Juvenile

The Juvenile phase in Lentil represents the developmental period from Emergence to FloralInitiation. During this phase, the plant is unable to transition to reproductive development, regardless of environmental conditions.

Overview

The GenericPhase model simulates the juvenile phase using daily Thermal Time.

  • This phase starts at Emergence and ends at FloralInitiation
  • The model uses daily thermal time, retrieved from the [Phenology].ThermalTime function
  • The Target thermal time is cultivar-specific and determined by [Phenology].JuvenileBase
  • Node appearance and leaf development continue during this phase
  • The plant is not responsive to photoperiod during the juvenile phase

Juvenile Stage Characteristics

During the juvenile stage:

  • Vegetative growth dominates, with continuous leaf and node development
  • Root system expands to explore a greater volume of soil
  • Plant is insensitive to photoperiod signals
  • Once juvenile phase ends, the plant becomes competent for reproductive transitions
  • Duration varies by cultivar

Cultivar-Specific Parameters

Name Description Default Value
[Phenology].JuvenileBase Accumulated thermal time to complete juvenile phase (°Cd) 400

Practical Considerations

The juvenile phase duration affects:

  1. Time to flowering: Longer juvenile phases delay flowering or reproductive development
  2. Seasonal adaptation: Longer juvenile phases ensure plants don’t flower prematurely
  3. Cultivar differences: Different lentil cultivars have varying juvenile phase lengths for adaptation to different regions

Understanding the juvenile phase is important for predicting flowering time under different seasonal conditions.