Bacterial communities associated with Brassica napus L. grown on trace element‐contaminated and non‐contaminated fields: a genotypic and phenotypic comparison

Abstract

SummaryCultivable bacterial strains associated with field-grown Brassica napus L. (soil, rhizosphere and roots) from a trace elements (Cd, Zn and Pb) contaminated field and a non-contaminated control field were characterized genotypically and phenotypically. Correspondence analysis of the genotypic data revealed a correlation between soil and rhizosphere communities isolated from the same field, indicating that local conditions play a more important role in influencing the composition of (rhizosphere) soil bacterial communities than root exudates. In contrast, endophytic communities of roots showed a correlation between fields, suggesting that plants on the two fields contain similar obligate endophytes derived from a common seed endophytic community and/or can select bacteria from the rhizosphere. The latter seemed not very likely since, despite the presence of several potential endophytic taxa in the rhizosphere, no significant correlation was found between root and rhizosphere communities. The majority of Cd/Zn tolerant strains capable of phosphorus solubilization, nitrogen fixation, indole-3-acetic acid production and showing 1-aminocyclopropane-1-carboxylate deaminase capacity were found in the rhizosphere and roots of plants growing on the contaminated field.

Phytoremediation of Metal Contaminated Soil Using Willow: Exploiting Plant-Associated Bacteria to Improve Biomass Production and Metal Uptake

“…previous investigations in our laboratory (Weyens et al 2013b;Croes et al 2013). Also the orders of magnitude of cultivable bacteria found in rhizosphere and roots correspond with abovementioned literature.…”

Beneficial endophytic microorganisms of Brassica – A review

“…Ecological studies indicate that the rhizosphere community structures of field grown B. napus can contain diverse groups of bacteria with the endophytic component composed of a subset of this rhizoplane community or with the obligate endophytes potentially derived from a common seed endophytic community (Croes et al, 2013;Germida et al, 1998). There are many reports of gram-positive bacteria, from groups such as the Actinobacteria (i.e.…”

Formulation of Novel Surface Sterilization Method and Culture Media for the Isolation of Endophytic Actinomycetes from Medicinal Plants and its Antibacterial Activity

“…Among endophytes, a distinction can be made between obligate endophytes [5] and facultative endophytes [6]. Obligate endophytes are expected to be the hardest to cultivate, since they require more specific conditions and therefore the main focus of this manuscript.…”