%0 Journal Article %A Reinhold, Barbara %A Hurek, Thomas %A Fendrik, Istvan %A Pot, Bruno %A Gillis, Monique %A Kersters, Karel %A Thielemans, Stefaan %A De Ley, Jozef %T Azospirillum halopraeferens sp. nov., a Nitrogen-Fixing Organism Associated with Roots of Kallar Grass (Leptochloa fusca (L.) Kunth) %D 1987 %J International Journal of Systematic and Evolutionary Microbiology, %V 37 %N 1 %P 43-51 %@ 1466-5034 %R https://doi.org/10.1099/00207713-37-1-43 %I Microbiology Society, %X Among the nitrogen-fixing bacteria associated with the roots of Leptochloa fusca (L.) Kunth in salt-affected soils in the Punjab region of Pakistan, we found a homogeneous group of eight diazotrophs. Cells are vibrioid to S shaped, are motile by one polar flagellum, and produce granules of poly-β-hydroxybutyrate. They have a respiratory type of metabolism, show microaerophilic growth when fixing nitrogen, grow well on salts of organic acids, and can also use fructose and mannitol. On nitrogen-free semisolid media, they require biotin, utilize mannitol, but not glucose or sucrose, and cannot acidify glucose aerobically or anaerobically. Optimal growth occurs at 0.25% NaCl and 41°C. Deoxyribonucleic acid (DNA)-ribosomal ribonucleic acid (rRNA) hybridizations show that the organisms belong to the Azospirillum rRNA branch, where they cluster together with Azospirillum amazonense. They form a phenotypically and protein electrophoretically homogeneous group of bacteria, clearly distinct from Azospirillum amazonense, Azospirillum lipoferum, and Azospirillum brasilense. As no DNA-DNA binding was found with any of the three Azospirillum species, we propose a fourth Azospirillum species for this group of isolates. Because of better growth at increased NaCl concentrations, we named the new species Azospirillum halopraeferens. Strain Au 4 (= LMG 7108) is the type strain, which has been deposited at the Deutsche Sammlung von Mikroorganismen, Göttingen, Federal Republic of Germany, as DSM 3675. %U https://www.microbiologyresearch.org/content/journal/ijsem/10.1099/00207713-37-1-43