17. Analyze the data with Chemstation as well as MassHunter
software.
18. Search mass spectra against the Wiley library (275,000 spectra)
of electron impact mass spectra.
19. Substances recognized are certainly established by running the
pure substance and relating the retention time and mass spectra
of the assay-identified substance to the known substance.
20. In situations at which the retaining time is off by !0.5 min or
the mass spectra do not match, the assay-identified substance is
regarded unknown and never used in behavioral assessments.
4 Olfactometer Assay [139]
The captivation of nematodes to plant-produced substances is
tested using an olfactometer.
4.1 Materials
Required
l
Olfactometer.
Apparatus description:
– The olfactometer comprises a central glass chamber including
six similarly arranged side arms fitted to a female connector.
These arms are coupled to the center chamber by six glass
pots where plants or other sources of attractants are kept.
– Every single pot has a female connector.
– The connecting arms comprise two removable sections: one
is a glass tube with ground-glass connectors on each sides,
while the other part is a Teflon connector used to connect the
glass tube with the odor source pot.
– The custom-made Teflon connectors comprise an ultra-fine
metal screen (2300 mesh), averting the nematodes from
attaining the odor source pots.
l
Nematodes.
l
Sterile sand.
l
Attractant.
l
Filter disk.
l
Bearmann extractor.
l
Dissection microscope.
4.2 Procedure
1. Fill the six outer pots and the central pot of the olfactometer
with sterile sand approximately up to 5 cm from the rim of
the pots.
2. Place the attractant into three outer pots alternated with three
control pots that contained no attractant.
38
Chemical Ecology
software.
18. Search mass spectra against the Wiley library (275,000 spectra)
of electron impact mass spectra.
19. Substances recognized are certainly established by running the
pure substance and relating the retention time and mass spectra
of the assay-identified substance to the known substance.
20. In situations at which the retaining time is off by !0.5 min or
the mass spectra do not match, the assay-identified substance is
regarded unknown and never used in behavioral assessments.
4 Olfactometer Assay [139]
The captivation of nematodes to plant-produced substances is
tested using an olfactometer.
4.1 Materials
Required
l
Olfactometer.
Apparatus description:
– The olfactometer comprises a central glass chamber including
six similarly arranged side arms fitted to a female connector.
These arms are coupled to the center chamber by six glass
pots where plants or other sources of attractants are kept.
– Every single pot has a female connector.
– The connecting arms comprise two removable sections: one
is a glass tube with ground-glass connectors on each sides,
while the other part is a Teflon connector used to connect the
glass tube with the odor source pot.
– The custom-made Teflon connectors comprise an ultra-fine
metal screen (2300 mesh), averting the nematodes from
attaining the odor source pots.
l
Nematodes.
l
Sterile sand.
l
Attractant.
l
Filter disk.
l
Bearmann extractor.
l
Dissection microscope.
4.2 Procedure
1. Fill the six outer pots and the central pot of the olfactometer
with sterile sand approximately up to 5 cm from the rim of
the pots.
2. Place the attractant into three outer pots alternated with three
control pots that contained no attractant.
38
Chemical Ecology