Die Modelle

The black rot model is monitoring and predicting the risk for an infection with the pathogen //Guignardia bidwellii. //As the spread of the pathogen is influenced by temperature and several other factors it makes sense to use a time based graph, which displays the necessary information. Three levels of detail (Übersicht, Kombiansicht and Detailansicht) are available to display the data in our black rot model.

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== Übersicht ==

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On the very top of the page, you will find the infections of the past days and a prediction for the upcoming days. The information is colorcoded.

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[[image:1736281174283-755.png||height="29" width="341"]]

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The numerical values represent the daily maximum infection index, calculated based on the duration of the wetness period and the temperature conditions during that time. Higher values indicate a greater severity of the infection event. The severity is indicated using the following color scheme:

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[[image:1736281197316-330.png||height="118" width="176"]]

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The "Übersicht" displays the following parameters for both the past 15 days and the forecast period:

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* **Daily average temperatures**, minimum and maximum values, daily precipitation totals, and average relative humidity.

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* **Leaf wetness (BN)**: Wetness phases are shown in blue.

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* **Infection index**: Visualized with the color scheme described above.

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* **Relative susceptibility of the berries** in percentage (from BBCH 68 onwards).

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* **Leaf count and total leaf area per shoot** (light green + dark green areas), as well as the currently growing leaf area per shoot (light green) in cm², based on the leaf area model by Schultz (2003).

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[[image:1734349475576-446.png||height="397" width="531"]]

== Kombiansicht ==

The Kombiansicht provides a summary of key information for daily vineyard management. It displays current and historical weather data alongside calculated infection and incubation events in a graph.

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The graphical overview displays the following parameters:

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=== Daily Averages, Minima, Maxima, Precipitation, and Humidity: ===

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* (((

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Daily mean, minimum, and maximum temperatures.

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* Total daily precipitation.

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* Daily average relative humidity values.

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=== Leaf Wetness (LW): ===

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* (((

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Leaf wetness phases are highlighted in blue, making it easy to identify periods of high moisture on the vine canopy.

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=== Infection Index: ===

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* (((

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The infection index is displayed using the described color coding: green (no risk), yellow (moderate risk), and red (high risk).

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=== Relative Susceptibility of Berries: ===

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* (((

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The model shows the relative susceptibility of grape berries in percentage terms starting from BBCH stage 68 (the onset of berry touch).

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=== Leaf Count and Surface Area Per Shoot: ===

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* Total number of leaves per shoot.

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* Total leaf surface area per shoot (light green + dark green areas).

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* The leaf area currently growing per shoot (light green) in square centimeters.

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These values are calculated using the leaf area model developed by H.R. Schultz (Geisenheim University), ensuring estimates of canopy development.

== Detailansicht ==

The Detailed View provides a high-resolution, hour-by-hour breakdown of key parameters. This data offers precise insights into infection dynamics and environmental conditions. Below is an expanded overview of the features, including incubation and infection metrics:

=== Inkubation ===

The "Detailansicht" tracks the progression of the incubation period for both leaves and berries, enabling accurate symptom prediction.

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a) Incubation progression on leaves (green color):

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* Symptoms on leaves are expected after an incubation period of 175 degree-days, calculated using daily mean temperatures between 6°C and 24°C.

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* The incubation period ends when the cumulative degree-days reach 175, as indicated by the ending of the green incubation line.

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b) Extended incubation progression on berries (red):

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* On berries, the incubation period is extended as berry maturity advances. This is represented by a red line that continues beyond the green incubation line.

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* The incubation period for berries ends when the red line ends.

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c) Initiation of incubation:

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* Incubation begins when the infection index exceeds 85 degree-hours, calculated using hourly average temperatures between 5°C and 20°C, for the first time on a calendar day.

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* This start date is visually marked by a purple triangle on the timeline.

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[[image:1736281280745-348.png||height="91" width="575"]]

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=== 2. Infection Index ===

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The infection index represents a dynamic measure of risk, showing the intensity and timing of infection events. This index helps identify when conditions for black rot infection are met, guiding timely intervention.

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=== 3. Meteorological Parameters ===

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The detailed view includes hourly meteorological data critical for understanding black rot risks:

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* Temperature (°C) tracks fluctuations that influence fungal activity.

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* Precipitation (mm) records rainfall that may promote spore dispersal and leaf wetness.

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