Insect Chemical Ecology
ALBI-345 General Entomology
Aubrey Moore
Animals Need Information to Survive
- finding food
- finding mates
- escaping from predators
- avoiding dangerous environments (toxins, physical threats, etc.)
- for intraspecific communication
5 senses of humans and insects
| Sense | Human | Insect |
|---|---|---|
| Sight | eyes | compound eyes; simple eyes; ultraviolet |
| Hearing | ears | ears on legs or thorax; ultrasonic |
| Touch | skin | sensory hairs which poke through small holes in the exoskeleton |
| Smell | nose | antennae |
| Taste | mouth | tarsi (feet) and mouthparts |
Sensory processing
From Palial and Nidhi 2019. The potential use of semiochemicals in pest suppression.
Navigating to an odor source
Navigating to an odor source
From Carde 2016. Moth navgation along pheromone plumes
Navigating to an odor source
- flying insects detect wind direction by sensing ground speed with their eyes
- using flow of the visual surround to gauge wind direction is an optomotor reaction and this navigation system is termed optomotor anemotaxis.
- reference: Carde 2016. Moth navigation along pheromone plumes.
How pheromones are used for pest control
- pheromone traps for monitoring
- pheromone traps for population reduction
- attracticides
- mating disruption (confusion technique)
Example pheromone application
- Oriental fruit fly was successfully eradicated from the Mariana Islands in the 1960s by male annihilation
- An attracticide composed of methyl eugenol and an insecticide into fibre blocks were dropped from aircraft
- The entire male population was killed
Example pheromone application
- Pheromone traps failed to control coconut rhinoceros beetles on Guam
- High density trapping on Guam did not reduce damage
- In mark-release-recapture experiments, less than 10% of beetles were recaptured in pheromone traps baited with oryctalure
- Lowered attraction to oryctalure may be a characteristic of the CRB-G biotype
Coconut rhinoceros beetle pheromone trap
Research equipment
- Electroantennogram measures nerve response to an olfactory stimulus
- Olfactometer measures behavioral response to an olfactory stimulus
Electroantennogram
Olfactometer
YouTube: Insect sex pheromones as safe replacements for insecticides (6:18)
Youtube: Smellicopter (2:10)
References
[Wikipedia: Sense](https://en.wikipedia.org/w/index.php?title=Sense&oldid=1045083636)
[Palial and Nidhi 2019. The potential use of semiochemicals in pest suppression](https://medwinpublishers.com/IZAB/IZAB16000154.pdf)