Cumin Yellowing Challenge Quiz

Explore common diseases that cause yellowing in cumin crops and learn to distinguish symptoms, causes, and management strategies. Perfect for growers and students seeking to protect cumin yields from major threats.

1. Downy Mildew in Cumin

   A cumin farmer notices yellow patches on leaves with a grayish fungal growth on the underside during cool, humid weather. Which disease is most likely responsible?

   1. Rust
   2. Downy mildew
   3. Powdery mildew
   4. Wilt

   Explanation: Downy mildew commonly affects cumin in cool, moist conditions, causing yellow leaf patches and a grayish growth underneath. Powdery mildew appears as white powdery spots, rust produces reddish-brown pustules, and wilt usually causes overall plant yellowing with wilting, not grayish growth.

2. Fusarium Wilt Symptoms

   Which cumin disease typically causes yellowing and wilting of whole plants, often progressing from the base upwards with brown streaks inside the stem?

   1. Alternaria blight
   2. Leaf blight
   3. Root knot nematode
   4. Fusarium wilt

   Explanation: Fusarium wilt leads to progressive yellowing and wilting, especially from the plant base, with brown discoloration inside stems. Leaf blight mainly affects leaf surfaces, Alternaria blight causes spots rather than widespread wilting, and root knot nematode creates root galls.

3. Alternaria Blight Impact

   If small, circular yellow-spotted lesions appear on cumin leaves and later turn brown with concentric rings, which disease is most likely present?

   1. Cercospora leaf spot
   2. Sclerotinia rot
   3. Alternaria blight
   4. Bacterial blight

   Explanation: Alternaria blight is characterized by yellow spots evolving into brown, ringed lesions. Bacterial blight usually forms water-soaked spots, Cercospora creates angular leaf spots, and Sclerotinia rot leads to soft, watery decay rather than rings.

4. Root Knot Nematode Effects

   What is a typical above-ground symptom of root knot nematode infestation in cumin, often observed before digging up plants?

   1. Red-orange pustules on stems
   2. Wet rot of stem base
   3. Stunted, yellowing plants with patchy field distribution
   4. Powdery white coating on leaves

   Explanation: Root knot nematode causes stunted growth and yellowing in irregular patches due to root damage. Powdery coatings are due to powdery mildew, pustules are rust symptoms, and wet rot is linked to soft rot pathogens.

5. Disease Management Practices

   Which single practice is most effective for minimizing yellowing diseases in cumin fields?

   1. Excessive irrigation
   2. Rotation with non-host crops
   3. Continuous monocropping of cumin
   4. Applying random fertilizers

   Explanation: Crop rotation interrupts disease cycles by starving pathogens of their preferred host. Monocropping increases disease risk, excessive irrigation can worsen disease spread, and random fertilizer use does not target disease prevention.