Modeling of Sitophilus oryzae (L.) (Coleoptera: Curculionidae) based on historical weather data indicates aeration is effective for management of wheat stored in Greece

Abstract

An in-silico study was conducted to determine the feasibility of using aeration to manage Sitophilus oryzae (L.) in stored wheat throughout the country of Greece. Daily high and low temperature data were obtained for sixteen representative sites from 2010 to 2019 and averaged to predict hours below aeration temperature thresholds of 15, 18, and 21 °C from August–November. The sixteen sites were classified into distinct aeration zones based on temperature, which was associated with differences in latitude and elevation. In-silico predictions were developed for S. oryzae population growth in unaerated wheat, wheat aerated starting 15 July, and wheat aerated based on aeration triggering temperatures of 15, 18, and 21 °C. The optimal scenarios for inhibition of S. oryzae growth in wheat stored in the warmest Zone 1 is aeration triggered at 21 °C, but fumigations may be required in this zone. Aeration starting 15 July at 15 °C or aeration at 18 and 21 °C provides the best suppression of population growth for wheat stored in Zone 2, an intermediate climatic zone. For the coolest Zone 3, any aeration scenario is equally effective in suppressing S. oryzae. For all zones, predicted S. oryzae populations in unaerated wheat increase exponentially in late autumn to catastrophic levels, far exceeding the generally accepted level of 2 live adults per kg of wheat for export. The results presented herein can be used to develop aeration-based wheat management in Greece and may possibly lead to reduced reliance on fumigants for control of S. oryzae.