Abstract:

【Objective】 In order to provide a theoretical basis for the potassium regulation metabolism, this paper analyzed the effects of topping on the expression of potassium channel genes in flue-cured tobacco. 【Method】 Real-time fluorescence quantitative PCR was used to detect the relative expression change of potassium channel genes, and endogenesis auxin (IAA) was detected by ELISA in tobacco through pot experiments. 【Result】 As compared with the control, the potassium accumulation in whole plant of decapitated tobacco decreased and there was more potassium distribution in leaves and roots. The expressions of NKT1 and NTORK1 genes in leaves were inhibited by topping, but not in roots. The expression of both NKT1 and NTORK1 in leaves was higher than that in roots within 24 h, except 14 d while it was reversed in the two tissues. The variations of expression of potassium channel genes in roots could control potassium accumulation and regulate K+ concentration in aerial parts. Further results showed that the level of endogenesis IAA, which declined in leaves and increased in roots by 140.7% at 14 d compared to the control plant, was attributed to the expression change of potassium channels. 【Conclusion】 The variations of expression of potassium channel genes are likely to be caused by the endogenesis hormone in tobacco after topping, and it has a direct impact on the potassium accumulation and distribution simultaneously.

Key words: decapitation, flue-cured tobacco, potassium channel, potassium