Responses of the species complex Fallopia × bohemica to single-metal contaminations to Cd, Cr or Zn: growth traits, metal accumulation and secondary metabolism

Accumulation of metallic trace elements in Reynoutria japonica: a risk assessment for plant biomass valorization

“…When cultivated in controlled conditions (Cd range: 0.1–10 mg kg −1 , Cr range: 23.4–332 mg kg −1 , and Zn range: 42.9–924 mg Zn kg −1 ), other authors found evidence that the presence of MTE in soil has a low impact on Reynoutria spp. overall growth traits during rhizome regeneration, and has a rather stimulating effect on plant growth depending on pollution level, which may enhance their competitiveness in relation to other plant species (Barberis et al 2020 ; Michalet et al 2017 ). Indeed, according to these studies, Cr and to a lesser extent also Zn could stimulate the plant growth.…”

“…It is hypothesized that such a positive effect could be mediated by the production of secondary metabolites by R. japonica and reflect plant root interactions with rhizosperic microbes. Those molecules could be directly or indirectly involved in plant tolerance and adaptation to metallic stress (Barberis et al 2020 ; Michalet et al 2017 ).…”

“…To the best of the authors’ knowledge, only Michalet et al ( 2017 ) and Barberis et al ( 2020 ) previously investigated MTE transfer into R. japonica growing for three months in controlled conditions on freshly spiked soils with Cd (0.1–10 mg kg −1 ), Cr (9–440 mg kg −1 ), Pb (6–295 mg kg −1 ), and Zn (18–880 mg kg −1 ). If Barberis et al ( 2020 ) confirmed the very low BCFs for Cd (< 0.3), that for Zn reached 1.4. Besides, Michalet et al ( 2017 ) obtained Zn-BCF shoot between 0.5 and 0.8 and Cd-BCF shoot from 1 to 3.…”

“…Most of these articles reported that R. japonica seems able to accumulate MTE with the highest concentrations of metals in rhizome, whereas the uncontrolled conditions of such field studies did not allow to address to which extent the above-ground organs are supplied by MTE from the rhizome or from air borne contamination (Böhmová and Šoltés 2017 ). Suggestion of such a translocation of MTE from rhizome to above-ground organs was recently provided by two greenhouse-controlled conditions studies, but observations were limited to Cd, Cr, and Zn and for measurements on either a single (Barberis et al 2020 ) or triplicate (Michalet et al 2017 ) per treatment pooled samples of stem and leaf together. Therefore, further investigations in controlled conditions quantifying the transfer of MTE from soil to R. japonica below- and above-ground organs are needed.…”

Invasive Plants in Support of Urban Farming: Fermentation-Based Organic Fertilizer from Japanese Knotweed

“…A more mechanized approach could be applied for the larger condensed F. japonica patches that typically occur along the banks of highways, especially when the plants are mowed at least twice per year [64]. This would ensure a high green-mass yield and an interruption in the reproductive cycle of the plant (pollen drift and seed formation) at the stage when the plant N content is expected to be highest, although precaution is necessary as some metallic trace elements, such as Zn, can transport to aboveground parts of F. japonica [65]. The approach taken in this study seems to be able to complement frequent (weekly) management of F. japonica stands in parks, nurseries and riverbanks, where frequent cutting [11] continues to be applied as a means of suppressing F. japonica, although the long-term success of frequent mowing of F. japonica as a management method remains to be proven [66].…”