Method development of the Acute Contact Test and the Semi-Field procedure with the solitary bee species Osmia bicornis

Worldwide declines in honey bees and other native and managed pollinators have led to an increased global dialogue about the potential factors. One important factor is the use of pesticides and the understanding of how plant protection products are affecting this non-target insect group. In contrast to the guidelines already developed for the honey bee Apis mellifera there so far are no test procedures developed for native (non-Apis) bees like solitary bee species, stingless species or other social Non-Apis bees. But these groups of bees are as much as important as pollinators than the honey bee and furthermore, the biology and ecology of non-Apis bees differs from honey bees in several ways.

 

rehberg_project

 

Because of that a ring-test with the objective to validate a method for an acute contact toxicity test of pesticides and other chemicals on solitary bees has been planned and will be conducted at the University Koblenz-Landau with the solitary bee species Osmia bicornis as test species. The study plan was developed at an ICPPR non-Apis workshop and is based on the honeybee contact toxicity test OECD 214 and the method for optimizing laboratory toxicity test for bumblebees. When risk to bees is indicated on the basis of a screening-level (Tier 1) assessment, higher-tier studies with applications to bee-attractive plant materials are an option to refine exposure estimates. Higher tier semi-field scenarios may provide a better opportunity to ensure exposure because the bees would have only the treated crop to forage on for a specified duration. Therefore, the results from a semi-field test potentially provide data for a realistic, worst-case prediction of exposure of limited duration under actual field-use conditions. On this account, a procedure for semi-field studies will be developed as second step of my master thesis. This method development will be performed with the solitary bee species Osmia bicornis as well and once with Sinapis alba, the white mustard, and once with Phacelia tanacetifolia as crop in 4*4,60 m2 big tents. After the field procedure and successful reproduction the brood will be set aside in a climate chamber to analyze their development.

 

Contact Details


Christina Rehberg

Dr. Carsten Brühl