Genetic diversity and distribution of rhizobia associated with the medicinal legumes Astragalus spp. and Hedysarum polybotrys in agricultural soils

Yan, Hui; Ji, Zhao; Jiao, Yin; Wang, En Tao; Chen, Wen Feng; Guo, Baoyuan; Chen, Wen Xin

doi:10.1016/j.syapm.2016.01.004

Cited by 24 publications

(14 citation statements)

References 44 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…In the absence of pollutants, nonmining sites also display distinct mesorhizobial lineages that, although not significant here, might be impacted by nutrientbased parameters, notably soil organic carbon and nitrogen contents. This may influence the mesorhizobial diversity distribution, as found for mesorhizobia from legumes grown in barren or rich soil fields (49). The results of our study demonstrated that heavy metal levels strongly affected rhizobial diversity by selecting different genospecies, in contrast to results of previous studies that showed no effect of heavy metals on the rhizobial species diversity (23,50).…”

Section: Discussioncontrasting

confidence: 80%

Ancient Heavy Metal Contamination in Soils as a Driver of Tolerant Anthyllis vulneraria Rhizobial Communities

Mohamad

Maynaud

Quéré

et al. 2017

Appl Environ Microbiol

View full text Add to dashboard Cite

Anthyllis vulneraria is a legume associated with nitrogen-fixing rhizobia that together offer an adapted biological material for mine-soil phytostabilization by limiting metal pollution. To find rhizobia associated with Anthyllis at a given site, we evaluated the genetic and phenotypic properties of a collection of 137 rhizobia recovered from soils presenting contrasting metal levels. Zn-Pb mine soils largely contained metal-tolerant rhizobia belonging to Mesorhizobium metallidurans or to another sister metal-tolerant species. All of the metal-tolerant isolates harbored the cadA marker gene (encoding a metal-efflux P IB -type ATPase transporter). In contrast, metalsensitive strains were taxonomically distinct from metal-tolerant populations and consisted of new Mesorhizobium genospecies. Based on the symbiotic nodA marker, the populations comprise two symbiovar assemblages (potentially related to Anthyllis or Lotus host preferences) according to soil geographic locations but independently of metal content. Multivariate analysis showed that soil Pb and Cd concentrations differentially impacted the rhizobial communities and that a rhizobial community found in one geographically distant site was highly divergent from the others. In conclusion, heavy metal levels in soils drive the taxonomic composition of Anthyllis-associated rhizobial populations according to their metal-tolerance phenotype but not their symbiotic nodA diversity. In addition to heavy metals, local soil physicochemical and topoclimatic conditions also impact the rhizobial beta diversity. Mesorhizobium communities were locally adapted and site specific, and their use is recommended for the success of phytostabilization strategies based on Mesorhizobium-legume vegetation.IMPORTANCE Phytostabilization of toxic mine spoils limits heavy metal dispersion and environmental pollution by establishing a sustainable plant cover. This ecofriendly method is facilitated by the use of selected and adapted cover crop legumes living in symbiosis with rhizobia that can stimulate plant growth naturally through biological nitrogen fixation. We studied microsymbiont partners of a metaltolerant legume, Anthyllis vulneraria, which is tolerant to very highly metal-polluted soils in mining and nonmining sites. Site-specific rhizobial communities were linked to taxonomic composition and metal tolerance capacity. The rhizobial species Mesorhizobium metallidurans was dominant in all Zn-Pb mines but one. It was not detected in unpolluted sites where other distinct Mesorhizobium species occur. Given the different soil conditions at the respective mining sites, including their heavymetal contamination, revegetation strategies based on rhizobia adapting to local conditions are more likely to succeed over the long term compared to strategies based on introducing less-well-adapted strains.

show abstract

Section: Discussioncontrasting

confidence: 80%

Ancient Heavy Metal Contamination in Soils as a Driver of Tolerant Anthyllis vulneraria Rhizobial Communities

Mohamad

Maynaud

Quéré

et al. 2017

Appl Environ Microbiol

View full text Add to dashboard Cite

show abstract

“…Rhizobial strains isolated from root nodules of species of the genus Astragalus were always classified into the genera Mesorhizobium, Rhizobium or Sinorhizobium (Yan et al, 2016;Zhao et al, 2008). During a survey of rhizobia of the medicinal legume Astragalus mongholicus grown in an agricultusral field in Bozhou County, Anhui Province of China, three rhizobial strains (CCBAU 23380 T , CCBAU 23381 and CCBAU 23386) were isolated from the root nodules of this legume.…”

mentioning

confidence: 99%

Ensifer glycinis sp. nov., a rhizobial species associated with species of the genus Glycine

Yan

Sui

et al. 2016

International Journal of Systematic and Evolutionary Microbiology

Self Cite

View full text Add to dashboard Cite

Rhizobial strains from root nodules of Astragalus mongholicus and soybean (Glycine max) were characterized phylogenetically as members of the genus Ensifer (formerly named Sinorhizobium), based on 16S rRNA gene sequence comparisons. Results based upon concatenated sequence analysis of three housekeeping genes (recA, atpD and glnII, 93.8 % similarities to known species) and average nucleotide identity (ANI) values of whole genome sequence comparisons (ranging from 89.6 % to 83.4 % to Ensifer fredii and Ensifer saheli, respectively) indicated the distinct positions of these novel strains within the genus Ensifer. Phylogeny of symbiotic genes (nodC and nifH) of three novel strains clustered them with rhizobial species Ensifer fredii and Ensifer sojae, both isolated from nodules of Glycine max. Cross-nodulation tests showed that the representative strain CCBAU 23380 T could form root nodules with nitrogen fixation capability on Glycine soja, Albizia julibrissin, Vigna unguiculata and Cajanus cajan, but failed to nodulate Astragalus mongholicus, its original host legume. Strain CCBAU 23380 T formed inefficient nodules on G. max, and it did not contain 18 : 0, 18 : 1!7c 11-methyl or summed feature 1 fatty acids, which differed from other related strains. Failure to utilize malonic acid as a carbon source distinguished strain CCBAU 23380 T from the type strains of related species. The genome size of CCBAU 23380 T was 6.0 Mbp, comprising 5624 predicted genes with DNA G+C content of 62.4 mol%. Based on the results above, a novel species, Ensifer glycinis sp. nov., is proposed, with CCBAU 23380 T (=LMG 29231 T =HAMBI 3645 T ) as the type strain.

