Abstract
The aim of this study was to investigate the effects of Elado® (10 g clothianidin & 2 g beta-cyfluthrin/kg seed)-dressed oilseed rape on the development and reproduction of mason bees (Osmia bicornis) as part of a large-scale monitoring field study in Northern Germany, where oilseed rape is usually cultivated at 25–33 % of the arable land. Both reference and test sites comprised 65 km2 in which no other crops attractive to pollinating insects were present. Six study locations were selected per site and three nesting shelters were placed at each location. Of these locations, three locations were directly adjacent to oilseed rape fields, while the other three locations were situated 100 m distant from the nearest oilseed rape field. At each location, 1500 cocoons of O. bicornis were placed into the central nesting shelter. During the exposure phase, nest building activities and foraging behaviour were assessed repeatedly. Cocoons were harvested in autumn to assess parasitization and reproduction including larval development. The following spring, the emergence of the next generation of adults from cocoons was monitored. High reproductive output and low parasitization rates indicated that Elado®-dressed oilseed rape did not cause any detrimental effects on the development or reproduction of mason bees.
Highlights
Pollination is one of the most essential ecosystem services provided by nature to wild plant species, and for a number of arable crops (Klein et al 2007)
Emergence of O. bicornis started soon after the cocoons were placed in the field: The first males emerged from the cocoons as early as DAP 0 at all study locations, followed by the first females on DAP 3
Poisson lognormal Generalized additive mixed models (GAMMs) were used to model the relationship between the number of nesting females and other covariables including the DAP, distance to oilseed rape (OSR) fields, rotation of nesting block and weather covariables
Summary
Pollination is one of the most essential ecosystem services provided by nature to wild plant species, and for a number of arable crops (Klein et al 2007). Solitary bees are able to provide pollination services in certain crops with similar or sometimes superior level of efficiency (Bosch et al 2006). In this regard, it has been shown that they can replace honey bees (Winfree et al 2007) or act synergistically with them (Garibaldi et al 2013; Brittain et al 2013). As one of the factors responsible for the observed decline the intensification of agriculture was identified, which might endanger pollination services (Goulson et al 2015)
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
