Project description:Background and aimsSalt has been shown to affect Cd translocation and accumulation in plants but the associated mechanisms are unclear. This study examined the effects of salt type and concentration on Cd uptake, translocation and accumulation in Carpobrotus rossii.MethodsPlants were grown in nutrient solution with the same Cd concentration or Cd2+ activity in the presence of 25 mm NaNO3, 12.5 mm Na2SO4 or 25 mm NaCl for ?10 d. Plant growth and Cd uptake were measured and the accumulation of peptides and organic acids, and Cd speciation in plant tissues were analysed.Key resultsSalt addition decreased shoot Cd accumulation by >50 % due to decreased root-to-shoot translocation, irrespective of salt type. Synchrotron-based X-ray absorption spectroscopy revealed that, after 10 d, 61-94 % Cd was bound to S-containing ligands (Cd-S) in both roots and shoots, but its speciation was not affected by salt. In contrast, Cd in the xylem sap was present either as free Cd2+ or complexes with carboxyl groups (Cd-OH). When plants were exposed to Cd for ?24 h, 70 % of the Cd in the roots was present as Cd-OH rather than Cd-S. However, NaCl addition decreased the proportion of Cd-OH in the roots within 24 h by forming Cd-Cl complexes and increasing the proportion of Cd-S. This increase in Cd-S complexes by salt was not due to changes in glutathione and phytochelatin synthesis.ConclusionsSalt addition decreased shoot Cd accumulation by decreasing Cd root-to-shoot translocation due to the rapid formation of Cd-S complexes (low mobility) within the root, without changing the concentrations of glutathione and phytochelatins.
Project description:The complete mitochondrial genome of Notothenia rossii was obtained using PacBio Sequel long-read sequencing platform. The mitogenome of N. rossii was circular form and 18,274 bp long, which consists of 13 protein-coding genes, 24 tRNAs, 2 rRNAs, and non-coding control region. Particularly, we found duplicated tRNAThr and tRNAPro in addition to the typical 22 tRNAs. The phylogenetic tree revealed that N. rossii was most closely related to N. coriiceps among species in the Nototheniidae clade within the suborder Notothenioidei.
Project description:Nowadays, toxic metals accumulation in soil texture due to anthropogenic activities is a major form of pollution, which can lead to worldwide concerns; however, there are many treatment methods to remove them from soil such as phytoremediation. The carpobrotus rossii, has shown great potential to tolerate high salinity and accumulate Cd from contaminated soils. The experiments, in this study, are analyzed and optimized by Central Composite Design (CCD) as method and using Response Surface Methodology (RSM) package in R software. The Cd removal by root and the whole plant followed the quadratic model and the R2 values were 94.95 and 94.81, respectively. The results showed that a decrease in NaCl concentration in Cd-containing solution can increase the phytoremediation process of Cd by carpobrotus rossii, significantly. The optimum conditions for 58% Cd removal by the whole plant, predicted through a CCD response surface methodology model were as follows: initial Cd concentration of 49 mgKg-1,NaCl concentration of 16 dSm-1, time of 17 days, and pH of 6.5. C. rossii's potential in removing 58% of Cd under the obtained optimum condition from the modelling was evaluated in real condition in the laboratory. The results revealed that around 56% of the initial added Cd concentration was removed by carpobrotus rossii. As a take home message, carpobrotus rossii can be recommended as an efficient plant to remove heavy metals especially cadmium from soil and sediments in arid area which have a salty soil.