断根、环割对烟草体内钾、钙、镁循环和积累的影响

Effects of the Root-cutting and Girding on the Circulation and Accumulation of the Potassium, Calcium and Magnesium in Tobacco

在网室内采用水培方式栽培烟草,于烟草打顶期及打顶后一周进行断根、环割处理,探讨断根、环割及断根+环割对烟草吸收钾、钙、镁和烟株体内钾、钙、镁循环、积累的影响。结果表明:断根降低了木质部汁液单位时间的钙、镁吸收循环量及钙、镁在韧皮部的积累量,而环割处理的结论刚好相反。断根+环割显著提高了木质部汁液单位时间的钾吸收循环量和烟叶的钾积累量,提高上部叶的钾含量,降低了中、下部烟叶钙、镁的含量,因此该处理提高烟叶品质的效果最好。

The tobacco plants were cultivated under solution culture conditions in the net room, and the root cutting and girdling were implemented in topping period and the eighth days after topping. The aim was to study the effects of the root cutting treatment, girdling treatment and the root cutting combined with girdling treatment on the circulation and accumulation of the potassium, calcium and magnesium in tobacco plants. The results showed that the root cutting treatment reduced the calcium, magnesium circulation amount of the xylem sap in unit time; however, the calcium, magnesium accumulation amount of the phloem; the girdling treatment had the opposite conclusion. The root cutting combined with girdling treatment increased the potassium circulation amount of the xylem sap in the unit time and the potassium circulation amount of the tobacco leaves, improved the potassium content in upper leaves and reduced the calcium and magnesium content in the middle, lower leaves. Therefore, this treatment reflected the best effect on improving the quality of the tobacco leaves.