Reaction norms of life history traits in response to zinc in Thlaspi caerulescens from metalliferous and nonmetalliferous sites

Abstract

Summary• We examined phenotypic plasticity of fitness components in response to zinc (Zn) in the Zn hyperaccumulator, Thlaspi caerulescens .• Two populations from Zn-enriched soils (M) and two populations from normal soils (NM) were grown in pots at three Zn concentrations (0, 1000 and 8000 mg kg − 1 Zn), for an entire life cycle. Growth, Zn accumulation and fitness components were assessed.• Based on vegetative growth, M and NM populations had similar Zn tolerance at 1000 mg kg − 1 Zn. However, reproductive output was markedly decreased in NM at 1000 and 8000 mg kg − 1 Zn. In M populations, Zn did not affect fitness. However, low Zn status enhanced reproductive output in year 1 compared with year 2 and decreased survival after the first flowering season.• M populations are able to achieve equal fitness across a broad range of Zn concentrations in soil by different combinations of fecundity and longevity. No cost of higher tolerance was demonstrated in M populations. Reproductive traits appeared to be a more sensitive indicator of tolerance than vegetative growth.

Phytoremediation of urban soils contaminated with trace metals using Noccaea caerulescens: comparing non-metallicolous populations to the metallicolous ‘Ganges’ in field trials

“…However, there might be a threshold concentration above which Zn no longer stimulates plant growth as suggested by the negative correlation between plant Zn uptake and exchangeable concentration in the soil at GR (only significant for NMET plants). Such negative effect has already been observed at high and very high Zn concentrations (1000 and 8000 mg kg −1 ) (Dechamps et al 2007). Nevertheless, for NMET plants only, the adverse effect of increasing Zn concentrations at GR might be linked to the jointly increasing Pb concentrations up to a potentially toxic level (on average 400-500 mg kg −1 total Pb on both sites, up to 3000 mg kg −1 ).…”

“…CAL and NMET ecotypes have different metal-related traits. When grown in the same substrate, NMET accumulate more Zn (about twice) and Ni than CAL (Escarré et al 2000;Meerts and van Isacker 1997), and NMET can reach 20,000 μg g −1 of Zn on moderately contaminated substrates (Dechamps et al 2007). On the other hand, high Cd CAL populations from South of France (such as Saint-Félix or Ganges) have been identified for their great potential of Cd phytoextraction, as they can accumulate up to 1000 μg g −1 (Hammer and Keller 2003;Lombi et al 2001;Robinson et al 1998;Zhao et al 2003), compared to 300 μg g −1 for NMET .…”

Metal concentration and metal mass of metallicolous, non metallicolous and serpentine Noccaea caerulescens populations, cultivated in different growth media

“…Overall, SERP populations (and particularly PW) had low biomass values but the highest Zn concentrations, followed by NMET and MET. Several studies comparing MET and NMET populations showed that NMET have higher Zn concentration capacities than MET (Meerts and Van Isacker 1997;Escarré et al 2000;Meerts et al 2003;Dechamps et al 2007), which was accounted for by the need for N. caerulescens growing on Zn-poor soil to compensate for the low Zn availability in their natural environment (Meerts and Van Isacker 1997). The results of this study suggest that SERP populations behave like NMET with huge capacities of foliar Zn concentration.…”

“…Interestingly, NMET individuals usually accumulate more Zn than MET plants when grown in the same soil (e.g. Meerts and Van Isacker 1997;Escarré et al 2000;Meerts et al 2003;Dechamps et al 2007). Serpentine populations (SERP), that have been less studied, can also accumulate Zn even with low extractable soil Zn concentrations (Peer et al 2003).…”

“…Meerts and Van Isacker 1997;Escarré et al 2000;Lombi et al 2001a). In addition, experimental studies comparing MET with NMET populations simultaneously are scarce and were mostly conducted by Belgian and French teams (Meerts and Van Isacker 1997;Escarré et al 2000;Meerts et al 2003;Noret et al 2005Dechamps et al 2007Dechamps et al , 2008b, and even less common are studies that compared populations from metal-contaminated and serpentine soils (Peer et al 2003;Roosens et al 2003). Only two studies (Assunção et al 2003a; compared one population of each of the three origins.…”