Curing of symbiotic plasmid of <i>Mesorhizobium huakuii subsp. rengei</i> isolated <span style="font-size:14.0pt;line-height:115%;font-family:"Times New Roman"; mso-fareast-font-family:"Times New Roman";color:#1D1D1D;mso-ansi-language:EN-IN; mso-fareast-language:EN-IN;mso-bidi-language:HI" lang="EN-IN">from <i>Astragalus sinicus</i></span>

Abstract

<i><span style="font-size:14.0pt;line-height: 115%;font-family:" times="" new="" roman";mso-fareast-font-family:"times="" roman";="" color:#1d1d1d;mso-ansi-language:en-in;mso-fareast-language:en-in;mso-bidi-language:="" hi"="" lang="EN-IN">Astragalus sinicus</span></i><span style="font-size:14.0pt; line-height:115%;font-family:" times="" new="" roman";mso-fareast-font-family:"times="" roman";="" color:#1d1d1d;mso-ansi-language:en-in;mso-fareast-language:en-in;mso-bidi-language:="" hi"="" lang="EN-IN"> (Chinese Milk vetch), a green manure leguminous plant, harbors <i>Mesorhizobium huakuii</i> subsp. <i>rengei</i> strain B3 in the root nodules. The visualization of symbiotic plasmid of strain B3 showed the presence of one <i>sym</i> plasmid of about 425 kbp. Curing of <i>sym</i> plasmid by temperature and acrydine orange was studied. Growing rhizobial cells at high temperature (37°C) or treating the cells with acrydine orange at 50 mg/I eliminated <i>sym </i>plasmid of <i>M.</i> <i>huakuii </i>strain B3, which was confirmed by <i>sym</i> plasmid visualization and plant infection test of cured strains.</span>