Potential surrogate plants for use in semi-field pesticide risk assessment with Megachile rotundata
Background Current regulatory pesticide risk assessments for bees are based primarily on the honey bee (Apis mellifera) and may not always be protective of solitary bees. To incorporate solitary bees into the risk assessment process, standardized methods to assess the hazard of pesticides under semi...
| Main Authors: | , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
PeerJ Inc.
2019-01-01
|
| Series: | PeerJ |
| Subjects: | |
| Online Access: | https://peerj.com/articles/6278.pdf |
| _version_ | 1797418544139337728 |
|---|---|
| author | Andrew J. Frewin Angela E. Gradish Graham R. Ansell Cynthia D. Scott-Dupree |
| author_facet | Andrew J. Frewin Angela E. Gradish Graham R. Ansell Cynthia D. Scott-Dupree |
| author_sort | Andrew J. Frewin |
| collection | DOAJ |
| description | Background Current regulatory pesticide risk assessments for bees are based primarily on the honey bee (Apis mellifera) and may not always be protective of solitary bees. To incorporate solitary bees into the risk assessment process, standardized methods to assess the hazard of pesticides under semi-field (Tier II) conditions will be needed. We conducted a series of experiments over 2 years to assess potential surrogate plants and adult release rates for use in semi-field experiments with the alfalfa leafcutting bee (ALB, Megachile rotundata). Methods We compared ALB foraging activity and reproduction on 12 m2 plots of flowering alfalfa (Medicago sativa) and buckwheat (Fagopyrum esculentum) at low (10♀/20♂) and high (20♀/40♂) adult release rates. The following year, we assessed the same endpoints on plots of purple tansy (Phacelia tanacetifolia) at a release rate of 10♀/15♂. Results Although ALB foraging activity was high on buckwheat plots, fewer adults were produced compared to alfalfa plots. On alfalfa, there were no differences in foraging activity, nesting, or reproduction between the low and high release rates. ALB readily foraged from purple tansy flowers, but females avoided purple tansy leaves for leaf cell construction. Discussion Our study suggests that buckwheat alone cannot support ALB during semi-field studies on small plots. For alfalfa, we recommend a maximum release rate of 10♀/20♂ in 12 m2 plots. Further study of higher ALB release rates on purple tansy is warranted. A mixed planting of purple tansy and a plant suitable for leaf piece collection (e.g., buckwheat) may provide favorable conditions for ALB activity and reproduction during semi-field testing. |
| first_indexed | 2024-03-09T06:34:24Z |
| format | Article |
| id | doaj.art-9f5045ed58644f72865d68ca9d53c062 |
| institution | Directory Open Access Journal |
| issn | 2167-8359 |
| language | English |
| last_indexed | 2024-03-09T06:34:24Z |
| publishDate | 2019-01-01 |
| publisher | PeerJ Inc. |
| record_format | Article |
| series | PeerJ |
| spelling | doaj.art-9f5045ed58644f72865d68ca9d53c0622023-12-03T11:00:32ZengPeerJ Inc.PeerJ2167-83592019-01-016e627810.7717/peerj.6278Potential surrogate plants for use in semi-field pesticide risk assessment with Megachile rotundataAndrew J. Frewin0Angela E. Gradish1Graham R. Ansell2Cynthia D. Scott-Dupree3School of Environmental Sciences, University of Guelph, Guelph, Ontario, CanadaSchool of Environmental Sciences, University of Guelph, Guelph, Ontario, CanadaSchool of Environmental Sciences, University of Guelph, Guelph, Ontario, CanadaSchool of Environmental Sciences, University of Guelph, Guelph, Ontario, CanadaBackground Current regulatory pesticide risk assessments for bees are based primarily on the honey bee (Apis mellifera) and may not always be protective of solitary bees. To incorporate solitary bees into the risk assessment process, standardized methods to assess the hazard of pesticides under semi-field (Tier II) conditions will be needed. We conducted a series of experiments over 2 years to assess potential surrogate plants and adult release rates for use in semi-field experiments with the alfalfa leafcutting bee (ALB, Megachile rotundata). Methods We compared ALB foraging activity and reproduction on 12 m2 plots of flowering alfalfa (Medicago sativa) and buckwheat (Fagopyrum esculentum) at low (10♀/20♂) and high (20♀/40♂) adult release rates. The following year, we assessed the same endpoints on plots of purple tansy (Phacelia tanacetifolia) at a release rate of 10♀/15♂. Results Although ALB foraging activity was high on buckwheat plots, fewer adults were produced compared to alfalfa plots. On alfalfa, there were no differences in foraging activity, nesting, or reproduction between the low and high release rates. ALB readily foraged from purple tansy flowers, but females avoided purple tansy leaves for leaf cell construction. Discussion Our study suggests that buckwheat alone cannot support ALB during semi-field studies on small plots. For alfalfa, we recommend a maximum release rate of 10♀/20♂ in 12 m2 plots. Further study of higher ALB release rates on purple tansy is warranted. A mixed planting of purple tansy and a plant suitable for leaf piece collection (e.g., buckwheat) may provide favorable conditions for ALB activity and reproduction during semi-field testing.https://peerj.com/articles/6278.pdfSemi-fieldRisk assessmentNon-apisSolitary bee |
| spellingShingle | Andrew J. Frewin Angela E. Gradish Graham R. Ansell Cynthia D. Scott-Dupree Potential surrogate plants for use in semi-field pesticide risk assessment with Megachile rotundata PeerJ Semi-field Risk assessment Non-apis Solitary bee |
| title | Potential surrogate plants for use in semi-field pesticide risk assessment with Megachile rotundata |
| title_full | Potential surrogate plants for use in semi-field pesticide risk assessment with Megachile rotundata |
| title_fullStr | Potential surrogate plants for use in semi-field pesticide risk assessment with Megachile rotundata |
| title_full_unstemmed | Potential surrogate plants for use in semi-field pesticide risk assessment with Megachile rotundata |
| title_short | Potential surrogate plants for use in semi-field pesticide risk assessment with Megachile rotundata |
| title_sort | potential surrogate plants for use in semi field pesticide risk assessment with megachile rotundata |
| topic | Semi-field Risk assessment Non-apis Solitary bee |
| url | https://peerj.com/articles/6278.pdf |
| work_keys_str_mv | AT andrewjfrewin potentialsurrogateplantsforuseinsemifieldpesticideriskassessmentwithmegachilerotundata AT angelaegradish potentialsurrogateplantsforuseinsemifieldpesticideriskassessmentwithmegachilerotundata AT grahamransell potentialsurrogateplantsforuseinsemifieldpesticideriskassessmentwithmegachilerotundata AT cynthiadscottdupree potentialsurrogateplantsforuseinsemifieldpesticideriskassessmentwithmegachilerotundata |