Comparison of Two Sampling Methods for Assessing Halyomorpha halys (Hemiptera: Pentatomidae) Numbers in Soybean...

Area of Science:

• Agricultural Entomology
• Pest Management
• Soybean Production

Background:

• The brown marmorated stink bug (Halyomorpha halys) poses a significant challenge for soybean pest monitoring.
• Its characteristic "startle response" complicates traditional sampling methods like sweep nets.
• Effective population assessment is crucial for timely and accurate pest management decisions.

Purpose of the Study:

• To evaluate the efficacy of a visual plant inspection method for sampling the brown marmorated stink bug in soybean fields.
• To compare the visual inspection method with traditional sweep net sampling.
• To establish a relationship between visual counts and established economic thresholds.

Main Methods:

• A 2-minute visual inspection of soybean plants was conducted while walking between rows.
• A 30-minute interval allowed for stink bug repositioning before resampling.
• The area was then sampled using 15 sweeps with a 38-cm-diameter sweep net.
• Data from 76 fields and 2,042 paired comparisons were analyzed.

Main Results:

• A strong linear relationship was found between visual counts and sweep net samples (R² = 0.6934).
• An average visual count of 5.4 brown marmorated stink bugs in 2 minutes correlated with the economic threshold of 5 bugs per 15 sweeps.
• The visual inspection method demonstrated effectiveness in assessing pest populations.

Conclusions:

• Visual plant inspection is a viable and effective alternative for monitoring brown marmorated stink bug populations in soybeans.
• This method can aid in making informed pest management decisions.
• Further adoption of visual inspection can improve sampling efficiency and accuracy.