SCEPTREplus: Cane fruit

Control of raspberry cane midge and blackberry leaf midge

• Crop: Raspberry and blackberry
• Target: Raspberry cane midge (Resseliella theobaldi) and blackberry leaf midge (Dasineura plicatrix)
• Period: June-December 2017

Take home message

• Consider using nylon ground sheeting, particularly if preparing an area for new polytunnels
• Use pheromone traps to monitor adult midge populations and apply insecticides once thresholds have been reached. The most important generation to control is the first of the season.
• Adults are much easier to hit with sprays than the larval stages, which are protected under bark or by leaf galls. Timing is key
• To reduce the damage from raspberry cane midge, select varieties that don’t tend to split

Trial summary

This technical review has looked at current and potential new control strategies. The aim is to find convention, novel and other control strategies that are compatible with an integrated pest management programme (IPM) and that could be used in the UK.

Raspberry cane midge can damage canes that leads to midge blight. IPM products are needed to control the pest as a number of the currently available plant protection products can impact the biological control of mites.

Preventing spotted wing drosophila laying eggs

• Crops: Blueberry and blackberry, but relevant to soft fruit, stone fruit and grapes
• Target: Spotted wing drosophila (Drosophila suzukii)
• Period: January - March 2018

Take home message

AHDB9931 and Urtica showed greatest potential to reduce the emergence of spotted wing drosophila (SWD).

Further testing is required on different crops to validate the results

Trial summary

The aim of the project was to test whether products can act as egg laying deterrents for SWD or reduce their emergence.

Seven different chemical treatments were tested in a laboratory.

A further study on the most promising treatments proved inconclusive.

• Crops: A range of crops (Strawberry, cherry, raspberry, blackberry, apple, pear, blackcurrant, cucumber, celery, potato, tomato)
• Target: Capsid bugs
• Period: Sept 2018 – Jan 2019

Management of these pests currently relies on application of broad-spectrum insecticides. These can be effective at killing capsids, but also reduces numbers of the naturally-occurring and released natural enemies to control other pests.

This review aims to identify capsid control options that may form basis of further research including efficacy trials.

Conclusions

• Insecticides with more selective activity against sap-feeding pests, and lower impact on beneficial natural enemies (e.g. sulfoxaflor and flonicamid) have become preferred interventions for capsids in Australia and the USA
• Novel insecticides with alternative modes of action are available for testing against capsid pests
• Improved formulation of insecticides may be possible. This may be achieved by mixing with salt or enclosing them in attractant-coated microcapsules
• The entomopathogenic fungi Beauveria bassiana and Metarhizium brunneum are available as commercial formulations and should also be considered as candidates for inclusion in efficacy testing.
• Particular weeds (e.g. nettles) are assumed to be linked with capsids and control of these is recommended
• More information is needed on the role played by natural enemies
• Semiochemical-based approaches (including push-pull strategies and pheromone based monitoring traps) have been developed for capsids as part of previous AHDB-funded work and have potential for further refinement