ABSTRACT

Under various Arsenic (As) loads, growth of the tomato plant and changes in elemental uptake were investigated in this experimental study. Plants were transplanted into the As free soils and the loads of As were increased gradually with irrigation. The root and stem dry weights (DW) steadily increased with the increase of As concentration up to 1.5 mg L⁻¹, while the DW dropped to lower than the control plant’s DW when the As concentration was higher than mg L⁻¹. Although the leaves DW variations for the studied As concentrations were negligible, As application to the tomato plants positively affected the biomass amount of leaf. Considering the decrease in root/shoot ratio, the root growth was more promoted at low As concentrations, while the effect of As on the production rate of aboveground biomass could be neglected. When the As concentration was increased from 0.5 mg L⁻¹ to 3.0 mg L⁻¹, average 90% of the total applied As to the plants was accumulated in the root and As content in the root was enhanced about four times. Significantly higher levels of N, K, Mg, and Ca in the aerial parts of tomato than in roots were determined while the level of P was about equal in the tissues. Among the tissues, the lowest microelements; Cu, Mn, Fe, and Zn concentrations were determined at the root of control plant. However, especially at high As loads, the increase in the amount of microelements in the root was considerably higher compared to the stem and leaf.

摘要

本实验研究了在各种砷 (As) 负荷下，番茄植株的生长和元素吸收的变化。将植物移植到不含砷的土壤中，随着灌溉，砷的负荷逐渐增加。根和茎干重（DW）与As浓度的高达至1.5毫克的L的增加稳步增加^-1，而DW下降比对照植物的DW降低时As浓度高于毫克的L更高^-1. 尽管所研究的 As 浓度的叶子 DW 变化可以忽略不计，但 As 应用于番茄植物对叶子的生物量产生积极影响。考虑到根茎比的降低，低砷浓度下根系生长更受促进，而砷对地上生物量生产率的影响可以忽略不计。当 As 浓度从 0.5 mg L ^-1增加到 3.0 mg L ^{-1 时}, 平均 90% 的施用给植物的总砷在根中积累，根中的砷含量增加了约四倍。番茄地上部分的 N、K、Mg 和 Ca 含量显着高于根，而组织中 P 的含量大致相等。在组织中，微量元素最低；在对照植物的根部测定 Cu、Mn、Fe 和 Zn 浓度。然而，尤其是在高砷负荷下，与茎和叶相比，根中微量元素含量的增加要高得多。