Minimising contentious inputs in greenhouse tomatoes

To minimise the use of copper fungicides in greenhouse tomatoes, Organic-PLUS partner the University of Thessaly in Greece is working to develop a web-based Decision Support System (DSS). By closely monitoring and simulating the environmental parameters within the greenhouse, such as humidity and leaf temperature, the DSS can predict in advance when conditions conducive to the development of Botrytis disease will occur. This early warning gives the grower vital information and opportunity to make the necessary decisions.

The development of Botrytis has been shown to correlate strongly with the microclimate surrounding the crop. By closely monitoring environmental aspects such as humidity in the immediate vicinity of the plants, it is possible to identify the onset of conditions that are conducive to the disease and take preventative action such as improving airflow. Only if such prevention management actions fail should biological or chemical measures like copper fungicide be used to control Botrytis cinerea. By reducing the number of applications, the DSS can reduce production costs and environmental impact of tomato production without compromising disease control or yield.

Innovative Predictions

The innovative part of this work, is that estimates, in advance, the risk for disease development using modelling and data available from previous studies. The DSS simulates the likely greenhouse microclimate conditions in the near future, taking into account: the outside weather forecast, the greenhouse energy and vapor balance, the greenhouse control concept and methodology, the climate control equipment and the greenhouse climate set points set by the grower. Based on the predictions for the health of the crop in the next 5 days (diagram below), the DSS will propose actions that the grower can take such as climate control adjustments to prevent fungi development before resorting to the use of crop protection products.

An effective DSS can be incorporated into disease management plans, enabling greenhouse managers and growers to easily access comprehensive information that will help them decide the best course of action; they will have the opportunity to modify the greenhouse environment before resorting to plant protection products.

In order to test and assess the effectiveness of the DSS system being developed, greenhouse climate monitoring stations have been created at two test sites from which they upload their data to the specially developed software. One of these is at a high-specification greenhouse growing hydroponically cultivated tomatoes and cucumbers at the University of Thessaly in Valestino, Greece. The second has been installed at Organic-PLUS partner, the Food and Agricultural Research and Training Institute (IFAPA) in Almeria, Spain; conditions here are somewhat different with crops growing in the soil, as they would in an organically certified setting. As the Organic-PLUS project progresses, there will be more dissemination events and information published about this DSS.

Nikolaos Katsoulas and Dimitrios Antoniadis of UTH and Jens Grønbech Hansen of AU.