show abstract

“…Based on their tremendously important medicinal values and remarkable sand-fixing effects, Astragalus and Caragana species (belonging to Tribe Galegeae and Tribe Hydesareae, respectively) are widely cultivated in the northwest region of China. The diversity of rhizobia associated with these plants has been extensively studied (Zhao et al, 2008 ; Li et al, 2012 ; Yan et al, 2016 ). Previous researches revealed that both the cultivated and wild AC plants mainly nodulate with Mesorhizobium strains, while strains from other rhizobial genera occupied minor proportion in the nodules (Zhao et al, 2008 ; Lu et al, 2009 ; Li et al, 2012 ; Yan et al, 2016 ).…”

Section: Introductionmentioning

confidence: 99%

“…The diversity of rhizobia associated with these plants has been extensively studied (Zhao et al, 2008 ; Li et al, 2012 ; Yan et al, 2016 ). Previous researches revealed that both the cultivated and wild AC plants mainly nodulate with Mesorhizobium strains, while strains from other rhizobial genera occupied minor proportion in the nodules (Zhao et al, 2008 ; Lu et al, 2009 ; Li et al, 2012 ; Yan et al, 2016 ). However, an exception was found in a previous study in our laboratory that strain R. yanglingense CCBAU01603 has a more competitive nodulation ability than the representatives of Mesorhizobium species ( M. silamurunense CCBAU01550, M. silamurunense CCBAU45272, M. septentrionale CCBAU01583, M. amorphae CCBAU01570, M. caraganae CCBAU01502) when Caragana plants were grown in sterile vermiculite (Ji et al, 2017 ).…”

Section: Introductionmentioning

confidence: 99%

“…The major symbiotic rhizobia nodulating AC hosts were Mesorhizobium strains (Lu et al, 2009 ; Li et al, 2012 ; Yan et al, 2016 ) harboring conserved nodC genes differed from those in non-AC-nodulating strains, while the nodC of AC symbiotic strain R. yanglingense CCBAU01603 was not clustered closely to the AC-nodulating Mesorhizobium strains. Since nodC gene is an important determinant of chitin oligosaccharide chain of Nod factor that is a contributor to host specificity according to the study on Sinorhizobium (former Rhizobium ) meliloti (Kamst et al, 1997 ), the same preference of nodulation with AC plants by R. yanglingense CCBAU01603 and the Mesorhizobium strains might be determined by other symbiotic genes.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Evolutionarily Conserved nodE, nodO, T1SS, and Hydrogenase System in Rhizobia of Astragalus membranaceus and Caragana intermedia

Yan

Xie

et al. 2017

Front. Microbiol.

Self Cite

View full text Add to dashboard Cite

Mesorhizobium species are the main microsymbionts associated with the medicinal or sand-fixation plants Astragalus membranaceus and Caragana intermedia (AC) in temperate regions of China, while all the Mesorhizobium strains isolated from each of these plants could nodulate both of them. However, Rhizobium yanglingense strain CCBAU01603 could nodulate AC plants and it's a high efficiency symbiotic and competitive strain with Caragana. Therefore, the common features shared by these symbiotic rhizobia in genera of Mesorhizobium and Rhizobium still remained undiscovered. In order to study the genomic background influencing the host preference of these AC symbiotic strains, the whole genomes of two (M. silamurunense CCBAU01550, M. silamurunense CCBAU45272) and five representative strains (M. septentrionale CCBAU01583, M. amorphae CCBAU01570, M. caraganae CCBAU01502, M. temperatum CCBAU01399, and R. yanglingense CCBAU01603) originally isolated from AC plants were sequenced, respectively. As results, type III secretion systems (T3SS) of AC rhizobia evolved in an irregular pattern, while an evolutionarily specific region including nodE, nodO, T1SS, and a hydrogenase system was detected to be conserved in all these AC rhizobia. Moreover, nodO was verified to be prevalently distributed in other AC rhizobia and was presumed as a factor affecting the nodule formation process. In conclusion, this research interpreted the multifactorial features of the AC rhizobia that may be associated with their host specificity at cross-nodulation group, including nodE, nodZ, T1SS as the possible main determinants; and nodO, hydrogenase system, and T3SS as factors regulating the bacteroid formation or nitrogen fixation efficiency.

show abstract

Genetic diversity and distribution of rhizobia associated with the medicinal legumes Astragalus spp. and Hedysarum polybotrys in agricultural soils

Cited by 24 publications

References 44 publications

Ancient Heavy Metal Contamination in Soils as a Driver of Tolerant Anthyllis vulneraria Rhizobial Communities

Ancient Heavy Metal Contamination in Soils as a Driver of Tolerant Anthyllis vulneraria Rhizobial Communities

Ensifer glycinis sp. nov., a rhizobial species associated with species of the genus Glycine

Evolutionarily Conserved nodE, nodO, T1SS, and Hydrogenase System in Rhizobia of Astragalus membranaceus and Caragana intermedia

Contact Info

Product

Resources

About