Disease Breakdown:

1. Bacterial Soft Rot

   • Cause: Caused by bacterial pathogens like Erwinia chrysanthemi.
   • Appearance: Occurs during the early growth stage, especially under wet conditions.
   • Harm: Leads to rotting of the stalk and softening of affected tissues.
   • Fungicides: Copper-based products and Streptomycin help control bacterial infection.

2. Charcoal Rot

   • Cause: Fungal pathogen Macrophomina phaseolina.
   • Appearance: Typically appears during the late vegetative stage to early reproductive stage.
   • Harm: Causes stunted growth and premature death, which leads to reduced yield.
   • Fungicides: Azoxystrobin, Tebuconazole, and Propiconazole are effective for prevention.

3. Common Rust

   • Cause: Puccinia sorghi fungus.
   • Appearance: Appears late in the vegetative stage to early reproductive stage.
   • Harm: Yellow streaks on leaves and yield loss.
   • Fungicides: Chlorothalonil, Mancozeb, and Propiconazole provide effective control.

4. Common Smut

   • Cause: Ustilago maydis fungus.
   • Appearance: Occurs during the silking stage.
   • Harm: Tumors on ears and kernels, leading to reduced grain quality.
   • Fungicides: Tebuconazole and Azoxystrobin are effective treatments.

5. Corn Dwarfing

   • Cause: Virus, typically the Maize Dwarf Mosaic Virus.
   • Appearance: Early in the vegetative stage.
   • Harm: Stunted growth, yellowing of leaves, and poor ear development.
   • Fungicides: No specific fungicides; control is achieved by managing aphids (vector) using insecticides.

6. Root Rot

   • Cause: Various fungi such as Fusarium and Pythium species.
   • Appearance: Occurs early in the vegetative stage (seedling emergence).
   • Harm: Weakens root systems, reducing nutrient uptake and causing stunting.
   • Fungicides: Metalaxyl, Mefenoxam, and Fosetyl-Al are commonly used to control this issue.

7. Fusarium Ear Rot

   • Cause: Fusarium verticillioides fungus.
   • Appearance: Appears during the flowering and grain-fill stages.
   • Harm: Grain contamination with mycotoxins, leading to quality loss.
   • Fungicides: Propiconazole and Tebuconazole are recommended for control.

8. Fusarium Stalk Rot

   • Cause: Fusarium fungi.
   • Appearance: Found during late vegetative to early reproductive stages.
   • Harm: Weakens the stalks, causing lodging and reduced yield.
   • Fungicides: Azoxystrobin, Tebuconazole, and Propiconazole are effective treatments.

9. Head Smut

   • Cause: Sphacelotheca reiliana fungus.
   • Appearance: During the flowering and silking stages.
   • Harm: Tumors or growths on the ear, reducing yield and grain quality.
   • Fungicides: Tebuconazole and Azoxystrobin help in controlling head smut.

10. Maize Dwarf Mosaic

    • Cause: Virus, usually Maize Dwarf Mosaic Virus.
    • Appearance: Early vegetative stage.
    • Harm: Stunted growth and poor ear development.
    • Fungicides: No fungicide control, but managing aphids with insecticides helps reduce virus spread.

11. Pythium Stem Rot

    • Cause: Pythium spp. fungi.
    • Appearance: Seen in early to mid-vegetative stages.
    • Harm: Softening of the stem, yellowing, and plant death.
    • Fungicides: Metalaxyl, Mefenoxam, and Fosetyl-Al are effective for treatment.

12. Seed Rot and Seedling Blight

    • Cause: Fungi like Fusarium, Pythium, and Rhizoctonia.
    • Appearance: Early in the growth stage (seedling emergence).
    • Harm: Seedling death, poor plant establishment, and stunted growth.
    • Fungicides: Metalaxyl, Thiram, and Captan are effective in controlling this problem.