Bean bruchid alert
Bruchids are present in crops and most crops are approaching pod-set or have set first pods. Temperature is forecast to reach 20°C at the end of the week in some regions. Crops should be sprayed when maximum daily temperature has reached at least 20°C for two consecutive days and when crops have set first pods (when 50% pods on the bottom trusses are 2cm long). Sign up for bruchid spray forecasts in your area by going to http://www3.syngenta.com/.../BruchidCast.aspx.
There have been reports of a few pea moths in traps across the UK and some may have reached the threshold of 10 moths in either trap on two consecutive occasions.
Pea moth spray date forecasts can be found for your region at http://www.pgro.org/index.php/pest-monitoring-services/pea-moth
Silver Y moth
First catches of silver Y moth at our monitoring site in Leicestershire were on Monday 25th May and a threshold of 50 moths (cumulative total) was caught by 5th June. If you reach a threshold in your area by the time crops have reached first pod stage, sprays should be applied 10 to 14 days later to control both small and large caterpillars in vining peas.
Black bean aphid is being reported in crops across the country at medium to high levels. If there is a general distribution within the crop of 10% plants infested, aphicides should be applied to prevent yield loss. If there is a history of virus infection in crops, sprays should be applied when 5% plants are infested.
Pea aphid is present in peas and may also affect beans. In combining peas, sprays should be applied when 20% plants are infested, and in vining peas when 15% are infested.
Downy mildew is being reported in spring beans, with sporadic infections being reported in winter beans. In cases where 25% or more plants are infected in winter or spring beans, particularly on new growth, SL567A (metalaxyl-M) will give good control of downy mildew and should be combined with a partner fungicide product. Live forecasts for bean downy mildew risk in your area are available on the CropMonitor website at www.cropmonitor.co.uk
The current forecast is for moderate risk of infection in all areas of the UK.
PGRO is investigating races of downy mildew present in UK pea crops and would like to request that growers send plant samples with downy mildew infection to our laboratory, labelled with location and variety. Please send samples to Keith Poulson at PGRO, The Research Station, Great North Road, Thornhaugh, Peterborough, PE8 6HJ or call 01780 782585.