TY - JOUR

T1 - Do natural enemies really make a difference?

T2 - field scale impacts of parasitoid wasps and hoverfly larvae on cereal aphid populations

AU - Ramsden, Mark

AU - Menendez Martinez, Maria Rosa

AU - Leather, Simon

AU - Wackers, Felix Leopold

N1 - This is the peer reviewed version of the following article: Ramsden, M., Menendez, R., Leather, S. and Wäckers, F. (2017), Do natural enemies really make a difference? Field scale impacts of parasitoid wasps and hoverfly larvae on cereal aphid populations. Agr Forest Entomol, 19: 139–145. doi:10.1111/afe.12191 which has been published in final form at http://onlinelibrary.wiley.com/doi/10.1111/afe.12191/abstract This article may be used for non-commercial purposes in accordance With Wiley Terms and Conditions for self-archiving.

PY - 2017/5

Y1 - 2017/5

N2 - 1. Naturally occurring predators and parasitoids are known to reduce the abundance of pest invertebrates in arable crops, yet current treatment thresholds do not account for this contribution to pest management. 2. Here, we provide evidence for the presence of natural enemies correlating with a subsequent reduction in pest population growth. 3. The abundance of cereal aphid pests and two key aphidophagous natural enemies, parasitoid wasps (Aphidiinae) and hoverfly larvae (Syrphinae) were assessed at field boundaries and interiors in southeast England. 4. The highest rate of aphid population growth was associated with locations where no natural enemies were found. The presence of either Aphidiinae wasps or predatory Syrphinae larvae was associated with a reduction in the rate of aphid population growth irrespective of location within the field, and overall aphid population growth was negatively correlated with increasing natural enemy abundance. 5. This work indicates that natural enemies contribute significantly to pest control, and provides further evidence in support of using management strategies to promote their occurrence in agro-ecosystems. 6. Aphid predators and parasitoids make an important contribution to aphid pest control within cereal fields, and thresholds for insecticide application should account for this to avoid unnecessary treatments.

AB - 1. Naturally occurring predators and parasitoids are known to reduce the abundance of pest invertebrates in arable crops, yet current treatment thresholds do not account for this contribution to pest management. 2. Here, we provide evidence for the presence of natural enemies correlating with a subsequent reduction in pest population growth. 3. The abundance of cereal aphid pests and two key aphidophagous natural enemies, parasitoid wasps (Aphidiinae) and hoverfly larvae (Syrphinae) were assessed at field boundaries and interiors in southeast England. 4. The highest rate of aphid population growth was associated with locations where no natural enemies were found. The presence of either Aphidiinae wasps or predatory Syrphinae larvae was associated with a reduction in the rate of aphid population growth irrespective of location within the field, and overall aphid population growth was negatively correlated with increasing natural enemy abundance. 5. This work indicates that natural enemies contribute significantly to pest control, and provides further evidence in support of using management strategies to promote their occurrence in agro-ecosystems. 6. Aphid predators and parasitoids make an important contribution to aphid pest control within cereal fields, and thresholds for insecticide application should account for this to avoid unnecessary treatments.

U2 - 10.1111/afe.12191

DO - 10.1111/afe.12191

M3 - Journal article

VL - 19

SP - 139

EP - 145

JO - Agricultural and Forest Entomology

JF - Agricultural and Forest Entomology

SN - 1461-9555

IS - 2

ER -