The objective of this study was to determine the shortest time of fumigation to promote the total mortality of adult insects of the genus Sitophilus, in grains of wheat, undergoing fumigation in chamber of tarpaulin. The experiment was carried out in a grain storage unit in Ponta Grossa - PR. The experimental design was completely randomized, with six treatments and ten replications. Treatments consisted of times of exposure of wheat grain fumigation: zero; 12; 36; 60; 84 and 108 hours, in bucket trucks wrapped in tarpaulin (forming the chambers of tarpaulin). It was applied the commercial product Fertox(r) in tablets form, with the dosage of 6g m-³ in each chamber of 35m³. Repetitions were composed by cages with ten live adult insects of the Sitophilus genus each one, inserted into the grain mass in bucket trucks and arranged at various points and depths. The fitted regression model to describe the insect mortality behavior (M) according to the fumigation time (T) was M=6.6867+93.4694 (1-e0.1645T)26.9607. Equation shows that 58.9h after application of the steam product the insect mortality is of 100%.
bucket truck; Sitophilus; fumigation period