Survival of Immature Rusty Grain Beetles (Coleoptera: Cucujidae) on Various Particle Sizes of Cracked Corn²

Survival of individually-reared immature rusty grain beetles (RGB), Cryptolestes ferrugineus (Stephens), was determined on finely cracked, medium cracked, and coarsely cracked corn maintained at 30°C and 75% RH. The study was conducted to determine whether differences in progeny production on the various particle sizes of corn (as shown in an earlier study) could be attributed to inherent differences among the various particle sizes of cracked corn in their ability to support egg to adult development of RGB. The proportion of the test population surviving (number of live adults/number of eggs hatched) was 0.76 (214/280) for finely cracked corn, 0.79 (222/280) for medium cracked corn, and 0.72 (194/269) for coarsely cracked corn. These differences in survival were not statistically significant. Thus, the hypothesis that there are differences in inherent suitability of the various particle sizes of cracked corn for supporting egg to adult development of RGB is not supported.