In 2019, wheat and rice combined produced nearly 40 million acres of harvested grain and a production valued of > $11 billion dollars. However, the production of these crops could be higher but grain losses occur throughout the farm-to-fork supply chain. Losses due to grain spillage and pest infestation are two common causes of food loss. Currently, we know that large communities of insects are associated inside and outside food processing and storage facilities. However, we do not know if stored product insects are infesting grain spillage and how fast they infest new grain spillage. The objectives of this research project were to 1) determine what types of insects are present in spillage, 2) determine if insects can colonize fresh spillage, and 3) determine if the use of a grain protectant could inhibit colonization and progeny production of insects infesting spillage. We found that a number of stored product insects, such as the rice weevil and rusty grain beetle, can infest natural grain spillage found around rice milling and storage facilities. We determined that stored product insects can infest fresh spillage in < 48 h and produce progeny. However, the use deltamethrin and cyfluthrin, reduced the number of progeny produced. In summary, sanitation is key to stored product pest management because insects can and will infest grain spillage. However, the use of grain protectants as a top coating on the grain spillage offers some protection of the spilled grain.
