18.104.22.168. Marking SHB larvae
Coloured food is a good method to mark SHB larvae.
- Dissolve 1 g of the dye (Sudan Blue 670, Sudan M Red, Rhodamine B; S. Spiewok, unpublished data) in 9 g olive oil to obtain a stock solution.
- Stir 3 g stock solution into 57 g honey.
- Mix the honey with 90 g powdered pollen to obtain dye-concentrations of 2,000 ppm.
- Fill 10 g of the coloured food into small containers with lids ventilated with tiny holes that allow airflow but prevent escape of SHB larvae.
- Place 10 young larvae (see section 22.214.171.124.) into each container and incubate for 8 days at 30°C till they reach the wandering stage.
larvae fed with Sudan Blue 670 will show green coloration. Sudan M Red results
in reddish and Rhodamine B in violet coloured larvae.
Note: Feeding SHB larvae with food colours showed no decent results in the adults after metamorphosis (S. Spiewok, unpublished data).