The Collaborative International Dictionary of English v.0.48:

Petune \Pe*tune"\, v. t. [imp. & p. p. Petuned; p. pr. & vb.
   n. Petuning.] [See Petunia.] (Agric.)
   To spray (tobacco) with a liquid intended to produce flavor
   or aroma.
   [Webster 1913 Suppl.]