不同浓度钾营养液对烟草苗期矿质营养吸收与积累的影响

Effect of K^+ concentration on absorption and accumulation of mineral nutrients during tobacco seedling stage

采用水培的方法,研究了烟草苗期在不同浓度钾营养液中对几种矿质养分的吸收与积累的影响。结果表明,在其它养分形态与浓度一致条件下,随钾浓度从75 mg/L提高到900 mg/L,烟草生长量呈抛物线型变化,在供钾浓度为300 mg/L时积累量最大。烟株中钾、锌含量随供钾水平的提高而增加,当供钾水平为900 mg/L时,钾、锌含量达到最大;钙、镁、铜含量随着钾浓度的提高均减少;氮、磷、锰的含量呈抛物线型变化,但是氮、磷含量在钾浓度为300 mg/L时达到最大,而锰含量在供钾水平为450 mg/L达到最大。随供钾水平从75 mg/L增加到900 mg/L,烟株内氮、磷、钙、锰、钾积累量均呈抛物线型变化,当钾浓度为300 mg/L时,氮、磷、钙、锰积累量达到最大,而钾积累量在钾浓度为450 mg/L时达到最大;镁、铜在烟株内积累量持续下降;而锌积累量则持续上升。烟草叶片中各元素含量和积累量的变化趋势与整株基本一致。

The effect of K^＋ concentration on the absorption and accumulation of several mineral nutrients in tobacco was studied by water-culture method. The results showed that, with the increasing supply of K^＋ from 75 mg/L to 900 mg/L, the tobacco biomass varied in a shape of parabola and got a peak value at 300 mg/L of K^＋ . The K^＋ and Zn content of tobacco was increased with K^＋ supplied in solution, and when K^＋ concentration was 900 mg/L, the K and Zn content in tobacco reached the maximum. And the Ca, Mg and Cu content was reduced with K^＋ supplied in solution. The N, P and Mn content varied in a shape of parabola and N and P content got a peak value at 300 mg/L of K^＋ , while Mn at 450 mg/L. With the increasing supply of K^＋ from 75 mg/L to 900 mg/L, the accumulation of N, P, Ca, Mn and K in tobacco varied in a shape of parabola and N, P, Ca and Mn got a peak value at 300 mg/L of K^＋ , while K got the peak value at 450 mg/L. The accumulation of Mg and Cu was lowered steadily, while Zn was increased. The changes of the content and accumulation of the determined nutrients in tobacco leaves with the increasing of K^＋ were similar to those in the whole plant.