Aphid specific predators in potato in Belgium

Area of Science:

• Entomology
• Agricultural Ecology
• Pest Management

Background:

• Aphid populations in potato fields are influenced by natural predator communities.
• Understanding predator dynamics is crucial for sustainable agriculture and pest control.
• The introduction of non-native species can impact native biodiversity and ecosystem functions.

Purpose of the Study:

• To sample and identify aphid-specific predator populations in Wallonian potato fields.
• To assess the abundance and diversity of ladybirds, hoverflies, and lacewings.
• To document the presence and potential impact of the invasive multicolored Asian beetle (Harmonia axyridis).

Main Methods:

• Predator populations were sampled in four potato fields during summer 2003.
• Methods included visual inspection and beating samples to collect ladybirds, hoverflies, and lacewings.
• Species composition, abundance, and life stages of collected insects were recorded.

Main Results:

• Ladybirds, hoverflies, and lacewings were the most abundant predators, with significant field-to-field variation in composition and abundance.
• Harmonia axyridis, an introduced species, was found in 3 out of 4 fields, indicating adaptation to open-field conditions and potential establishment.
• Native predator populations, including dominant species like Coccinella septempunctata and Episyrphus balteatus, showed varying abundance, with some species potentially underestimated by visual sampling alone.

Conclusions:

• The study confirms the presence of key aphid predators in Belgian potato fields and highlights the successful establishment of Harmonia axyridis.
• The invasive nature and competitive behavior of Harmonia axyridis raise concerns about its future impact on native aphid predator biodiversity.
• Further research is needed to understand the long-term ecological consequences of Harmonia axyridis in agricultural ecosystems.