Sawtooth grain beetle, Oryzaephilus surinamensis, an internationally important stored product pest

Authors: GOURGOUTA, MARINA - University Of Thessaly; Morrison, William - Rob; HAGSTRUM, DAVID - Kansas State University; ATHANASSIOU, CHRISTOS - University Of Thessaly

Submitted to: Journal of Stored Products Research
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 7/22/2023
Publication Date: 10/11/2023
Citation: Gourgouta, M., Morrison III, W.R., Hagstrum, D.W., Athanassiou, C. 2023. Sawtooth grain beetle, Oryzaephilus surinamensis, an internationally important stored product pest. Journal of Stored Products Research. 104. Atricle 102165. https://doi.org/10.1016/j.jspr.2023.102165.
DOI: https://doi.org/10.1016/j.jspr.2023.102165

Interpretive Summary: The saw-toothed grain beetle is a major pest of many stored products worldwide that feeds on the exterior portion of grain. The last review on the general biology, ecology, distribution, and pest management of this species was performed almost a decade ago, thus we provide an up-to-date review on these topics with an emphasis on knowledge gaps that need to be addressed to improve management of this species. This insect can feed and reproduce on at least 31 suitable foods and has been found in 104 countries and 21 types of facilities, including in at least 48%, 54%, 43%, 48%, and 50% of the countries in Africa, Asia, Europe, North America, and Oceania. Females can lay up to 300-400 eggs in their lifetime at rate of 6-10 per day. Production of offspring is highest at 30–32.5°C and 30–70% relative humidity and tapers off at lower and higher temperatures. The average lifespan of adults can reach 19 weeks. Although adults have well-developed wings, flight has rarely been observed. Further, saw-toothed grain beetle has a male-produced aggregation pheromone attractive to both sexes consisting of three different volatiles that can be deployed in traps to monitor population levels. Although seventy-six studies have been published on the efficacy of 54 insecticides for grain beetle, only chlorpyrifos-methyl, fenitrothion, malathion and pirimiphos-methyl were included in more than seven studies. A considerable number of recent studies have shown that resistance to numerous insecticides is increasing in this species. However, research on non-chemical control of this species should also be expanded, including the use of cold and heat treatments, pheromones to manipulate populations, as well as the application of carbon dioxide or nitrogen. Models predicting insect population growth can improve pest management decisions. This work provides insight into research questions that must be addressed to develop sustainable pest management strategies for the saw-toothed grain beetle well into the next decade.

Technical Abstract: The saw-toothed grain beetle is a major pest of many stored products worldwide that feeds on the exterior portion of grain. The last review on the general biology, ecology, distribution, and pest management of this species was performed almost a decade ago, thus we provide an up-to-date review on these topics with an emphasis on knowledge gaps that need to be addressed to improve management of this species. This insect can feed and reproduce on at least 31 suitable foods and has been found in 104 countries and 21 types of facilities, including in at least 48%, 54%, 43%, 48%, and 50% of the countries in Africa, Asia, Europe, North America, and Oceania. Females can lay up to 300-400 eggs in their lifetime at rate of 6-10 per day. Production of offspring is highest at 30–32.5°C and 30–70% relative humidity and tapers off at lower and higher temperatures. The average lifespan of adults can reach 19 weeks. Although adults have well-developed wings, flight has rarely been observed. Further, saw-toothed grain beetle has a male-produced aggregation pheromone attractive to both sexes consisting of three different volatiles that can be deployed in traps to monitor population levels. Although seventy-six studies have been published on the efficacy of 54 insecticides for grain beetle, only chlorpyrifos-methyl, fenitrothion, malathion and pirimiphos-methyl were included in more than seven studies. A considerable number of recent studies have shown that resistance to numerous insecticides is increasing in this species. However, research on non-chemical control of this species should also be expanded, including the use of cold and heat treatments, pheromones to manipulate populations, as well as the application of carbon dioxide or nitrogen. Models predicting insect population growth can improve pest management decisions. This work provides insight into research questions that must be addressed to develop sustainable pest management strategies for the saw-toothed grain beetle well into the next decade.