不同浓度钙营养液对烟草矿质营养吸收与积累的影响

Effect of Ca^(2+) Concentrations on Absorption and Accumulation of Mineral Nutrients in Tobacco

本文采用温室水培的方法,研究了不同的钙素供应水平对烟草各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,随着钙浓度从75mgL-1提高到900mgL-1,烟草生长量呈抛物线型变化。钙浓度为150mgL-1时烟株干物质量最大。超过150mgL-1,随钙的增加而下降,当钙素达900mgL-1(K/Ca为1/6)时,烟株生长严重受抑。随着供钙水平由低到高,烟株氮、磷、钾、锌、锰含量均呈抛物线型变化,含钙量呈直线上升关系,而镁和铜含量则随钙浓度提高而显著下降。烟株各养分积累量均随营养液钙浓度提高呈抛物线型变化,但不同养分出现最大积累量时的营养液钙浓度却不相同。不同供钙水平上烟叶中各元素含量的变化特征与全株的结果基本一致。在低钙浓度范围(75~300mgL-1),钙对钾有协合关系,增钙促进提钾,大于300mgL-1后有拮抗作用,提钙导致降钾。钙与镁、锌、铜、锰间也存在明显的交互作用。烟叶中各元素含量与积累量的变化趋势与整株基本一致。

Using the method of water-culture, this paper studied the effect of Ca^(2+) on the absorption and accumulation of several mineral nutrients in tobacco. The results showed that, with the increasing supply of Ca^(2+) from 75mg L^(-1) to 900mg L^(-1), the tobacco biomass varied in a shape of parabola and got a peak value at 150mg L^(-1) of Ca^(2+) .The contents of N, P, K, Zn and Mn also changed in parabola relation with Ca^(2+) concentrations in solution. The Ca^(2+) content in tobacco increase steadily with Ca^(2+) supply in solution,while the contents of Mg^(2+) and Cu^(2+) lowered accordingly. The accumulations of the determined nutrients were all in parabola relation to the increased Ca^(2+) but the Ca^(2+) concentrations at which the maximum accumulation of certain nutrient occurred were different. When Ca^(2+) was diluted (75-300mg L^(-1)), increasing Ca^(2+) could promote K^+ absorption by tobacco, while inhibited K^+ absorption when Ca^(2+) concentration was over 300mg L^(-1).There were also significant interactions between Ca^(2+) and Mg^(2+) , Zn^(2+) , Cu^(2+) and Mn^(2+) , respectively. The changes of the contents and accumulation of the determined nutrients in tobacco leaves with the increasing of Ca^(2+) were similar to those in the whole plant.