The BBCH code is a standardized, decimal system for the uniform description
of phenological
growth stages of plants. "BBCH" originates from the collaboration of the former Biologische
Bundesanstalt (Germany), Bundessortenamt (Germany), and CHemical Industry.
Purpose and Use:
- Standardized Communication: Provides
a universal "language" for researchers, agronomists,
farmers, and industry to precisely describe a plant's developmental stage, regardless of
location or crop.
- Timing Management Practices: Critical
for scheduling key agronomic operations (e.g., fertilizer
application, irrigation, pest/disease control, growth regulator use, harvest) at the correct
physiological stage.
- Scientific Studies: Ensures reproducibility
in experiments by accurately documenting the plant
stage at the time of measurements or treatments.
Structure of the Code:
The code is a two-digit decimal system (XX).
- Principal Growth Stage (First Digit,
0–9): Describes the major phase of development.
0: Germination / sprouting / bud development
1: Leaf development (main shoot)
2: Formation of side shoots / tillering
3: Stem elongation / shoot development
4: Development of harvestable vegetative parts / booting
5: Inflorescence emergence / heading
6: Flowering
7: Development of fruit
8: Ripening or maturity of fruit and seed
9: Senescence, beginning of dormancy
- Secondary Growth Stage (Second Digit,
0–9): Subdivides the principal stage, indicating the
progress within that phase (typically from 0=beginning to 9=completion).
Example for Wheat:
BBCH 13: 3 leaves unfolded on main shoot.
BBCH 39: Flag leaf ligule/collar just visible.
BBCH 65: Full flowering: 50% of flowers open.
Importance in Plant Nutrition:
Nutrient demand, uptake efficiency, and the risk of deficiency or toxicity vary dramatically
with
growth stage. The BBCH code allows for:
- Stage-Specific Fertilization: Applying
nutrients when the plant's demand is highest (e.g., N at
stem elongation in cereals, BBCH 30-39).
- Accurate Tissue Sampling: Standardizing
the plant part and stage for tissue analysis (e.g.,
sampling at BBCH 31-33 for wheat).
- Interpretation of Results: Understanding
nutrient concentrations in the context of the plant's
physiological age.
- Modeling: Serving as an input for
crop growth and nutrient uptake models.
In summary, the BBCH code is an indispensable tool in modern agronomy and
plant
science, providing the precise temporal framework needed for effective and efficient crop
management, including optimized nutrient application.
