Isolation and characterization of dark septate endophytes: towards their use in the phytomanagement of metal-contaminated sites?
Abstract
Phytomanagement can be used to reduce the dispersion of trace elements (TE) in the environment. It
provides ecosystem services and is economically attractive through the production of non edible biomass
(Chalot et al., 2012). However, phytomanagement could face limitations in TE-contaminated sites, such as
slow plant growth due to TE phytotoxicity (Mench et al., 2010). To overcome this problem, microorganisms
can be used to favor both plant establishment and growth. Among these microorganisms, dark septate
endophytes (DSE) are fungi that are abundant in TE-contaminated soils and are usually resistant to TE (Ban
et al., 2012; Regvar et al., 2010). They may benefit their host plants by facilitating the uptake of nutrients
and by limiting metal toxicity (Likar & Regvar, 2013; Newsham, 2011). These results prompted us to select
DSE for future phytomanagement trials. For this purpose, DSE were isolated from roots of trees growing
on TE-contaminated soils and we characterised their plant growth promotion (PGP) potential in vitro.
Moreover, the PGP activity was tested with inoculated plants growing in TE-contaminated soils.