Biomass and Chemical Composition of Tobacco Plants Under High Density Growth

Ten tobacco cultivars representing various tobacco types were directly seeded in the field at 70 to 80 plants per square meter and were harvested when 50 to 60 cm high. Biomass yield ranged from 44 to 70 metric tons per hectare, with Ky16 Mammoth having the highest yield. The Mammoth variety, however, had the lowest leaf/stalk ratio (1.77), whereas Coker 139 bad the highest (4.04). One metric ton of wet biomass produced about 6 to 8 kg of soluble protein, which is independent of the leaf/stalk ratio. Analyses of the deproteinized fibrous residues revealed that the levels of neutral detergent fiber, acid detergent fiber, cellulose, and apparent hemicellulose were comparable among the ten cultivars. A large variation of lignin content was observed among the dark green tobaccos. Burley, in general, had lower concentrations of starch and protein in the fibrous residue than the dark green tobacco. When compared with the deproteinized alfalfa fibrous residue, the low concentrations of lipids, lignin, and cellulose and a greater amount of apparent hemicellulose in the tobacco residue show its suitability as animal feed. The present results also indicate that the selection of tobacco genotypes is of importance for high density cultivation in the production of soluble protein and fibrous residue.