TY - JOUR

T1 - Rhizobial Microsymbionts of Kamchatka Oxytropis Species Possess Genes of the Type III and VI Secretion Systems, Which Can Affect the Development of Symbiosis

AU - Safronova, Vera I.

AU - Guro, Polina V.

AU - Sazanova, Anna L.

AU - Kuznetsova, Irina G.

AU - Belimov, Andrey A.

AU - Yakubov, Valentin V.

AU - Chirak, Elizaveta R.

AU - Afonin, Alexey M.

AU - Gogolev, Yuri V.

AU - Andronov, Evgeny E.

AU - Tikhonovich, Igor A.

N1 - Publisher Copyright: © 2020 The American Phytopathological Society

PY - 2020/10

Y1 - 2020/10

N2 - A collection of rhizobial strains isolated from root nodules of the narrowly endemic legume species Oxytropis erecta, O. anadyrensis, O. kamtschatica, and O. pumilio originating from the Kamchatka Peninsula (Russian Federation) was obtained. Analysis of the 16S ribosomal RNA gene sequence showed a significant diversity of isolates belonging to families Rhizobiaceae (genus Rhizobium), Phyllobacteriaceae (genera Mesorhizobium, Phyllobacterium), and Bradyrhizobiaceae (genera Bosea, Tardiphaga). A plant nodulation assay showed that only strains belonging to genus Mesorhizobium could form nitrogen-fixing nodules on Oxytropis plants. The strains M. loti 582 and M. huakuii 583, in addition to symbiotic clusters, possessed genes of the type III and type VI secretion systems (T3SS and T6SS, respectively), which can influence the host specificity of strains. These strains formed nodules of two types (elongated and rounded) on O. kamtschatica roots. We suggest this phenomenon may result from Nod factor–dependent and –independent nodulation strategies. The obtained strains are of interest for further study of the T3SS and T6SS gene function and their role in the development of rhizobium-legume symbiosis. The prospects of using rhizobia having both gene systems related to symbiotic and nonsymbiotic nodulation strategies to enhance the efficiency of plant-microbe interactions by expanding the host specificity and increasing nodulation efficiency are discussed.

AB - A collection of rhizobial strains isolated from root nodules of the narrowly endemic legume species Oxytropis erecta, O. anadyrensis, O. kamtschatica, and O. pumilio originating from the Kamchatka Peninsula (Russian Federation) was obtained. Analysis of the 16S ribosomal RNA gene sequence showed a significant diversity of isolates belonging to families Rhizobiaceae (genus Rhizobium), Phyllobacteriaceae (genera Mesorhizobium, Phyllobacterium), and Bradyrhizobiaceae (genera Bosea, Tardiphaga). A plant nodulation assay showed that only strains belonging to genus Mesorhizobium could form nitrogen-fixing nodules on Oxytropis plants. The strains M. loti 582 and M. huakuii 583, in addition to symbiotic clusters, possessed genes of the type III and type VI secretion systems (T3SS and T6SS, respectively), which can influence the host specificity of strains. These strains formed nodules of two types (elongated and rounded) on O. kamtschatica roots. We suggest this phenomenon may result from Nod factor–dependent and –independent nodulation strategies. The obtained strains are of interest for further study of the T3SS and T6SS gene function and their role in the development of rhizobium-legume symbiosis. The prospects of using rhizobia having both gene systems related to symbiotic and nonsymbiotic nodulation strategies to enhance the efficiency of plant-microbe interactions by expanding the host specificity and increasing nodulation efficiency are discussed.

KW - Kamchatka region

KW - Oxytropis spp

KW - Plant-microbe interaction

KW - Symbiosis

KW - T3SS

KW - T6SS

UR - https://apsjournals.apsnet.org/doi/10.1094/MPMI-05-20-0114-R

UR - http://www.scopus.com/inward/record.url?scp=85091956885&partnerID=8YFLogxK

U2 - 10.1094/MPMI-05-20-0114-R

DO - 10.1094/MPMI-05-20-0114-R

M3 - Article

VL - 33

SP - 1232

EP - 1241

JO - Molecular Plant-Microbe Interactions

JF - Molecular Plant-Microbe Interactions

SN - 0894-0282

IS - 10

ER -