Feasibility of using aeration to cool wheat stored in Slovenia: A predictive modeling approach using historical weather data

Authors: Arthur, Franklin; Morrison, William - Rob; TRDAN, STANE - University Of Ljubljana

Submitted to: Applied Sciences
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/27/2020
Publication Date: 9/1/2020
Citation: Arthur, F.H., Morrison III, W.R., Trdan, S. 2020. Feasibility of using aeration to cool wheat stored in Slovenia: A predictive modeling approach using historical weather data. Applied Sciences. 10(17):6066. https://doi.org/10.3390/app10176066.
DOI: https://doi.org/10.3390/app10176066

Interpretive Summary: Wheat is an important crop in the Balkan region of Europe, including the country of Slovenia, but there has been little recent research concerning management of wheat stored in bins an silos. Aeration, which involves the use of low-volume ambient air to cool store wheat, is an important component of management plans for wheat stored in the USA. A study was conducted using historical weather data from 10 sites in Slovenia to determine the potential for use of aeration to cool stored wheat and limit population growth of the rice weevil, a major pest of stored wheat. Using a start date of August 1, sufficient hours of temperatures below 60 °F , were available in August and September to cool wheat throughout the country, including the warm coastal area. A degree-day model also showed that in the absence of aeration, a new generation of rice weevils could be completed after the start date of August 1 in some of the sites. Three selected sites were then analyzed using a bin-cooling model coupled with a rice weevil population model developed by Texas A&M Beaumont, and results showed the dramatic reduction in insect population development that could be achieved using aeration. Results show a tremendous potential for inclusion of aeration into management programs, and reducing reliance on phosphine fumigation for insect control, thus alleviation concerns regarding world-wide development of phosphine resistance in stored product insects.

Technical Abstract: The use of aeration, which refers to cooling of a grain mass using low-volume airflow rates with ambient air, is an under-utilized component of management programs. A model simulation study was conducted for the country of Slovenia by examining historical weather data for 10 selected sites to determine if sufficient cooling hours < 15°C were available in August and September to cool stored wheat. The weather data were then coupled with a degree-day model to determine if a generation of Sitophilus oryzae (L.), the rice weevil, could be produced in the absence of aeration, using a start date of 1 August. The weather data for September was used to classify Slovenia into different risk zones, depending on the number hours < 15°C. Three sites from each zone, from warmest to coolest, Portorož, Novo Mesto, and Lesce, were further examined using a web-based aeration model and insect population growth model for S. oryzae developed by Texas A&M University Beaumont TX for cooling stored rough rice to predict bin temperatures and population growth from 1 August to 30 November. Results showed that for most of Slovenia, in the absence of aeration, a complete generation of S. oryzae could occur based on an infestation beginning 1 August. The use of aeration immediately cooled stored wheat in the three selected sites, resulting in a dramatic decrease in predicted populations of S. oryzae in aerated wheat compared to unaerated wheat. Results show that the use of aeration may be expanded in Slovenia for management of stored commodities, and could help alleviate dependence on insecticides for insect pest management after harvest.