Davis M A, Murphy J F, Boyd R S
School of Forestry & Wildlife Sciences, Auburn University, AL 36849-5418, USA.
J Environ Qual. 2001 Jan-Feb;30(1):85-90. doi: 10.2134/jeq2001.30185x.
Hyperaccumulated Ni can defend plant tissues against herbivores and pathogens. The effectiveness of this defense, however, has not been tested with a viral pathogen. Turnip mosaic virus (TuMV) accumulation was studied in two serpentine species of Streptanthus with different Ni uptake abilities. Plants of a Ni hyperaccumulator, milk-wort jewelflower (S. polygaloides Gray), and a non-hyperaccumulator, plumed jewelflower (S. insignis Jepson), were grown on Ni-amended and unamended soils. Plants were inoculated with TuMV at three different phenological stages: basal rosette, bolting, and flowering. Susceptibility of experimental plants to TuMV was determined either by the magnitude of TuMV accumulation (measured by indirect enzyme-linked immunosorbent assay [ELISA]) or by plant survival. Streptanthus polygaloides plants grown on high-Ni soil were more susceptible to TuMV than low-Ni S. polygaloides at all three phenological stages. All rosette and pre-bolt S. insignis plants were infected by TuMV, but survival and TuMV accumulation were not significantly affected by soil Ni. At flowering, only high-Ni S. polygaloides plants became infected. For S. polygaloides, elevated tissue Ni concentrations enhanced TuMV infection instead of defending plants from the virus. To reduce risks to nearby agricultural crops, future phytoremed. iation and phytomining operations using this species should incorporate management plans to prevent the creation of artificial reservoirs of TuMV inoculum.
超积累的镍可以保护植物组织免受食草动物和病原体的侵害。然而，这种防御的有效性尚未在病毒病原体上得到验证。我们研究了两种对镍吸收能力不同的蛇纹石链珠草属植物中芜菁花叶病毒（TuMV）的积累情况。在添加镍和未添加镍的土壤上种植了镍超积累植物——乳草叶链珠草（Streptanthus polygaloides Gray）和非超积累植物——羽状链珠草（Streptanthus insignis Jepson）。在三个不同的物候阶段给植物接种TuMV：基生莲座叶丛期、抽薹期和开花期。通过TuMV积累量（通过间接酶联免疫吸附测定[ELISA]测量）或植物存活率来确定实验植物对TuMV的易感性。在所有三个物候阶段，生长在高镍土壤上的乳草叶链珠草比低镍的乳草叶链珠草对TuMV更易感。所有莲座叶丛期和抽薹前的羽状链珠草植物都被TuMV感染，但土壤镍含量对其存活率和TuMV积累没有显著影响。在开花期，只有高镍的乳草叶链珠草植物被感染。对于乳草叶链珠草来说，组织镍浓度升高增强了TuMV感染，而不是保护植物免受病毒侵害。为了降低对附近农作物的风险，未来使用该物种的植物修复和植物采矿作业应纳入管理计划，以防止形成TuMV接种物的人工储存库。
