Effects of low oxygen storage on survival of rice weevil and confused flour beetle

Authors: Liu, Yong Biao

Submitted to: Entomological Society of America Annual Meeting
Publication Type: Abstract Only
Publication Acceptance Date: 7/7/2021
Publication Date: 10/30/2021
Citation: Liu, Y.-B. 2021. Effects of low oxygen storage on survival of rice weevil and confused flour beetle. Entomological Society of America Annual Meeting, October 30-November 3, 2021, Denver, Colorado (virtual).

Interpretive Summary:

Technical Abstract: Long-term controlled atmospheres storage with low oxygen levels were evaluated for effects on development and survival of rice weevil and confused flour beetle. Rice weevil eggs and confused flour beetle eggs on pearled barley and wheat flour diet respectively were subjected to 45-day storage under 20.9 (control), 8.0, 6.5, 5.0, and 3.0 % O2 atmospheres at 25°C. All treatments had significant effects on survival of rice weevil and confused flour beetle. The treatments with 5% and 3% O2 resulted in no survival as adults or later life stages for both species. The two species were also exposed to 5% O2 atmosphere for 14 days at egg, larva, and pupa stages to determine relative impact of low oxygen atmosphere storage on different life stages of the insects. After 45 days of development from eggs, rice weevil adults emerged were counted and removed over time and larvae, pupae, and adults of confused flour beetle were collected and scored for mortality. Eggs were more susceptible to the low oxygen storage treatment than larva and pupa and the treatment of eggs resulted no emergence of adults 30 days after the treatment for both species. The low oxygen treatments of larvae and pupae resulted in significant reductions of emergence of rice weevil adults and significant mortality of confused flour beetle larvae and pupae/adults. The results of this study suggest that long term storage under 5% low oxygen atmosphere is effective in controlling rice weevil and confused flour beetle on stored products.