As a matter of fact, nicotine is synthesized exclusively in roots of the tobacco plant. So, it appears that there is no way to increase it in detached leaves. If you are interested in extraction nictoine from leaves, then the procedure used can affect the yield

Thank u sir, how could i extract the nicotine from leaves, could u tell me the procedure

Dear Rajan,

I am not a specialist in this, but even here on Researchgate you can find numerous papers on the subject when searching Publications with "nicotine" and "extraction", e.g., https://www.researchgate.net/publication/9072162_Effects_of_moisture_content_in_cigar_tobacco_on_nicotine_extraction._Similarity_between_soxhlet_and_focused_open-vessel_microwave-assisted_techniques?ev=pub_srch_pub

I suppose if you perform the search "nicotine extraction" in Google Scholar you will find hundreds of papers on the subject.

Regards,

Gederts

Article Effects of moisture content in cigar tobacco on nicotine ext...

Thank u sir