Evaluation of four grasses for use in phytoremediation of Cs-contaminated arid land soil

Abstract

We used greenhouse experiments to evaluate cesium (Cs) uptake by four grasses, Agropyron spicatum (Pursh) Scribn & Smith, Leymus cinereus Scribn & Merr., Agropyron cristatum (L.) Gaertn. and Bromus tectorum L., to determine their potential as phytoremediation agents for Cs-contaminated soils. These four species grow well in the Intermountain region of western North America primarily on moderately coarse to coarsely textured soils where annual precipitation ranges from 20 to 50 cm. Whereas A. cristatum and B. tectorum are introduced species from Asia and the Mediterranean region of Europe, respectively, A. spicatum and L. cinereus are native to the Great Plains and Intermountain regions of North America. Plants were grown under two treatments each of: (1) soil Cs (ambient and 50 mg kg −1 + ambient), (2) soil fertility (ambient and ambient + 40 mg N kg −1 and 60 mg P kg −1 ), and 3) soil moisture (35% and 70% water holding capacity of the potted soils). Shoot Cs concentration in high soil Cs treatments was approximately ten times greater than in low soil Cs treatments. Even though shoot Cs concentrations tended to be lower in high soil Cs-high fertility-high soil moisture treatments than in high soil Cs-ambient fertility-low soil moisture treatments, total Cs uptake was greater because shoot biomass was approximately ten-fold greater. Shoots did not show signs of Cs toxicity in the high soil Cs treatments. We concluded, however, based on the low transfer factors (∼1.0) for all these grasses, that none were strong candidates as phytoremediation agents for Cs-contaminated soils.

Evaluation of the possibility to use the plant–microbe interaction to stimulate radioactive 137Cs accumulation by plants in a contaminated farm field in Fukushima, Japan

“…5). This variability in terms of Cs concentrations in the above-ground parts of plants without bacterial inoculation was found in previous reports that demonstrated that plants differ in their abilities to take up Cs in their natural habitats (Varskog et al 1994;Willey and Martin 1995;Cook et al 2007), in Cs-spiked soils or solutions (Cook et al 2009;Tang et al 2011) and in contaminated fields (Dushenkov et al 1999;Fuhrmann et al 2003).…”

Growth, biomass allocation, and water use efficiency of 31 apple cultivars grown under two water regimes

“…RWC was calculated as: RWC (%) = [(FW-DW)/(TW-DW)] 9 100. Water-holding capacity (WHC) was the amount of water removed during the drying process divided by the final DW; it was calculated according to a method modified from that of Cook et al (2009). Here, WHC (%) = (TW-DW)/DW 9 100.…”

A novel role for methyl cysteinate, a cysteine derivative, in cesium accumulation in Arabidopsis thaliana

“…Additionally, cesium-137, the radioactive isotope derived from nuclear waste and fallout, presents a serious health risk and environmental threat such that improved phytoaccumulation efficiency of cesium offers advantages in the light of phytoremediation also. Many plant species have been tested in the search for ‘hyperaccumulator plants’ of cesium, however most of the species tested suffer low absorption efficiency for practical application in the soil 4 5 6 7 8 9 10 11 12 . Various factors have been investigated and suggested as positive regulators of cesium accumulation in plants.…”