Sitophilus zeamais (Coleoptera: Curculionidae) Activity and Germination of Corn Seeds Stored under Vacuum Pressure

Warehouse pests cause losses in seed quality by physically damaging seeds, carrying other pathogens, and leaving residues of their consumption or their remains. Taking into account that warehouse pests have higher metabolism rates than seeds, in the present study, the viability of Sitophilus zeamais (Motschulsky & V.de, 1855) insects and the germination of corn seeds were evaluated for 93 and 180 days, respectively, under conditions of a partial vacuum (0.26 atm (atmosphere)), hermetic sealing, and air exchange. The partial vacuum environment (0.26 atm) did not negatively affect the germination of the seeds over a period of 180 days and resulted in the mortality of adult insects from the 4th day onwards; it also completely prevented physical damage to the seeds. The hermetic packaging did not negatively affect germination, but the insects remained active until day 34, and there was severe damage to the seeds used for their sustenance. Similarly, the gas exchange packaging did not affect germination, but the insects remained active until the last day of observation (93) and also caused severe damage to the seeds used for their maintenance. Partial vacuum (0.26 atm) storage represents a practical solution in certain conditions, for example, the short-term (6 months) storage of germplasms at room temperature (24–26 °C); it can also be useful in the storage and transfer of grains, with the possibility of eliminating or reducing the need for insecticide applications.