ARS | Publication request: Directional flow of aeration to manage insect pests in stored wheat

Submitted to: Insight
Publication Type: Other
Publication Acceptance Date: May 24, 2011
Publication Date: N/A

Technical Abstract: Using low-volume ambient air to cool stored grain is a common management practice in the southern plains, but little research has been done recently to determine if the direction of airflow makes a difference regarding the cooling and insect pest populations. We conducted a study by using suction aeration, pulling air downward through the grain mass, as compared to pressure aeration, the standard strategy of pushing cool air upward through the grain mass. Results of a two-year study showed that temperatures on the upper surface of the grain mass were consistently cooler with suction aeration than with pressure aeration. The resulting insect pest populations were also generally lower in the bins with suction versus pressure aeration. Our results indicated that using suction aeration would cool the upper surface zone of the grain mass, which is vulnerable to insect infestation, and could reduce the need for additional pesticide inputs through this reduction in pest pressure. Based on these results, a new study has been initiated to examine temperature gradients in the headspace zone of wheat storage bins with pressure versus suction aeration, and to determine the extent of the interactions between the headspace temperatures and those in the upper surface zone of the bulk grain mass.