Emerging
The Emerging phase in Chickpea represents the developmental period from Germination to Emergence. This phase simulates seedling growth from the germinated seed to the point where the cotyledons break through the soil surface.
Overview
The EmergingPhase model simulates the time between Germination and Emergence stages.
- This phase starts at Germination and ends at Emergence, when the seedling emerges from the soil
- The model uses daily Thermal Time, retrieved from the
[Phenology].ThermalTimefunction - The Target thermal time to complete this phase is defined as:
\[ \text{Target} = \text{ShootLag} + (\text{SowingDepth} \times \text{ShootRate}) \]
Where:
- ShootLag is the lag period before shoot elongation begins (°Cd)
- ShootRate is the rate of shoot elongation (°Cd/mm)
- SowingDepth is the depth at which the seed is sown (mm), taken from
[Plant].SowingData.Depth
Deeper sowing results in longer emergence delays due to greater thermal time requirements.
Cultivar-Specific Parameters
| Name | Description | Default Value |
|---|---|---|
| [Phenology].Emerging.ShootLag | Lag before shoot starts to elongate (°Cd) | 120 |
| [Phenology].Emerging.ShootRate | Rate of shoot elongation (°Cd/mm) | 0.7 |
Practical Example
This table illustrates how deeper sowing delays emergence due to higher thermal time requirements:
| Sowing Depth (mm) | ShootLag (°Cd) | ShootRate (°Cd/mm) | Target Thermal Time (°Cd) |
|---|---|---|---|
| 30 | 120 | 0.7 | 141.0 |
| 50 | 120 | 0.7 | 155.0 |
| 70 | 120 | 0.7 | 169.0 |