Chen Ting, Li Ting-Qiang, Yang Jin-Yan
Department of Architecture and Environment, Sichuan University, Chengdu, Sichuan, China.
Department of Environmental and Resource Sciences, Zhejiang University, Hangzhou, Zhejiang, China.
Environ Toxicol Chem. 2016 Mar;35(3):695-701. doi: 10.1002/etc.3226. Epub 2016 Feb 3.
To elucidate the physiological and morphological responses generated by vanadium (V) in plants, hydroponic culture experiments were performed with swamp morning glory (Ipomoea aquatica Forsk) exposed to 0 mg L(-1) to 2.50 mg L(-1) pentavalent V [V(V)] in Hoagland nutrient solutions. The concentration of chlorophyll a, chlorophyll b, and carotene peaked at a V(V) concentration of 0.05 mg L(-1) and gradually decreased at higher V(V) concentrations. Similarly, the plant biomass was stimulated at low levels of V(V) and was inhibited when V(V) concentrations exceeded 0.1 mg L(-1). Pentavalent V had negative effects on the uptake of phosphorus (P) by roots, shoots, and leaves. The biological absorption coefficients of V of the roots were higher than those of the aerial parts. Under low concentrations of V(V) exposure, the predominant species of V in the aerial parts was tetravalent V [V(IV)], whereas V(V) became more prevalent when concentrations of V(V) in the solution was higher than 0.50 mg L(-1). In the roots, however, the concentrations of V(V) were always higher than those of the V(IV), except in the control group. Organelles in the V(V)-treated leaves were distorted, and the periplasmic space became wider. These results indicate V(V) has concentration-dependent effects on the physiological properties of swamp morning glory, whereas the plant has the ability to develop self-protective function to adapt to the toxicity of V(V).
为阐明钒（V）对植物产生的生理和形态学响应，在水培试验中，将蕹菜（Ipomoea aquatica Forsk）置于霍格兰营养液中，使其暴露于0 mg L⁻¹至2.50 mg L⁻¹的五价钒[V(V)]环境下。叶绿素a、叶绿素b和类胡萝卜素的浓度在V(V)浓度为0.05 mg L⁻¹时达到峰值，并在更高的V(V)浓度下逐渐降低。同样，低水平的V(V)刺激了植物生物量的增长，而当V(V)浓度超过0.1 mg L⁻¹时则受到抑制。五价钒对根、茎和叶吸收磷（P）有负面影响。根部对V的生物吸收系数高于地上部分。在低浓度V(V)暴露下，地上部分V的主要形态是四价钒[V(IV)]，而当溶液中V(V)浓度高于0.50 mg L⁻¹时，V(V)变得更为普遍。然而，在根部，除对照组外，V(V)的浓度始终高于V(IV)。经V(V)处理的叶片中的细胞器发生变形，周质空间变宽。这些结果表明，V(V)对蕹菜的生理特性具有浓度依赖性影响，而植物具有发展自我保护功能以适应V(V)毒性的能力。
