Growth and Development of Horticultural Crops (1+1)

Conditions necessary for vernalization

Age of the plant

• It determines the responsiveness of the plant to cold stimulus and it differs in different species.
  
• In case of biennial variety of henbane (Hyoscyamus niger), the plants will respond only when they are in rosette stage and have completed at least 10 days of growth.
Appropriate low temperature and duration of the exposure

• Most suitable temperature is 1-6°C. The effectiveness decreases from 0 to -4°C. Temperature of -4°C is completely ineffective.
  
• Similarly from 7°C the response decreases. Temperature 12°C-14°C are almost ineffective in vernalizing the plants.
Oxygen

• Vernalizing is an aerobic process and requires metabolic energy. In the absence cold treatment, it becomes completely ineffective.
Water

• Sufficient amount of water is also essential. Vernalization in dry seeds is not possible.