Brassica pod midge

  • Mosquito with 1.5-2 mm very small and inconspicuous. Bad flyer, therefore concentrated on the edges of the fields. Usually only active from middle/end flowering in places sheltered from the wind. Larvae 2 mm long, legless and headless. pupating in the ground, hatching and development of a 2nd and sometimes 3rd generation.
  • Mosquito harmless, but larvae suck on inner pod walls. Pods burst open prematurely and fungus. Margins and main shoot are most affected.

 

CONTROL BENCHMARK

  • Hardly to control, because mosquito is not detected via yellow trap. Mosquito is also easy to confuse with ichneumon flies. 
  • Exploits cabbage seed weevil oviposition sites, therefore indirect control of the midge through treatment. Midge can bite very young pods but also directly!
  • Small fields and sheltered locations more heavily infested, concentrated on large fields - especially to previous year's rapeseed. Edge treatment often sufficient. 
  • Appears mostly after the optimal Sclerotinia control date. Additional late passage usually uneconomical.
  • Larvae can no longer be controlled. 

PREVENTION

  • The most important natural enemies are ichneumon flies, ground beetles on the ground as well as nematodes and soil fungi.
  • Turning tillage buries part of the mosquito cocoons.
     

Brassica pod midge
 Brassica pod midge
 
Up to 30 first white, later yellowish larvae/pod
 Up to 30 first white, later yellowish larvae/pod
 
Mosquito active in calm and warmer conditions
 Mosquito active in calm and warmer conditions