If it were me, I would use headspace extraction or solid-phase microextraction（SPME）

Siqi Tang

Noted, how about the process? Is it better to extract the plant parts or capture the VOCs directly from the living plant (then processed with SPME)?

Dear Dian,

I would suggest the paper below and follow the methodologyArticle Response of Aphid Parasitoids to Volatile Organic Compounds ...

Dian Nurul Izzati

In my opinion, you should let the Herbivore eat your plant and then extract the entire plant with the Herbivore on it(Chopping the plant and then extracting it will cause the plant to produce some unintended VOCs).

Qasim Ahmed Thank you for the suggestion, I have already read it.

Siqi Tang Noted, thank you for the help.