plow until one foot deep and expose soil to intense sunlight in between plowings Drain and dry the field at tillering and early jointing stages of growth Destroy or plow under stubbles and crop residues after harvest Practice crop rotation using non-host crop Apply fungicide if necessary at the plant stems before maximum tillering |
