AHDB Pest Bulletin

Pest Bulletin weekly summaries

AHDB Pest Bulletin 2021-22

With the increasing loss of the active ingredients which make up traditional chemical pesticides, integrated pest management (IPM) is becoming increasingly important across agriculture and horticulture.  The Pest Bulletin was an important part of AHDB’s IPM delivery to horticulture growers in the UK and is an integral part of the new strategy.

The AHDB Pest Bulletin consisted of a weekly e-mail, sent out during the growing season, and a web page hosted by Syngenta, which provided growers with essential pest forecasts and up-to-date reports on most of the key horticultural field crop pests, indicating periods when infestations were likely to occur, to help growers make informed pest control decisions, and minimise the use of chemical pesticides. Data was collected from various locations around the UK, giving regional information, as well as historical data to provide year-on-year comparisons of pest numbers. 

Forecasting is a vital part of IPM and the Pest Bulletin provided day degree forecasts for currant-lettuce aphid, lettuce-root aphid and willow-carrot aphid, and predicted dates for first, 10% and 50% activity of black-bean aphids. These forecasts were also provided for the start of cutworm (turnip moth) flight activity and output from the cutworm risk model. In addition, forecasts (emergence/flight activity as relevant) were produced for carrot fly, large narcissus fly and pollen beetle.

The bulletin included monitoring intelligence from Warwick Crop Centre, Wellesbourne for more than 20 species including cabbage root fly, carrot fly, pollen beetle, flea beetle, bean seed fly, willow-carrot aphid, small and large white butterfly, turnip moth, silver Y moth and diamond-back moth.

Willow-carrot aphid, for example, is the main vector of carrot viruses, so forecasting is vital for carrot growers who, due to loss of PPPs and the weather, had a particularly bad year for virus in 2020, loosing up to 30% of their crops. This also linked with work conducted in FV 460 carrot virus transmission project.

Prediction of migrant moth invasions is problematic and the Pest Bulletin provides a range of real-time data for growers. Diamond-back moths are an important pest of brassicas, which can decimate crops. As part of the Pest Bulletin, they were recorded by a network of commercial brassica growers throughout the UK using pheromone traps. The resulting data was compiled by Warwick and made available on-line. Likewise citizen science information on sightings of diamond-back moth and silver Y moth (an important pest of salad crops) in several northern European countries was compiled daily and made available to help predict moth invasions.

The same approach had been used to develop a UK wide network of growers who are using pheromone traps to monitor swede midge, a problem in brassicas that was initiated in 2020 in response to grower concerns at this increasingly important pest.