Life history traits of the pseudometallophyte Thlaspi caerulescens in natural populations from Northern Europe

Abstract

We examined recruitment, survival, life cycle and fecundity of two metallicolous (M, on metalliferous calamine soils) and two non‐metallicolous (NM, on normal soils) populations of Thlaspi caerulescens in Belgium and Luxemburg. In each population, permanent plots were monitored over two reproductive seasons. In M populations, plots were located in two contrasting environments (grass versus grove) in order to test the influence of vegetation cover on life strategy. Our results show that the monocarpic life cycle is dominant in all populations of T. caerulescens. However the length of the pre‐reproductive period varies from several months (winter annuals) to 1 year or more (perennials), and is partly related to plant origin (M versus NM). Most plants growing in metalliferous environments were annuals, whereas NM plants were mostly perennials. These differences in life cycle were related to differences in survival during summer, which was better in NM than in M populations. Within each M population, different survival conditions and life cycles were observed according to vegetation cover. Plants growing in grass areas were mostly annuals and had a low survival rate in summer whereas grove plants were mostly perennials and survived better in summer. Our results suggest the selection of stress avoiders (shortening of life cycle) in M populations of T. caerulescens but only for individuals growing in grass areas. Summer survival seems to play a key role in selection of life strategy in T. caerulescens.

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

“…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 . Furthermore, life history traits of N. caerulescens differ according to the geographic origin and among ecotypes: NMET populations from Luxemburg are mostly short-lived monocarpic perennials while CAL from South of France are in general winter annuals (Dechamps et al 2011;Jiménez-Ambriz et al 2007). Lastly, CAL populations are less adapted to herbivore attacks than NMET as they exhibit lower levels of chemical defenses (e.g., lower glucosinolate concentrations) (Noret et al 2005.…”

“…Secondly, our results show a tendency for NMET plants to produce greater individual biomass (at GR, 1.5 times more than GAN). This might be explained by the difference of dominant natural life cycle of the two ecotypes: annual for CAL (GAN) while NMET from Luxemburg are mostly short-lived perennials (Dubois 2005;Dechamps et al 2011). With a longer vegetative growth prior to flowering, NMET from Luxemburg may therefore have an advantage in terms of biomass production.…”

Taxonomy and systematics are key to biological information: Arabidopsis, Eutrema (Thellungiella), Noccaea and Schrenkiella (Brassicaceae) as examples

“…A more comprehensive study based on isozyme analysis and focusing on various populations of Noccaea caerulescens and N. brachypetala from contaminated and non-contaminated sites was presented later (Koch et al, 1998) demonstrating that the N. caerulescens ecotype accumulating metals might have evolved several times independently. There is also increasing ecological knowledge of the various populations of N. caerulescens , and it has been shown, for example, that there are significant differences in life-history traits (Macnair, 2007; Dechamps et al, 2011), in outcrossing rates (Koch et al, 1998; Duboix et al, 2003), or in the strength of natural selection limiting gene flow between metalliferous and non-metalliferous locations (Besnard et al, 2009). …”

Copper and arsenic accumulation of Pityrogramma calomelanos, Nephrolepis biserrata, and Cynodon dactylon in Cu- and Au- mine tailings

“…Obligate metallophytes cannot live outside their natural geographical distribution while facultative can grow outside their natural distribution range (Baker et al, 2010). In general, pseudo-metallophytes are species that are not native on natural metalliferous soils and can thrive on both metalliferous and normal soils (Dechamps et al, 2011). Further, various groupings are made depending on the metal that the metallophytes absorb.…”