切根对烤烟根系生长及化学成分的影响

Effect of root-cutting on root growth and chemical composition of flue-cured tobacco

以烤烟品种K 326为试验材料,采用盆栽的方法,设不切根(CK)、切根5 cm(T1)、切根10 cm(T2)3个处理。研究了不同切根长度对烤烟根系生长发育及烟叶中氮、钾、烟碱含量的影响。结果表明,处理后14 d根长表现为T1>CK>T2,但各处理间没有显著差异,而此时根系活力却表现为T2>T1>CK;烟叶成熟后干物质量在根、茎、叶方面都表现为T1>T2>CK;烟叶内在化学品质方面氮、烟碱含量表现为T1>T2>CK,且各处理间存在显著差异,而钾含量则为T1>CK>T2;对根系指标与烟叶内在化学成分的相关性分析表明,与氮、烟碱含量相关性最大的为根系干物质量,而与钾含量相关性最大的为根系长度。

Pot experiments were carried out and three treatments were designed （T1 ： no intertilling; T2 and T3 ：intertilling at the depth of 5 and 10 cm） to study the effect of different depth of root-cutting on the growth and development of root system and the content of nitrogen, potassium and nicotine in flue-cured tobacco of K326 variety. The results showed that on the 14th day after the treatment of root- cutting the root length was T1 〉 CK 〉 T2, but there was no significant difference between each treat- ment. However, the root activity showed up as T2 〉 T1 〉 CK at the same time; the dry matter on root stems and leaves showed up as T1 〉 T2 〉 CK after the maturity of tobacco leaves; in the aspect of in- ternal chemical component of tobacco leaves, the nitrogen and nicotine content showed up as T1 〉 T2 〉 CK, and there was significant difference between each treatment, but the content of potassium showed up as T1 〉 CK 〉 T2. The correlation analysis between root properties and internal chemical component indicated that the weight of root system had maximal relationships with the content of nitro- gen and nicotine, and the length of root had the highest correlation to the content of potassium.