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Forecasting Sclerotinia disease in field grown lettuce - HH3215TFV


Sclerotinia sclerotiorum causing Sclerotinia rot is a major limiting factor in growing field lettuce in the UK and in recent years, several major UK growers have been forced to cease production because of this pathogen. With a potential crop loss of 15%, this disease may cost as much as £12 million per annum based on DEFRA Horticultural Statistics. Only off-label foliar fungicides are currently available for control and a major problem in using these chemicals is in achieving effective timing of the sprays so that Sclerotinia disease is controlled and unnecessary applications are avoided.

The aim of this research is to develop a predictive model for Sclerotinia disease in lettuce based on an understanding of the environmental factors affecting apothecial production and ascospore infection. This will be a significant new step in Sclerotinia control, as periods of high disease risk in lettuce crops will be identified and this would enable rational, economic and effective use of current and future foliar fungicides. The model will have the potential for application in other Sclerotinia disease-crop systems.

This work relates to DEFRA’s policy objectives of promoting a modern, adaptable, diverse and sustainable farming industry as well as a competitive food supply chain which is responsive to the needs of consumers. This will be achieved by optimising and reducing agrochemical inputs through a contemporary approach to development of a disease forecasting model based on sound scientific data.

1. Derive relationships between environmental factors, Sclerotinia infection and disease development from existing data and develop a preliminary predictive model for infection.
2. Validate predictive model for infection and refine relationships with environmental factors by further field infection studies.
3. Derive a relationship between soil water potential, temperature and apothecial production and develop a preliminary predictive model from existing data.
4. Validate predictive model for apothecial production and refine relationships with environmental factors by further laboratory and field studies.
5. Produce a preliminary Sclerotinia disease forecasting model by combining apothecial development and infection models.

Project Documents
• Final Report : Forecasting Sclerotinia disease in field grown lettuce   (679k)
Time-Scale and Cost
From: 2003

To: 2005

Cost: £441,033
Contractor / Funded Organisations
Warwick - HRI, Horticulture Research International, ADAS UK Ltd.
Crop Diseases              
Crop Improvement              
Disease Control              
Sustainable Farming and Food              
Sustainable Production              
Fields of Study