Effects Of Exdogenous Plant Hormone On Concentration Of Nicotine And Hormone In Flue-cured Tobacco

The experiments were done from 1999 to '2001. Effects of exdogenous hormone on content of Nicotine and hormone were studied in flue-cured tobacco which were treated with exdogenous hormone when toped and untoped. Results indicated that content of Nicotine and hormone were different in differently treated tobacco.When tobacco were toped, the content of Nicotine get up to 2-3 times of that in leaf and increased by 50 percent in root. Meanwhile, the conent of IAA and GA3 decreased, but the content of ABA and ZR increased. Changes of GA3 and ZR were smaller than those of IAA and ABA. The content of plant hormone in leaf was higher than that in root. The content of IAA in tobacco was the highest, then ABA. The order of content of hormone was : IAA>ABA>ZR>GA3. In general, change of hormone was consistent with that of Nicotine.In the toped and untoped tobacco when applied with hormone, both content of IAA and GA3 increased but others decreased in tobacco that treated with IAA and GA3; The content of ABA increased significantly but the content of IAA and GA3 decreased when applied with ABA. When appliedwith GA3, the content of GA3 increased and the content of Nicotine decreased. But TIBA made Nicotine become higher. The results showed that IAA and GA3 significantly promoted content of IAA and GA3 in tobacco, at the same time, the content of Nicotine decreased; But the content of IAA and GA3 decreased and that of Nicotine increased when applied with ABA. This indicated that plant hormone acted as carrier of signal in the course of signal transfer of biosynthsis of Nicotine.When content of Nicotine increased, protein decreased in leaf and root of toped tobacco. This probably because the content of IAA decreased rapidly and acted as the first signal to transfer to root in toped tobacco, and this made the second signal 桝BA and ZR increased, activated biosynthsis of Nicotine.One of the question about tobacco quality was that content of Nicotine was too high and unfit to industry. So it is feasible that application with plant hormone to regulate content of Nicotine in the course of production. After toping, the content of Nicotine was decreased by IAA, but increased by ABA. Because biosynthsis of Nicotine was rapid in the 0-10 days after toping, if plant hormone was used to regulate content of Nicotine in production, it had better be applied in the toping day.