Arbuscular mycorrhiza partially protect chicory roots against oxidative stress induced by two fungicides, fenpropimorph and fenhexamid

Abstract

The present work examined the oxidative stress induced by different concentrations (0.02 and 0.2 mg l-1) of two sterol biosynthesis inhibitor fungicides (fenpropimorph and fenhexamid) in non-target chicory root colonised or not by Glomus intraradices in a monoxenic system. The fungicides were found to cause oxidative damage by increasing lipid peroxidation measured by malondialdehyde production in non-colonised roots. Detoxification of the H(2)O(2) product was measured at 0.2 mg l-1 of fenpropimorph by an increase in peroxidase activities suggesting an antioxidant capacity in these roots. Moreover, this study pointed out the ability of arbuscular mycorrhiza to alleviate partially the oxidative stress in chicory roots, probably by lowering reactive oxygen species concentrations, resulting from increases in antioxidant defences. Our results suggest that the enhanced fungicide tolerance in the AM symbiosis could be related to less cell membrane damage.

Characterization of a CuZn superoxide dismutase gene in the arbuscular mycorrhizal fungus Glomus intraradices

“…These data suggest that antifungal effects of this SBI fungicide might not be only due to the interference with sterol metabolism, as recently described by Campagnac et al (2009) and Oger et al (2009), but also to the perturbation of other biological circuits within the fungal cells and suggest that ROS production and scavenging are involved in the response to SBI. Interestingly, G. intraradices colonization was shown to partially protect roots from oxidative stress induced by fenpropimorph (Campagnac et al 2010). It is tempting to speculate that fungal antioxidant activities, including GintSOD1, may play a role in this protective effect.…”

Propiconazole Toxicity on the Non-Target Organism, the Arbuscular Mycorrhizal Fungus, Glomus irregulare

“…These extracts were evaporated under N 2 and transferred to chromatography vials. FA methyl esters were analysed as described in Campagnac et al (2010) using a PerkinElmer Autosystem gas chromatograph (GC) equipped with a flame-ionisation detector (Norwalk, CT, USA) and a ECTM-1000 (Alltech Associates Inc., Deerfield, IL, USA) capillary column (30 m x 0.53 mm i.d.) with hydrogen as carrier gas (3.6 mL.min −1 ).…”

“…The in vitro cultures allow non-destructive observations of AMF (Fortin et al, 2002), they are standardized and reproducible method enabling comparisons of various molecules impact on AMF (Debiane et al, 2008(Debiane et al, , 2009Hillis et al, 2008;Zocco et al, 2008;Campagnac et al, 2010). In addition, thanks to these monoxenic cultures, big amounts of biological material free of contaminant microorganisms can be obtained.…”

“…In addition, thanks to these monoxenic cultures, big amounts of biological material free of contaminant microorganisms can be obtained. Zocco et al (2008) and Campagnac et al (2008Campagnac et al ( , 2009Campagnac et al ( , 2010 studied the effects of two SBI fungicides, i.e. fenpropimorph and fenhexamid on AMF and root development.…”

“…Fenpropimorph was also underscored by the significant reduction in root growth and appeared to be due to (i) the replacement of the normal Δ5-sterols by unusual sterols: 9 ,19-cyclopropylsterols, Δ8,14-stérols, Δ8-sterols and Δ7-sterols (ii) and the induction of an oxidative stress (lipid peroxidation, antioxidant enzyme activities). However no impact on the sterol profile and root development was detected with fenhexamid (Campagnac et al, 2008), while a significant oxidative stress was highlighted in roots (Campagnac et al, 2010). Indeed, when plants are subjected to environmental stresses, as SBI fungicides, reactive oxygen species (ROS) are produced, such as superoxide radical (O 2 .-), hydroxyl radical ( .…”