Paul W. Flinn, flinn@gmprc.ksu.edu, USDA-ARS, Grain Marketing and Production Research Center, 1515 College Ave, Manhattan, KS
Several different types of population suppression methods need to be combined to achieve a low-risk and sustainable management program for stored grain. When used alone, most of these methods, such as aeration, biological control, and sanitation, have only low to moderate effects on suppressing population growth of stored grain insects. However, when these methods are combined they can have synergistic effects that can result in high levels of population suppression. Studies with the lesser grain borer, Rhyzopertha dominica, showed that the parasitic hymenoptera that parasitizes this beetle was ten times more effective when the grain was cooled with aeration from 32ºC to 25ºC. These hymenoptera parasitoids frequently occur naturally in stored grain. Grain sampling can determine if natural enemies are present, or if the storage would benefit from augmentative releases. There are many factors that impact the success of a biological control program, such as releasing the appropriate species, number of parasitoids to release, and timing the releases to coincide with the susceptible host stage. Host parasitoid models can provide important information on many of these parameters in practical biological control programs. The overlying strategy for a low-risk control program is prevention. Methods need to be selected that will limit the pest insect’s ability to develop and reproduce in the grain. In addition, these methods need to be neutral, or favor the growth and development of natural enemies. Ideally, you never want to progress to a situation in which you have to resort to fumigation.
Species 1: Coleoptera Bostrichidae
Rhyzopertha dominicaSpecies 2: Coleoptera Laemophloeidae
Cryptolestes ferrugineusKeywords: Stored products, IPM
Recorded presentation