The latest edition of AHDB Aphid News has just been released - for the week ending 18 June.
The weather pattern returned to warm and settled after the wet and windy interlude, with it came a revived flush of aphid flight activity. This might be short lived as the subsequent heatwave may be too hot for some to handle, since many aphid species struggle to fly above 25°C. There are field reports of lots of parasitoids about, but fewer aphid predators at present. Monitoring crops is strongly advised as on the ground aphids will be multiplying.
- The peach–potato aphid (Myzus persicae) numbers increased this week, with highest numbers in the ST (suction traps) across eastern England. Tests continue show that 60-70% of these migrants are carrying Turnip yellows virus. Field reports suggest peach–potato aphids are now leaving maturing OSR to find alternative hosts.
- The mealy cabbage aphid was caught in both ST and YWT (yellow water traps) in low numbers. Field reports indicate numbers are below the threshold of >4% plants infested before petal fall in spring OSR.
- No currant-lettuce aphids (Nasonovia ribisnigri) were caught in the ST this week.
Numbers of the willow–carrot aphid and the parsnip aphids have gone back up this week.