RESUMEN
The current work aims to investigate the influence of fertilization (fertilizer) and fungal inoculation (Funneliformis mosseae and Serendipita indica (formerly Piriformospora indica), respectively arbuscular mycorrhizal (AMF) and endophytic fungi) on the phytoextraction potential of Arabidopsis halleri (L.) O'Kane & Al-Shehbaz (biomass yield and/or aboveground part Zn and Cd concentrations) over one life plant cycle. The mycorrhizal rates of A. halleri were measured in situ while the fungal inoculation experiments were carried out under controlled conditions. For the first time, it is demonstrated that the fertilizer used on A. halleri increased its biomass not only at the rosette stage but also at the flowering and fruiting stages. Fertilizer reduced the Zn concentration variability between developmental stages and increased the Cd concentration at fruiting stage. A. halleri roots did not show AMF colonization at any stage in our field conditions, neither in the absence nor in the presence of fertilizer, thus suggesting that A. halleri is not naturally mycorrhizal. Induced mycorrhization agreed with this result. However, S. indica has been shown to successfully colonize A. halleri roots under controlled conditions. This study confirms the benefit of using fertilizer to increase the phytoextraction potential of A. halleri. Overall, these results contribute to the future applicability of A. halleri in a phytomanagement strategy by giving information on its cultural itinerary.
Asunto(s)
Arabidopsis , Micorrizas , Contaminantes del Suelo , Biomasa , Cadmio/análisis , Fertilización , Micorrizas/fisiología , Raíces de Plantas , Contaminantes del Suelo/análisis , ZincRESUMEN
The phytoextraction potential of Arabidopsis halleri (L.) O'Kane & Al Shehbaz and Salix viminalis L. to partially remove Zn and Cd in soil was investigated. In an urban field site, a very short rotation coppice of willows was implemented, and growth parameters were monitored for 3 years. A. halleri was cultivated in the same site with or without fertilizer to improve biomass yield and/or Zn and Cd aerial part concentrations. Effects of harvest and co-cultivation on these two parameters were measured. To determine if willows and A. halleri leaves were risky in case of consumption by a herbivorous invertebrate like the landsnail Cantareus aspersus, metal concentrations of snails fed with Zn- and Cd-enriched and low enriched leaves were compared. Willows and A. halleri grew well on the metal-contaminated soil (1.7 and 616 mg kg-1 Cd and Zn, respectively). The A. halleri Zn foliar concentration reached the Zn hyperaccumulation threshold (> 10,000 mg kg-1 DW) in the presence of NPK fertilizer and although the soil was alkaline (pH > 8.2). Cd concentration increased with harvest and fertilizer. Cd and Zn foliar concentrations of willows were far above baseline values. Laboratory snails exposure revealed that willow leaves ingestion caused a moderate increase of Cd, Pb, and Zn bioaccumulation in snails compared to the one caused by A. halleri ingestion. The soil and plant metal concentrations were reflected by field snail biomonitoring. This study confirmed the interest of selecting A. halleri and willows to partially remove Zn and Cd in the soil and emphasized their potential usefulness in greening urban contaminated area and producing raw materials for green chemistry while paying attention to the environmental pollutant transfer.