Effects of Combined Tobacco Stem Organic Fertilizer on Root Development and Mineral Element Contents of Flue-cured Tobacco

To explore the effects of a tobacco stem organic fertilizer combined with other organic fertilizers on tobacco root system, mineral nutrients and tobacco leaf quality, a pot experiment was conducted with different amount of tobacco stems mixed with organic fertilizers. The tobacco stem mixed organic fertilizers used were tobacco stem organic fertilizer, sesame cake and humic acids. The results showed that tobacco the stem organic fertilizer combined with organic fertilizers could significantly promote the root biomass and root physiological activities, especially at the vigorously growing stage and the toping stage. The volume growing rate, dry weight growing rate, root activity and root active absorb area all appeared peak during this stage. At later stages of development tobacco stems combined with organic fertilizers could slow down the senescence of root system. The 500 g/pot treatment had the best effect with its root volume, root dry weight, root vigor and root absorb total area increased by 60.77%, 114.76%, 53.12% and 148.36% compared with control, respectively. The study also revealed that tobacco stems combined with organic fertilizers played a positive role in promoting mineral contents of flue-cured tobacco. Tobacco stems combined with organic fertilizers enhanced absorption of mineral elements, especially P, Zn, Fe, and Mn. Application of tobacco stems mixed organic fertilizers with 500 g/pot was therefore the optimum treatment. This provides theory gist for cultivating strong tobacco root system, balancing the mineral nutrients of flue-cured tobacco and for the decomposition application of tobacco stem organic fertilizers.