• Philip

OSR Smells Funny!

The first step has been taken towards developing a commercial lure to help tackle the devastating and costly damage caused by the cabbage stem flea beetle, Psylliodes chrysocephala, so I am reliably informed!

Reading a recent report the following information was offered. “Damage is caused by both adults and their larvae, with most harm being caused by adults that migrate into crops during emergence. It is estimated that annual yield losses are currently between 5 to 15%. Furthermore, lodging, which is caused by larval feeding in the stems can be extensive with additional yield losses forthcoming.

This project will focus on identifying any volatiles such as a sex pheromone produced by adult beetles that elicit an attractive response in one or both sexes. If this is successful, future work will then shift to testing the volatile components in the field. The identification of biologically active volatile chemicals would improve the monitoring of this pest and may also form the basis of novel controls that could be used to reduce the damage caused by this species to oilseed rape crops.”

All this sounds great but at the moment all I can see is that those people with drilling dates in July and early August have a somewhat significantly higher larval infestation that those who did not.

Field observations clearly show (as per these photographs) crops of rape when drilled late, having low levels of larval infestation when compared to those that, on first appearances, have had pigeon grazing and frost damage. However closer inspection reveals “leaf drop” is occurring as a result of larval mining of the petiole not the former.