Abstract：
Nickel (Ni) is an essential element, but it can be phytotoxic in high concentration, which may be caused by high availability in soil solution. The objective of this study was to evaluate the effect of sources and doses of Ni applied to a dystrophic Red Latosol cultivated with sorghum on i) the availability of the metal in the soil; ii) the impact on biological and biochemical properties of the soil; iii) the absorption and distribution in sorghum plants; and iv) crop productivity. The experiment was carried out within a completely randomized design with two nickel sources [nickel(II) nitrate, Ni(NO3)2 and nickel(III) oxide, Ni2O3], three doses (35, 70, and 140 mg Ni kg-1 soil), plus controls without Ni, with 3 replications. The concentrations of Ni in the soil, soil microbial biomass (SMB), basal soil respiration (BSR), metabolic quotient (qCO2), fluorescein diacetate (FDA) hydrolysis, and urease activity were determined. The concentrations of Ni in the leaf diagnostic and in the plant (shoot, root, and grains) were also measured. In the soil, the concentrations of available Ni remained between 0.21 and 54.01 mg Ni kg-1. Ni2O3 contributed very little to the increase in available Ni. SMB and the FDA hydrolysis were not affected by the Ni source or Ni dose, but BSR and qCO2 had significant increase with Ni application rates, suggesting the soil microorganisms faced stress. Soil urease activity was affected by Ni dose but not by Ni source. The dose of Ni as Ni(NO3)2 decreased the metal concentration in the plant, while that of Ni2O3 increased it. Nickel source did not affect dry mass production of the plants, but grain yield was affected in a dose-dependent manner when Ni2O3 was the source of Ni.
摘要：
镍(Ni)是一种重要元素,但高浓度时可能会对植物产生毒性,这可能是由于土壤溶液的高可用性造成的。这项研究的目的是评估施用于高粱栽培的营养不良的红砖溶胶的Ni的来源和剂量对i)土壤中金属的有效性的影响;ii)对土壤的生物和生化特性的影响;iii)高粱植物中的吸收和分布;和iv)作物生产力。该实验是在完全随机的设计中进行的，具有两个镍源[硝酸镍（II），Ni(NO3)2和氧化镍(III),Ni2O3],三种剂量（35、70和140mgNikg-1土壤），加上没有Ni的控件，有3个重复。土壤中Ni的浓度,土壤微生物生物量(SMB)，基础土壤呼吸（BSR），代谢商（qCO2），荧光素二乙酸酯（FDA）水解，并测定了脲酶活性。叶诊断和植物中Ni的浓度(芽，根,和谷物)也被测量。在土壤中,有效镍的浓度保持在0.21至54.01mgNikg-1之间。Ni2O3对有效Ni的增加贡献很小。SMB和FDA水解不受Ni源或Ni剂量的影响，但BSR和qCO2随Ni施用量显著增加，这表明土壤微生物面临压力。土壤脲酶活性受Ni剂量的影响，但不受Ni源的影响。Ni作为Ni(NO3)2的剂量下降了植物中金属的浓度，而Ni2O3增加了它。镍源不影响工厂的干批量生产，但是当Ni2O3是Ni的来源时，晶粒产量受到剂量依赖性的影响。
