Maize samples were collected at the start of the experiment (zero time) and after 3 months of storage. After the storage period, grain in each bag was retrieved by hand and sieved through a 3/16 inch (4.76 mm) round-hole sieve. The material passing through the sieve was stored at −20° C until insects were analyzed. At the same time, grain samples (750 g) were collected from the top, middle and bottom regions of each bag. Moisture content of the maize was determined in triplicate for the top, middle, and bottom of each bag by dry weight methods according to ASABE standards (Standard, 2012).