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bioRxiv · 10.1101/2021.09.16.460697

No impact of biocontrol predator on development time or size of surviving Aedes albopictus under optimal nutritional availability

Russell, M. C.·Cator, L. J.
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Abstract

Cyclopoid copepods have been applied successfully to limit populations of highly invasive Aedes albopictus mosquitoes that can transmit diseases of public health importance. However, there is concern that changes in certain mosquito traits, induced by exposure to copepod predation, might increase the risk of disease transmission. In this study, third instar Ae. albopictus larvae, hereafter referred to as "focal individuals", were exposed to Megacyclops viridis predator cues associated with both consumption of newly-hatched mosquito larvae and attacks on focal individuals. The number of newly-hatched larvae surrounding each focal larva was held constant to control for density effects on size, and the focal individuals day of pupation and wing length were recorded for each replicate. Exposing late instar Ae. albopictus to predation decreased their chances of surviving to adulthood, and three focal larvae that died in the predator treatment showed signs of melanization, indicative of wounding. Among surviving focal Ae. albopictus, no significant difference in either pupation day or wing length was observed due to copepod predation. The absence of a significant sublethal impact from M. viridis copepod predation on surviving later-stage larvae in this analysis supports the use of M. viridis as a biocontrol agent against Ae. albopictus. Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=106 SRC="FIGDIR/small/460697v2_ufig1.gif" ALT="Figure 1"> View larger version (9K): org.highwire.dtl.DTLVardef@1abaabborg.highwire.dtl.DTLVardef@1561651org.highwire.dtl.DTLVardef@d325a7org.highwire.dtl.DTLVardef@4d1830_HPS_FORMAT_FIGEXP M_FIG C_FIG

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Russell, M. C., Cator, L. J.. 2021-09-17. No impact of biocontrol predator on development time or size of surviving Aedes albopictus under optimal nutritional availability. https://doi.org/10.1101/2021.09.16.460697

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