Knowledge on the ecophysiology of cobalt hyperaccumulator species is limited. The nickel hyperaccumulator Rinorea cf. bengalensis from Borneo can accumulate high concentrations of cobalt in nature. This study investigates the cobalt accumulation potential of Rinorea cf. bengalensis in relation to nickel concentrations in soils and the subsequent tissue and cellular-level distributions of cobalt, nickel and major cations. Seedlings of Rinorea cf. bengalensis were grown in mixed treatments on ultramafic soil containing a high concentration of available nickel. Cobalt and nickel salts were then added to the soil to study their interactions. The tissue and cellular-level distributions of cobalt, calcium, nickel, and potassium were investigated using synchrotron-based X-ray fluorescence microscopy. The maximum foliar cobalt concentration reached 1200 μg g−1. Accumulation of cobalt competed with nickel accumulation although nickel seems to stimulate cobalt phloem translocation. Plants suffered toxicity in the treatment with the highest soil cobalt concentration. Cobalt and nickel have contrasting distribution patterns in the leaves of Rinorea cf. bengalensis, with cobalt mainly excreted on the surface of the leaves, whereas nickel is localised in foliar epidermal cells. Rinorea cf. bengalensis can accumulate high concentrations of cobalt, but is intrinsically more tolerant to nickel. It does not rely on a similar sequestration mechanism for both metals, which could explain the lesser tolerance for cobalt. Nickel appears to be essential for the plant to tolerate high cobalt concentrations. Further studies intending to develop agronomic practices are needed to determine the viability of Rinorea cf. bengalensis for nickel-cobalt agromining.

中文翻译：

---

Rinorea 中的钴超积累 参见。来自沙巴的 bengalensis（紫罗兰科）：钴的积累潜力和组织和细胞水平分布

关于钴超富集物种生态生理学的知识是有限的。镍超富集植物 Rinorea 参见。来自婆罗洲的孟加拉人可以在自然界中积累高浓度的钴。本研究调查了 Rinorea cf. 的钴积累潜力。bengalensis 与土壤中镍浓度以及随后钴、镍和主要阳离子的组织和细胞水平分布有关。Rinorea 的幼苗 cf. bengalensis 在含有高浓度有效镍的超基性土壤上以混合处理方式生长。然后将钴盐和镍盐添加到土壤中以研究它们的相互作用。使用基于同步加速器的 X 射线荧光显微镜研究钴、钙、镍和钾的组织和细胞水平分布。最大叶面钴浓度达到 1200 μg g-1。尽管镍似乎刺激钴韧皮部易位，但钴的积累与镍的积累竞争。植物在土壤钴浓度最高的处理中遭受毒性。钴和镍在 Rinorea 的叶子中具有对比的分布模式，参见。bengalensis，钴主要排泄在叶子表面，而镍则分布在叶表皮细胞中。Rinorea 参见。bengalensis 可以积累高浓度的钴，但本质上对镍更耐受。它不依赖于两种金属的类似螯合机制，这可以解释对钴的较低耐受性。镍似乎是植物耐受高钴浓度所必需的。需要进一步研究旨在开发农艺实践，以确定 Rinorea 的可行性，参见。bengalensis 用于镍钴农杆菌开采。