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Two models of grain temperatures and insect populations in stored wheat

Mani, S., Flinn, P.W., Muir, W.E., Jayas, D.S., White, N.D.G.
Transactions of the ASAE 2001 v.44 no.3 pp. 655
Cryptolestes ferrugineus, population dynamics, temperature, stored products, mathematical models, grains
Stored grain temperatures and population dynamics of rusty grain beetles, Cryptolestes ferrugineus (Stephens), predicted by a hot spot model, which included feedback from the insect model to the temperature model, and a spatial model, which did not include that feedback, were compared. For an initial grain temperature of 30 degrees C and an initial population of 10,000 adult insects in stored grain at Winnipeg, Canada, the hot spot model predicted a maximum of 120 adults/kg of wheat at the center of the grain bulk toward the end of fall and a maximum temperature of 39 degrees C. The spatial model predicted an adult population of 500 adults/kg of wheat and no increases in temperatures. For the same simulation conditions but using weather data for Topeka, Kansas, the hot spot model predicted a maximum of 150 adults/kg of wheat at the center of the bulk in fall, while the spatial model predicted a maximum of 800 adults/kg. The hot spot model is closer to reality than the spatial model because it simulates the effects of variable heating around the bin wall, insect heat production, and insect movement.