Question

Give the reason for the appearance of whiptail disease in cauliflower.

Hint:

If you see cauliflower plants with narrow, twisted leaves resembling whips, suspect molybdenum deficiency. The quickest remedy is a foliar spray of sodium molybdate (0.05%). For long-term control, lime acidic soils to pH 6.5-7.0 to make molybdenum more available to plants.

Answer 1

Whiptail Disease in Cauliflower

Whiptail is a physiological disorder commonly seen in cauliflower and other cruciferous crops. It is mainly caused by molybdenum (Mo) deficiency in the soil.

Reason:
Molybdenum is essential for nitrogen metabolism. It is a component of the enzyme nitrate reductase, which helps convert nitrate (NO3-) into usable nitrogen forms for protein synthesis. When molybdenum is deficient:

• Nitrate accumulates in plant tissues.
• Protein synthesis is disturbed.
• Plant growth becomes abnormal.

Symptoms:

• Narrow, strap-like leaves (whiptail appearance)
• Poor lamina development
• Leaf curling and distortion
• Stunted growth
• Poor or no curd formation
• Chlorosis in young leaves

Causes of Deficiency:

• Acidic soils (pH below 6.0)
• Leached sandy soils
• Low organic matter

Control Measures:

• Liming to maintain soil pH 6.5–7.0
• Application of sodium or ammonium molybdate
• Foliar spray (0.05%–0.1% solution)
• Addition of organic matter

Conclusion:
Whiptail disease is caused by molybdenum deficiency, especially in acidic soils, and can be controlled by correcting soil pH and applying molybdenum.