Guidelines for checking the fruit for SWD larvae
Rutgers instructions for checking for SWD larvae in blueberries
• A recent edition of the Rutgers Blueberry Bulletin lays out their step by step instructions for checking blueberry fruit for SWD.
• It uses the same type of salt water method we’ve listed below but includes a lot of more specific details that might be helpful in standardizing this process especially for fruit receiving stations/processors.
• Click here for the 7/23/12 newsletter. The method is on pages 4 and 5.
These suggestions are based on techniques that various public researchers and industry personnel have been developing over the past couple of years. If any of you have ideas for improvements to these protocols, please pass them along.
For scouts/field checking (We have created a video of this larvae-checking method.):
•Collect a sample of fruit to be tested (Strawberries: 25-30 per sample, Caneberries/blueberries: 75 per sample)
• Put fruit in a gallon size sealable plastic bag.
• Pour in enough of the salt water solution to allow the fruit to float (solution is: 1 cup of salt per gallon of water).
• Mark bag with field code/date.
• For a quick check in the field after a designated period of time (at least 15 minutes) holding the baggie up to light. This helps to see the larvae in the solution
• For a more thorough examination, after a designated period of time (at least 15 minutes), pour the fruit and salt solution out into a shallow tray and use a piece of wire mesh screen to hold the fruit down making it easier to separate the larvae from the fruit.
For processors or fruit handling stations:
• Collect a two pound sample of fruit to be tested.
• Put the sample into a shallow tray and cover with the salt water solution (1 cup of salt per gallon of water).
• After a designated period of time (at least 15 minutes) use a piece of wire mesh screen to hold the fruit down to make it easier to separate the larvae from the fruit.
For more information about SWD, visit these websites:
• Peerbolt Crop Management
• Oregon State University
• British Columbia Ministry of Agriculture
• Washington State University Westside
• Washington State University Eastside
Updated September 12, 2012