Survey of Soybean Insect Pollinators: Community Identification and Sampling Method Analysis

Area of Science:

• Entomology
• Ecology
• Agriculture

Background:

• Soybean (Glycine max) flowers provide nectar and pollen for various pollinators, including honey bees, wild bees, and flies.
• Understanding soybean's pollinator community is vital for crop yield and ecosystem health.

Purpose of the Study:

• To characterize the pollinator community in Iowa soybean fields.
• To evaluate the effectiveness of different sampling methods (bee bowls, yellow sticky traps, sweep nets) for pollinator assessment.
• To determine if key bee species collect soybean pollen.

Main Methods:

• Pollinators were trapped using modified pan traps (bee bowls), yellow sticky traps, and sweep nets in Iowa soybean fields during the R1-R6 reproductive stages in 2011 and 2012.
• Collected specimens were identified to species level.
• Pollen loads on captured bees were examined for the presence of soybean pollen.

Main Results:

• A total of 5,368 individuals from at least 50 species were collected across all methods.
• Bee bowls captured the highest number of individuals (3,644) and species (44), indicating superior efficacy.
• Soybean pollen was found on 29% (2011) and 38% (2012) of examined bees with pollen loads, confirming foraging activity.

Conclusions:

• Iowa soybean fields support a diverse pollinator community, dominated by native solitary bees.
• Modified bee bowls are the recommended method for effectively sampling soybean field pollinators.
• Native bees actively forage on soybean flowers, contributing to pollination services.