Selective odor perception in the soil collembolaOnychiurus armatus

Area of Science:

• Ecology
• Chemical Ecology
• Soil Biology

Background:

• Fungivorous soil collembolans, like Onychiurus armatus, play a crucial role in soil ecosystems.
• Understanding their olfactory responses is key to comprehending soil food web dynamics.

Purpose of the Study:

• To investigate the olfactory responses of Onychiurus armatus to volatile compounds from preferred fungi.
• To identify specific odor compounds that attract or deter collembolans.

Main Methods:

• Volatile compounds from Monierella isabellina and Verticillium bulbillosum were collected and analyzed using Gas Chromatography-Mass Spectrometry (GC-MS).
• Olfactory responses were tested in a Y-shaped olfactometer bioassay.
• Identification of volatile compounds was achieved through electron impact and chemical ionization mass spectrometry.

Main Results:

• Onychiurus armatus exhibited attraction to common odors (CO2, 2-methyl-1-propanol) and specific odors (1-heptene).
• Compounds like decanal and 2-octene caused arrestment.
• Low concentrations of ethyl acetate and 1-pentanol were sufficient attractants.
• 1-heptene and 1-octen-3-ol, specific to V. bulbillosum, were identified as potential key attractants.

Conclusions:

• The olfactory response of Onychiurus armatus is complex, involving attraction and arrestment cues.
• Specific volatile compounds from fungi, particularly 1-heptene and 1-octen-3-ol, likely mediate the preference of Onychiurus armatus for Verticillium bulbillosum.