Molecular characterization of nitrogen fixing microsymbionts from root nodules of Vachellia (Acacia) jacquemontii, a native legume from the Thar Desert of India

Indu Singh Sankhla, Nisha Tak, Raju Ram Meghwal, Sunil Choudhary, Alkesh Tak, Sonam Rathi, Janet I. Sprent, Euan K. James (Lead / Corresponding author), Hukam Singh Gehlot (Lead / Corresponding author)

    Research output: Contribution to journalArticlepeer-review

    32 Citations (Scopus)


    Aims: To describe the structure of nodules of Vachellia (Acacia) jacquemontii, and to characterise the rhizobia that occupy them. 

    Methods: Light and electron microscopy were used to analyse nodules. Rhizobia were characterised using their 16S rRNA, housekeeping and symbiosis-related gene sequences. 

    Results: Nodules of V. jacquemontii were typical of all other described mimosoid legumes. All 73 of the isolates were strains of Ensifer, and concatenated phylogenetic analysis of their housekeeping genes (rrs, recA, atpD, glnII and dnaK) suggested that they are novel, forming separate lineages close to E. saheli. The phylogenies of the symbiosis-essential genes nodA and nifH were inconsistent with the housekeeping phylogenies. The nodA sequences of most isolates were close to that of E. arboris HAMBI 1552T, but the nifH gene was found to be related to that of E. kostiensis HAMBI 1489T. All the tested Ensifer strains, except for AJ24, were found to be capable of nodulating other species of Vachellia as well as native Indian Mimosa and Prosopis spp. 

    Conclusions: Stressful conditions caused by the alkaline soil of the Thar Desert have resulted in V. jacquemontii being nodulated by diverse and promiscuous Ensifer species that are capable of nodulating other native members of the tribe Mimoseae.

    Original languageEnglish
    Pages (from-to)21-40
    Number of pages20
    JournalPlant and Soil
    Issue number1
    Early online date29 Feb 2016
    Publication statusPublished - Jan 2017


    • Ensifer
    • Multi Locus Sequence Analysis (MLSA)
    • nifH
    • nodA
    • rhizobia
    • Thar Desert
    • Vachellia (Acacia) jacquemontii

    Fingerprint Dive into the research topics of 'Molecular characterization of nitrogen fixing microsymbionts from root nodules of <i>Vachellia (Acacia) jacquemontii</i>, a native legume from the Thar Desert of India'. Together they form a unique fingerprint.

    Cite this