Location
Bulb and Salad Onion: Evaluation of an integrated disease management system to ascribe risk of downy mildew disease on commercial crops in the UK

Research

CP 099c - Bulb and Salad Onion: Evaluation of an integrated disease management system to ascribe risk of downy mildew disease on commercial crops in the UK

Start Date: 
01/02/2014
Completion Date: 
31/01/2016
Project Leader: 
A. Wakeham, University of Worcester
Code: 
CP 099c

Industry representative: Andy Richardson

HDC project cost: £55,416

 

Project summary:

 

The project will assess an integrated disease management system for the control of downy mildew in UK onion crops with minimal fungicide input. The use of ‘in field’ tests (lateral flows) will be evaluated in commercial cropping systems for their accuracy in monitoring airborne downy mildew disease transmission events. These will be used in conjunction with MILIONCAST, an environmental model which defines periods at which the crop would be at risk to onion downy mildew infection, will be used in conjunction with the tests to ascribe disease risk periods. The timed application of disease control measures (fungicide applications) will be made in response to these warnings.

 
 
Benefits to industry:
 
There is considerable scope for benefit from this work in terms of early detection and improved spray timing. Salad onions have few active ingredients which can be used to control onion downy mildew. Ultimately, financial benefit will be gained through improved quality and reduced pesticide residues. In year 2 of the project the infield tests will be carried out by the grower / consultant. This will provide the opportunity for informed disease control measures to be put in place directly following a ‘risk’ period. Knowledge transfer events with ‘hands on’ use of the kit will be provided in Year 2 of the project.
 
 
Aims and objectives:
 
Project aim(s):
 
The aim of the project is to provide validation of the onion downy mildew ‘in field’ lateral flow tests in onion crops. These will be used as part of an integrated disease management system for the control of downy mildew in UK onion crops with minimal fungicide input. The use of ‘in field’ tests (lateral flows) will be evaluated in commercial cropping systems for their accuracy in monitoring airborne downy mildew disease transmission events. MILLIONCAST, an environmental model which identifies periods during which the crop would be at risk to onion downy mildew infection, will be used in conjunction with the tests to ascribe disease risk periods. The timed application of disease control measures (fungicide applications) will be made in response to these warnings.
 
Project objective(s):
 
a) Produce consistent batches of a semi quantitative lateral flow device for the measurement of onion downy mildew spore concentration. A lower limit of detection will be set as recommended in HDC FV356.
b) Monitor downy mildew spore concentration in commercial spring and bulb onion crop aerosols using laboratory processed samples (MTIST ELISA) and an ‘in field’ test system. In conjunction with an environmental model (MILIONCAST) ascribe disease risk on a weekly basis to cooperating onion producers.
c) Assess the cropping systems for onion downy mildew development following :
• Routine control spray applications
• Timed control spray applications (based on the assessment of air samples and Milioncast)
• No treatment application.
d) Develop sufficient batches of the infield test for UK commercial release in 2016.