高氯土壤条件下烤烟对 Cl<sup>–</sup> 通道抑制剂的生理响应

商静; 许嘉阳; 范艺宽; 黄五星; 许自成

doi:10.11674/zwyf.16185

摘要:

目的在我国部分烟区，土壤氯离子含量高是造成烟叶氯离子含量高的一个主要因素，困扰着当地优质烟草的生产。研究氯离子通道抑制剂对烤烟成熟期叶片生理指标的影响，可为生产中合理降氯提供一定的参考。

方法2015 年在河南科技大学采用盆栽土培试验，设置四个处理，分别为 200 μmol/L NFA、200 μmol/L 9-AC、200 μmol/L Zn²⁺ 和蒸馏水，土壤含氯量为 50 mg/kg。于移栽后 30、45、60、75 d 灌根，每个处理每次每盆灌 1 L，连灌 3 天。测定了成熟期烤烟中部功能叶片中的CLC-Nt2 基因表达强度、光合色素含量、叶绿素荧光参数、相关元素积累量以及烟株生物量。

结果1) 与对照相比，施用抑制剂 Zn²⁺、NFA、9-AC 的烟株叶片中CLC-Nt2 的表达量显著降低，分别为对照的 82.22%、75.39%、72.19%，但 3 组抑制剂处理之间无显著差异。2) Zn²⁺、NFA、9-AC 处理的叶片叶绿素总含量较对照分别增加 20.15%、29.10%、45.52%，差异达到显著水平。同时，经不同抑制剂处理的叶片叶绿素荧光特性也表现出不同程度的增加，表明抑制剂可以减缓氯含量对烤烟 PSⅡ光合机构的伤害。3) 抑制剂对烤烟叶片中 Cl^–、K⁺、NO₃^– 的积累有明显影响。与对照相比，抑制剂处理的 3 组叶片中 Cl^– 含量显著降低，降幅在 18.17%～33.48%；K⁺ 含量和 NO₃^– 含量明显提高，增幅分别为 5.28%～10.20% 和 12.19%～25.24%，其中以 9-AC 处理的效果最佳。4) 抑制剂对烤烟生物量的合成有促进作用。与对照相比，施用抑制剂后烟株叶、茎、总干重显著提高，增幅分别为 17.02%～32.45%、10.54%～20.66% 和 13.21%～25.50%；而根干重增加幅度较小，仅为 5.94%～11.43%，根冠比显著降低。抑制剂的作用效果表现为 9-AC > NFA > Zn²⁺ > CK。

结论当植烟土壤中氯离子含量较高时，外施氯离子通道抑制剂能够对烤烟植株生长及体内一系列生理活动产生积极作用，在一定程度上缓解了氯害对烟草的不利影响。在本试验条件下，施用 200 μmol/L 9-AC 的烟株整体表现最优，而施用 200 μmol/L Zn²⁺ 的处理在基本满足降低叶片氯离子含量的同时降低了生产成本，这为生产中合理降氯提供了一定的参考。

Abstract:

ObjectivesHigh Cl^– content in soil is one of the main factors for high Cl^– content in tobacco leaves, which plagues tobacco production in some tobacco-growing area of China. Studying the effect of Cl^– channel inhibitors on the physiological and biological indexes of flue-cured tobacco would provide reference for approaching reasonable way of relieving the adverse impaction in tobacco production.

MethodsThree Cl^– inhibitors, Zn²⁺, NFA and 9-AC, were tested in a pot experiment, in which the used soil Cl^– content was 50 mg/kg. All the three Cl^– inhibitors were made into water solution of 200 μmol/L, each time irrigated 1 L per pot and consecutively for 3 days after the tobacco plants were transplanted for 30, 45, 60 and 75 days. The expression ofCLC-Nt2 gene, photosynthetic pigments content, chlorophyll fluorescence parameters, the related elements accumulation and plant biomass were measured in maturing leaves.

Results1) There was no significant difference in the expressions ofCLC-Nt2 gene in tobacco leaves among the Zn²⁺, NFA and 9-AC treatments, but they were all significantly lower than those in control, which were 82.22%, 75.39% and 72.19% respectively. 2) Inhibitor treatments could obviously raise the content of chlorophyll, with the increasing rate of 20.15% (Zn²⁺), 29.10% (NFA) and 45.52% (9-AC) separately compared with CK. The chlorophyll fluorescence in each treatment was higher than the control to a certain degree, which had remarkable benefit to decrease the damage of the PSⅡ photosynthetic apparatus in tobacco leaves. 3) Compared with control, the leaf Cl^– contents were significantly decreased by 18.17%～33.48%, while the K⁺ and NO₃^– were apparently increased by 5.28%–10.20% and 12.19%–25.24%, with the best effect in 9-AC. 4) Tobacco biomass were significantly affected by the use of inhibitors. Compared with CK, the dry weight of leaf, stem and the total biomass were significantly promoted and increased by 17.02%–32.45%, 10.54%–20.66% and 13.21%–25.50%, while the root dry weight increased only by 5.94%–11.43%. Therefore, the root-shoot ratio was comparatively lower. The biomass was showed in the order of 9-AC > NFA > Zn²⁺ > CK.

ConclusionsIrrigation of chloride channel inhibitors can alleviate chloride damage to tobacco plants planted in soil with relatively higher Cl^– content, because of the positive reactions to growth and physiological activities of flue-cured tobacco. 200 μmol/L 9-AC shows the best performance in the experimental condition, 200 μmol/L Zn²⁺ could meet the needs of reduction of chlorine ion in tobacco leaves with low cost in practice.

高氯土壤条件下烤烟对 Cl^– 通道抑制剂的生理响应

Physiological responses of flue-cured tobacco under the high chloride to chloride channel inhibitors

高氯土壤条件下烤烟对 Cl– 通道抑制剂的生理响应

Physiological responses of flue-cured tobacco under the high chloride to chloride channel inhibitors

高氯土壤条件下烤烟对 Cl^– 通道抑制剂的生理响应