The weather conditions have an important role in the development of many social and economic activities. Forecasting of weather conditions can be useful to plan activities especially during extreme events as such information can help to react in time and, consequently, support businesses which are weather-sensitive. This is the case of the wine sector; whose production and crop quality highly depend on the weather conditions.

In this context, weather forecasting becomes of a paramount importance and provides added-value to the end-users to manage their resources and in-field activities and to anticipate potential extreme events.

On 29^th October 2020, VISCA consortium organized an e-Workshop to present the latest release of VISCA Decision Support System (DSS) & its added value through a live demo. The DSS is a Progressive Web Application which integrates climate and agricultural models with farmers’ management specifications in order to design short practices, medium- and long-term adaptation strategies to climate change. The live demo showed the integrated dashboard of the DSS with its 3 main widgets (phenology, irrigation and weather forecasts) as well as the features in relation to the map-based visualization.

Furthermore, the preliminary results and key findings were presented from the demonstration sites in Italy, Portugal and Spain in terms of the validation of the DSS as well as the results from the agronomic techniques: crop forcing and shoot trimming. In addition to that, the commercial opportunities and exploitation options were briefly discussed.

A new scientific article has been published entitled "The pitfalls of water potential for irrigation scheduling".

Abstract: The water potential (Ψp), has been widely used as an indicator of plant water status for irrigation management purposes. The simple infrastructure needed for its measurement and its direct relation to basic plant physiological processes, have contributed to the popularity of the methodology. When used for irrigation scheduling, it is commonly assumed that an unavoidable relationship exists between plant transpiration (T), soil water content and Ψp. Nevertheless, it is worth remembering that variations in Ψp are not solely related to changes in soil water content, but are also an expression of the interaction between the plant and its environment. We used a soilplant-atmosphere-continuum (SPAC) model to highlight the importance of considering such interactions through a series of in silico experiments. Our analysis shows that evaporative demand, the hydraulic architecture of the plant, and the texture and depth of the soil play key roles in the final Ψp observed. To establish irrigation programs based on Ψp, without considering the environmental and plant factors that influence it, can create the paradox of having a plant that suffers greater water stress even when high irrigation volumes are applied. The conclusions from our in silico analysis provide some warnings that should be considered when using Ψp to schedule irrigation.

Download the full article from here

VISCA DSS is integrating climate and agricultural models with farmers’ management specifications in order to design short practices, medium- and long-term adaptation strategies to climate change.

The irrigation widget included in VISCA DSS provides recommendations for weekly irrigation needs based on plant and end-user requirements. This component of the tool has supported the irrigation management across the demonstration sites in Italy, Portugal and Spain. The irrigation model takes into account the plant physiological characteristics, the end-users’ necessities, and the irrigation and weather data during the growing season, to provide accurate irrigation volume forecasts for the next week. The model uses the midterm (weekly) weather predictions which is also included in VISCA DSS.

Figure1. Example of irrigation applied by the end user (purple line and bars) and predicted by the DSS (green line and bars) on an irrigation block at CODORNIU (Spain)

The irrigation widget in VISCA DSS allows the end-users to have an easy access to the irrigation data. The irrigation widget is divided into three panels (Figure 1). The left hand panel has an interactive map which shows the irrigation block selected in the parcel. The central panel presents the accumulated irrigation predicted (green line) and applied by the end user (purple line) and the right hand panel presents the weekly irrigation applied (purple bar) and forecasted by the VISCA irrigation model (green line).

What would happened if this forecast is not available (Business as Usual scenario)?

VISCA DSS is integrating climate and agricultural models with farmers’ management specifications in order to design short practices, medium- and long-term adaptation strategies to climate change.

In the Irpinia Valley, located in south of Italy (about 60 km from Naples), a very warm winter influenced the precocity of the budbreak that occurred one week earlier than average. Also, blooming advanced earlier followed by a rainy month of June with some problems of downy mildew. However, with the predictions supplied by VISCA DSS, the Mastroberardino viticulture team was able to contain the disease by increasing the number of treatments sprays, anticipating the action as the prediction of several days of rainfall was given.

