Method for judging quality of fresh tobacco sample in tobacco metabonomics on basis of alkaloid

The invention provides a method for judging the quality of a fresh tobacco sample in tobacco metabonomics on the basis of alkaloid. The content ratio of nicotyrine to 4,4'-bipyridin in fresh tobacco is taken as an index, the quality of the fresh tobacco sample in metabonomics is judged, and a basis is provided for selection of qualified samples in the metabonomics. The method is accurate, reliable, simple and feasible and can provide reference for metabolic feature analysis of tobacco and research on related tobacco metabonomics.