Seasonal, Landscape, and Attractant Effects on Lesser Grain Borer, Rhyzopertha dominica (F.), Captures in Northeast Kansas

Authors: Scheff, Deanna; Campbell, James - Jim; Arthur, Franklin

Submitted to: Agronomy Journal
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/24/2021
Publication Date: 12/31/2021
Citation: Scheff, D.S., Campbell, J.F., Arthur, F.H. 2021. Seasonal, Landscape, and Attractant Effects on Lesser Grain Borer, Rhyzopertha dominica (F.), Captures in Northeast Kansas. Agronomy Journal. 12(1)99:3-17. https://doi.org/10.3390/agronomy12010099.
DOI: https://doi.org/10.3390/agronomy12010099

Interpretive Summary: The lesser grain borer, Rhyzopertha dominica, is a serious pest of stored grain, but can also be found in diverse environments far from stored grain. Our objectives were to (1) observe the seasonal patterns of lesser grain borer captures near a feed mill, grain storage elevator, and in a natural tallgrass prairie and (2) evaluate different combinations of wheat and pheromone as attractants in traps. The lesser grain borer was captured in traps baited with wheat and pheromone combinations in all locations using Lindgren funnel traps. The tallgrass prairie had the most captures in 2017, and the grain elevator the most in 2018. There was a positive relationship between beetle captures and temperatures whereby warmer temperatures increased the number of beetles captured. In traps without a pheromone, there were more beetles captured using previously feed on wheat compared to high moisture or crimped wheat. The addition of a pheromone lure, increased trap captures. The trap containing a pheromone and crimped wheat had the highest number of beetles captured among all attractants tested. Beetles were captured at all locations in 2017 and 2018, which indicates their presence in these landscapes exist year-to-year. Actively trapping or monitoring around these type of field sites for lesser grain borer presence and changes in captures, is one tool to help identify when population levels are changing, and grain managers may need to make a pest management decision to protect their product. Continual monitoring at specific locations can predict when peak flight of lesser grain borer adults occurs throughout a year, and when additional pest management tactics need to be employed.

Technical Abstract: The lesser grain borer, Rhyzopertha dominica (F.), is a highly diverse feeder and widely distributed throughout the United States in agricultural and non-agricultural landscapes. Six, four-funnel Lindgren traps were deployed in feed mill, grain elevator, and native prairie landscapes, to determine the most attractive food and pheromone combination (attractant) and patterns in seasonal captures. Traps were baited with combinations of wheat (crimped, high moisture, pre-fed) with or without a R. dominica specific aggregate pheromone in 2017 and 2018. Traps were deployed for 48 h, collected, and the number of R. dominica counted. Rhyzopertha dominica was captured among all landscapes with all attractants. There was a significant correlation between temperature and R. dominica captures, and peak captures occurring during the warmest months. Significantly more R. dominica adults were captured in traps containing the pheromone. In 2017, pheromone traps captured 818% more R. dominica and 543% more in 2018. The pheromone component in the trap was more attractive than any natural stored wheat condition and should be included in future studies. Understanding the seasonal patterns and changes in capture rates in agricultural and non-agricultural landscapes, may be useful in determining times of increased immigration pressure into new locations of stored grain.