VISCA DSS showing that bud break and blooming have been achieved and earlier than normal (July 2020)

Blooming observed in the field - Italian Demo Site (July 2020)

This summer, VISCA DSS, in particular the short-term and mid-term climate forecasts, has predicted lower precipitation than normal and higher temperature than normal in Mirabella Eclano estate in the Campania region, where our Italian demonstration site is located. Before the phenological phase of blooming, the DSS, through the seasonal forecast, predicted a dry and hotter summer than normal, followed by the months of September and October with the same trend. Aglianico is the grapevine under the VISCA experimental plot and it is extremely sensible to powdery mildew disease. The dry season usually influences the development of the fungus directly on the grapes. Therefore, such useful predictions allowed the Mastroberardino vinegrowers to take decisions about the canopy and vineyards management in advance. First of all they programmed:

Crop forcing is based on moving the grape-ripening period from hot summer months to a cooler month later in the growing season. This is achieved by making an additional pruning, stopping the natural cycle of the plant and “forcing” it to restart its phenology (bud break, bloom, fruit set and so on). Shifting the ripening to a cooler month couples sugar accumulation with flavour and aroma development improving the quality of the grapes

This June, crop forcing has been successfully applied in our Spanish Demo site in Raimat in order to move the grape-ripening to October. According to VISCA DSS, performing the crop forcing at the beginning of June will move veraison from the last week of July to the mid October. In our Mediterranean climate, summers are characterized by hot and dry weather conditions, with temperature values that can be as high as 40 ºC. In Autumn, the temperature drops. The cooler weather conditions allow an optimum balance between sugar and flavor in the berry.  

The VISCA DSS tool is presenting this phenological cycles of the vineyards and taking into consideration the applied agronomic technique which is fed by the end-users:

VISCA DSS shows the phenology stage before crop forcing 

VISCA DSS shows the phenology stage after crop forcing 

What would happened if this forecast is not available (Business as Usual scenario)?

Without a tool like VISCA DSS, we cannot explore the optimum pruning date to implement the crop forcing. Having a seasonal forecast linked to phenological models provide a useful guideline to decide the optimum date to perform the crop forcing.

VISCA DSS is integrating climate and agricultural models with farmers’ management specifications in order to design short practices, medium- and long-term adaptation strategies to climate change.

In the Douro Valley, where our Portuguese demonstration site is located, the combination of abundant rainfall in March and April of 2020 and a very warm winter influenced the precocity of this year’s growth cycle, with budbreak recorded three weeks earlier than average. These conditions caused recurrent and earlier than expected outbreaks of downy mildew. However, with the predictions supplied by VISCA, the Symington viticulture team was able to plan a very effective treatment schedule, which successfully contained the disease.

Flowering also advanced earlier, arriving two weeks ahead of the regional average, and in order to safeguard good fruit set and ensure a healthy crop, the team at Symington continues to rely on timely VISCA predictions to plan ahead and keep disease pressures at bay.

DSS showing that budbreak has been achieved (May 2020)

Pictures of Ataíde vineyard of first week of May 2020 showing the phenological stage of bloom

During April, VISCA DSS predicted higher rainfall than normal in Douro. This increase of precipitation would risk the spread of grape diseases causing some loss of crops. To avoid this loss, the Viticulturists of Symington have decided to make 4 treatments sprays instead of 3 with an earlier positioning than usual in the calendar, to block the downy mildew cycle.

VISCA project has been developing a Decision Support System (DSS) that integrates climate and agricultural models with farmers’ management specifications in order to design short practices, medium- and long-term adaptation strategies to climate change. After more than three years since the launch of our project, we are publishing the ‘VISCA Booklet on Preliminary Results’. The booklet gives an overview of the project, a description of the DSS and the integrated climate services, the added value of these services with testimonies from the end-users as well as the preliminary results driven from the demonstration sites in Italy, Portugal and Spain. The booklet also presents an overview of the replicability and the way forward (exploitation). You may download VISCA Booklet here.