Monarch Butterfly Utilization of Milkweed Plants Grown in Close Proximity to Corn Treated by a Neonicotinoid Insecticide (Seed Treatment) Active
Monarch butterfly populations have declined sufficiently to result in noticeably fewer overwintering at sites in central Mexico as in California.
The Science Issue and Relevance: Monarch butterfly populations have declined sufficiently to result in noticeably fewer overwintering at sites in central Mexico as in California. The causes for the reduced population are not fully known, but may include loss of overwintering habitat and reproduction habitat. In the latter instance, increased herbicide (i.e. glyphosate) use in the Midwestern U.S. is blamed for a drastic decline of milkweed, which is the host plant for the Monarch butterfly. Numerous conservation efforts are underway to increase habitats favorable for monarch reproduction, which should include increased milkweed colonies available for the butterflies. The uncertainty is whether or not monarch reproduction on milkweed in close proximity to fields treated with neonicitinoid insecticides would be successful.
Seed coating with pesticides is believed to be one of the more environmentally friendly methods of crop treatment.Upon germination, the pesticide is absorbed by the roots (systemic insecticide) and distributes throughout the plant. When the plant is consumed by a pest insect, they ingest and may be affected by the insecticide. Unfortunately, some of the insecticide is leached away from the seed into the groundwater and adjacent water ways. When this occurs, the insecticide is available for uptake by other plants resulting in their detection in other herbivorous insects, which could be negatively affected.
Methodology for Addressing the Issue: A controlled exposure study is being conducted to evaluate the impact of neonicotinoid insecticides upon monarch utilization of milkweed plants. Milkweed plants are being grown in close proximity to corn plants germinated from treated and untreated seed, presuming that those plants will absorb the insecticide that leaches from the seed. Use of the milkweed plants by monarch butterflies, as well as other herbivorous insects, will be quantified to address the hypothesis that insecticides on treated seed affect insects on adjacent plants.
Future Steps: We plan to expand this project to include a granular neonicotinoid insecticide product. The granular product is used to control herbivorous insects in residential landscapes. This aspect of the study will generate a dose response relationship between the granular product and effect upon monarch utilization of milkweed plants.
Below are other science projects associated with this project.
Effect of Chronic Neonicotinoid Insecticide Exposure upon Monarch Development
- Overview
Monarch butterfly populations have declined sufficiently to result in noticeably fewer overwintering at sites in central Mexico as in California.
Sources/Usage: Some content may have restrictions. View Media DetailsMonarch butterflies are in decline The Science Issue and Relevance: Monarch butterfly populations have declined sufficiently to result in noticeably fewer overwintering at sites in central Mexico as in California. The causes for the reduced population are not fully known, but may include loss of overwintering habitat and reproduction habitat. In the latter instance, increased herbicide (i.e. glyphosate) use in the Midwestern U.S. is blamed for a drastic decline of milkweed, which is the host plant for the Monarch butterfly. Numerous conservation efforts are underway to increase habitats favorable for monarch reproduction, which should include increased milkweed colonies available for the butterflies. The uncertainty is whether or not monarch reproduction on milkweed in close proximity to fields treated with neonicitinoid insecticides would be successful.
Sources/Usage: Some content may have restrictions. View Media DetailsMonarch larva on milkweed Seed coating with pesticides is believed to be one of the more environmentally friendly methods of crop treatment.Upon germination, the pesticide is absorbed by the roots (systemic insecticide) and distributes throughout the plant. When the plant is consumed by a pest insect, they ingest and may be affected by the insecticide. Unfortunately, some of the insecticide is leached away from the seed into the groundwater and adjacent water ways. When this occurs, the insecticide is available for uptake by other plants resulting in their detection in other herbivorous insects, which could be negatively affected.
Methodology for Addressing the Issue: A controlled exposure study is being conducted to evaluate the impact of neonicotinoid insecticides upon monarch utilization of milkweed plants. Milkweed plants are being grown in close proximity to corn plants germinated from treated and untreated seed, presuming that those plants will absorb the insecticide that leaches from the seed. Use of the milkweed plants by monarch butterflies, as well as other herbivorous insects, will be quantified to address the hypothesis that insecticides on treated seed affect insects on adjacent plants.
Sources/Usage: Some content may have restrictions. View Media DetailsMilkweed plants in the controlled exposure study Future Steps: We plan to expand this project to include a granular neonicotinoid insecticide product. The granular product is used to control herbivorous insects in residential landscapes. This aspect of the study will generate a dose response relationship between the granular product and effect upon monarch utilization of milkweed plants.
- Science
Below are other science projects associated with this project.
Effect of Chronic Neonicotinoid Insecticide Exposure upon Monarch Development
The long-term viability of monarch butterfly ( Danaus plexippus ) populations in North America is in doubt.