Zinc Hyperaccumulation and Uptake byPotentilla GriffithiiHook

Abstract

The ability of Potentilla griffithii Hook var. velutina Cardot to hypaeraccumulate zinc (Zn) was identified through field survey and hydroponic experiments. Our results showed that P. griffithii could be classified as a new Zn hyperaccumulator. Zn concentrations in the shoots of P. griffithii averaged 6250 mg kg(-1) (3870-8530 mg kg(-1)) growing in Zn-rich soils. The highest Zn concentration was observed in the leaves of P. griffithii at 22,990 mg kg(-1). The fact that P. griffithii was able to grow in a mining soil with a Zn concentration of 193,000 mg kg(-1) without showing a major sign of phytotoxicity demonstrated its high tolerance to Zn. When growing in hydroponic systems, P. griffithii accumulated a maximum 26700 mg kg(-1) zinc concentration in the shoots, indicating the ability of this species to effectively take up and translocate Zn. Translocation factors (the ratio of Zn concentration in shoot to root) of 1.1 to 1.6 were obtained. Compared to the control, dry biomass of P. griffithii in 160 mg L(-1) Zn treatment increased 66.6% (P < 0.05). The time-course experiment showed that the maximum Zn concentration at 100 mg L(-1) Zn treatment was found at 16 d, much later than that of the 10 mg L(-1) Zn treatment, which might be an attribution of a accumulating mechanism or detoxification of a plant. The report of a new Zn hyperaccumulator provides a new plant species for the phytoremediation of contaminated soil and for the research on mechanisms of Zn hyperaccumulation in plants.

Interaction of cadmium and zinc on accumulation and sub-cellular distribution in leaves of hyperaccumulator Potentilla griffithii

“…It is interesting to note that the stimulatory effect on plant biomass can also be induced by non-essential element Cd. Similar increase in biomass was observed at 160 mg L −1 Zn for 21 days [19] and 20 mg L −1 Cd exposed for 60 days [21] in the same plant. However, the plant growth was sustained similar to control when the concentration of Zn increased to 240 mg L −1 and a decrease in plant growth was evident at the highest concentration of 320 mg L −1 Zn (1.96 fold higher than the present study) for 21 days [19].…”

“…Similar increase in biomass was observed at 160 mg L −1 Zn for 21 days [19] and 20 mg L −1 Cd exposed for 60 days [21] in the same plant. However, the plant growth was sustained similar to control when the concentration of Zn increased to 240 mg L −1 and a decrease in plant growth was evident at the highest concentration of 320 mg L −1 Zn (1.96 fold higher than the present study) for 21 days [19]. Irrespective of whether they are beneficial or toxic, stimulatory effect to some extent was also observed in other hyperaccumulators, such as Arabis paniculata [24], S. alfredii [25] and Viola baoshanensis [26], but inhibitory at higher concentrations (hormetic response).…”

“…Potentilla griffithii Hook is a recently found Cd/Zn hyperaccumulator plant. This species has the ability to tolerate and accumulate high concentrations of both Zn [19] and Cd [20] from soil and nutrient solutions, suggesting that altered competitive interactions of both metals may occur in this plant. Hu et al [21] demonstrated the tolerance and accumulation ability of Cd and Zn in P. griffithii by sub-cellular distribution in root and leaf tissues using TEM.…”

Hyperaccumulation capacity and resistance physiology of &lt;italic&gt;Microsorum pteropus&lt;/italic&gt;, an aquatic fern to cadmium

“…超富集植物能通过根部吸收 重金属并将其转运富集于各组织中, 同时不会对植物 的生长造成影响 [5] , Cd超富集植物特指能在组织内富 集超过100 mg/kg Cd的植物 [6] 根据Brooks等人 [7] 的定义, 目前发现的超富集植 物有超过500种, 广布于50个科. 其中Cd超富集植物 16种, 分别为禾秆蹄盖蕨(Athyrium yokoscense) [8] 、拟 南芥(Arabidopsis thaliana) [9] 、遏蓝菜(Thlaspi arvense L.) [10] 、 宝 山 堇 菜 (Viola baoshanensis) [11] 、 印 度 芥 菜 (Brassica juncea) [12] 、东南景天(Sedum alfredii) [13] 、筷 子 芥 属 (Arabis L.) [14] 、 长 柔 毛 委 陵 菜 (Potentilla griffithii) [15] 、龙葵(Solanum nigrum L.) [16] 、商陆(Phytolacca acinosa Roxb) [17] 、叶用红菾菜(Beta vulgaris var. cicla L.) [18] 、球果蔊菜(Rorippa globosa (Turcz.…”

Hyperaccumulative Characteristics of Weed Species to Heavy Metals

“…Although more than 400 species of hyperaccumulators have been documented in the world (Brooks et al 1998;Reeves 2003), new hyperaccumulators are being continually discovered, such as the Cr-hyperaccumulator Leersia hexandra (Zhang et al 2007), the Mn-hyperaccumulator Chengiopanax sciadophylloides (Mizuno et al 2006), the Zn-hyperaccumulaor Potentilla griffithii (Qiu et al 2006), and the Cd-hyperaccumulator Thlaspi praecox (Tolra et al 2006). Despite such discoveries of many hyperaccumulator plants, phytoextraction as a technology is not practically used on a large scale.…”