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The fall armyworm, Spodoptera frugiperda (J.E. Smith), is a global pest that feeds on  > 350 plant species and causes major yield loses. Variation in the responses of S. frugiperda males to female sex pheromone compounds affects the detection, monitoring and management of the pest. We determined geographic variation in the responses of S. frugiperda males to four different doses of synthetic sex pheromone compounds using a gas chromatography-electroantennogram detector (GC-EAD). Furthermore, we disentangled regional populations into C- and R- mitotypes via molecular analysis of the cytochrome oxidase I gene, and measured their responses to the compounds. When comparing responses of males from Florida, Benin, Nigeria and Kenya, we found some regional differences in the responses of S. frugiperda males to the major compound, Z9-14:OAc and minor component Z9-12:OAc. However, we found no differences in male responses between the different African countries. All males showed significantly higher antennal responses to Z7-12:OAc than to E7-12:OAc. When comparing the mitotypes, we found that Florida R-type males showed higher responses to Z9-14:OAc, Z7-12:OAc and Z9-12:OAc than Benin R-type males, while C-type males from both regions responded equally to Z7-12:OAc. In addition, Florida R-type males showed higher responses to E7-12:OAc than Florida C-type males. Our study thus shows some differential physiological responses of S. frugiperda males towards the known sex pheromone compounds, including E7-12:OAc, but mostly in the different mitotypes. How these differences translate to field trap catches remains to be determined., (© 2024. The Author(s).)

The Asian cockroach, Blattella asahinai Mizukubo, first introduced to Florida in 1986, has been spreading throughout the southeastern United States. Populations can reach extremely high densities and cause damage to crops as well as become a nuisance in residential settings. Because the German cockroach, Blattella germanica L., is its closest extant relative, we characterized the B. asahinai male response to blattellaquinone, the sex pheromone of the German cockroach, in an effort to develop monitoring tools for B. asahinai. Electroantennogram (EAG) analysis was conducted on B. asahinai and B. germanica males and females, and revealed that the antennae of males of both species responded significantly more to blattellaquinone than females, and in both males and females absolute EAG responses of B. asahinai were greater than in B. germanica males and females, respectively. However, normalized male EAG response curves and ED50 values (effective dose to elicit 50% of maximal response) did not differ significantly between the two species. Results of field trapping experiments demonstrated that male B. asahinai were more attracted to blattellaquinone than any other life stage, and 10 μg of blattellaquinone attracted the most males. These results suggest that blattellaquinone or a similar compound might be a component of the sex pheromone of B. asahinai females., (© The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)