SCEPTREplus: Asparagus

• Crop Group: Field vegetables – asparagus
• Target: Asparagus beetle
• Period: June 2017 – June 2018

All of the products tested were effective against asparagus beetle larvae. There were only small differences between conventional insecticides and bio-insecticides.

Adults were more difficult to kill. All of the bio-insecticides and the standard control option, cypermethrin, were largely ineffective.

Of the conventional insecticides, initial mortality was greater with AHDB9965 and AHDB9969. However, after 6 days, there was no statistically significant difference between these two products and Benevia, Tracer and Steward.

Larvae

• All of the 12 treatments controlled larvae effectively
• Conventional treatments tended to act more quickly than the bio-insecticides and killed a greater proportion of the larvae. However, all treatments increased mortality to greater than 80%.

Adult beetles

• With no direct contact action, the adults were more difficult to kill. This is likely to be the case with field application as adult beetles are so mobile.
• Two treatments (ADDB9965 and AHDB9969) increased mortality after one day compared with the untreated control
• Four treatments (Benevia, AHDB9966, Tracer and Steward) increased mortality after four days
• None of the bio-insecticides significantly increased mortality after six days
• The most effective treatments (Tracer and AHDB9969) increased mortality to greater than 80% after six days

Inter-row

EAMU applications should be made for inter-row use of AHDB 9840 and AHDB 9976 to expand the range of actives available. This would improve weed control and reduce risk of resistance development. 

Post-harvest

The use of emerger 1.75 L/ha, AHDB 9977, AHDB 9990 or AHDB 9974 are not currently authorised for use in asparagus. By the conclusion of the trial, all showed lasting efficacy as post-harvest treatments without any persistent phytotoxic effects and would be valuable additions to growers' weed control options.