Flue-cured samples of 20 diverse genetic lines including six species-N. tabacum (flue-cured varieties SC58 and C139), N. sylvestris, N. tomentosiformis, N. otophora, N. glauca (yellow and purple flowered accessions), N. glutinosa-and 12 F₁ hybrids of each tobacco variety crossed with each of the other species were analyzed for free amino acids and for amino acids liberated from their total proteins by hydrolysis. Hydrolysates differed significantly among entries for many components but the magnitudes of these differences were generally too small to suggest biological importance. Large quantitative and discrete qualitative differences were found in the free amino acid extract of these divergent materials. For missing constituents, hybrids involving progenitor species most often resembled the N. tabacum parent, whereas the more distantly related hybrids emulated their wild parents. These data suggest that the responsible biochemical mechanisms might be amenable to genetic manipulation. No attempt was made to correlate these results with tobacco quality.

(Full article published with kind permission from "Tobacco International")