RAPID ACCESS TO THE LATEST REGIONAL CROP PEST AND DISEASE LEVELS 		HGCA logo
CropMonitor > Winter Oilseed rape > National Surveys  


2006/2007 SURVEY: SPRING/SUMMER PEST ASSESSMENT 2007

2ND VISIT: MID-LATE FLOWERING (Latest update: 03/05/2007)

 
Unsprayed crops at mid-late flowering were inspected for Cabbage Seed Weevil.
A total of 43 sites were inspected for this second spring/summer assessment.
 
It is at the mid-late flowering growth stage that the decision to take action against Cabbage Seed Weevil needs to be made. The adults do not cause any economic feeding damage, but will lay their eggs on the developing pods and their larvae feed on the seeds.
Site Location Number of sites Cabbage Seed Weevil per plant per site Maximum Cabbage Seed Weevil per plant
North 9 0.46 1.0
East 8 0.21 0.45
Midlands & West 13 0.21 0.5
South-East 9 0.04 0.25
South-West 4 0.125 0.2
mean of all 43 sites 0.22 1.00
 
Thresholds
Published thresholds are 2 per plant, unless the site has a history of Brassica Pod Midge problems. If this is the case the threshold drops to 1 per plant

If the temperature in the crop is between 11ºC and 15ºC, multiply the mean per plant by 2.26 before considering the threshold value.

Number of sites with more than 2 cabbage seed weevil per plant:0 (0%)
Number of sites with 1 or more cabbage seed weevil per plant:1 (2.33%)

 
Defra Logo delivered to the industry by HGCA
This website was last updated on: 07/08/2008     © Crown Copyright Central Science Laboratory 2007
CSL Logo
All risk predictions published by CropMonitor are provided in good faith and are NOT a substitute for rigorous fieldwalking in combination with advice from BASIS qualified persons. CropMonitor accepts no liability for crop loss or damage resulting from the use of CropMonitor.