两个杂交饲用大豆的根瘤菌生物功能与共生匹配性OA北大核心CSTPCD

Hybrid feed soybean rhizobia have potential biological functions and symbiotic compatibility,to comprehensively evaluate and screen the best matching strain,the hybrid offspring of wild soybean and cultivated soybean"Mengnong S006 forage soybean"(S006)and strain"8-4-1 brown"(8-4-1)were used as materials.The rhizobia were isolated and purified at the branching stage in the experimental planting areas of Hohhot and Tongliao.After BOX-PCR classification and 16S rDNA amplification and sequencing,14 strains of rhizobia were obtained and named respectively.They belong to Sinorhizobium,Rhizobium and Neorhizobium.The phosphate solubilizing ability and auxin secretion ability of the obtained strains were determined by phosphate solubilizing circle method,molybdenum antimony anti-colorimetric method and Salkowski colorimetric method.The results showed that 14 rhizobia had phosphate solubilizing ability and auxin secretion ability.Among them,the strain Z8 had the strongest phosphate solubilizing ability,and the phosphate solubilizing capacity was 4.55 mg·L-1.The strain S133 with the highest auxin secretion was 224.16 mg·L-1.Under the condition of indoor pot culture,the obtained strains were inoculated with the experimental materials respectively,and the symbiotic matching status was observed,with no inoculation as the control.After 25 days of inoculation with rhizobia,the aboveground fresh weight,aboveground dry weight,plant height,nodule number,nodule fresh weight,leaf number,nitrogenase activity and total nitrogen content of hybrid forage soybean were measured.Through the comprehensive evaluation of the membership function,the top three strains of S006 symbiotic matching effect were Z8,Z2 and S134.The top three strains of 8-4-1 were Z75,S134 and Z2.In this study,strains with excellent symbiotic matching effect with two hybrid forage soybeans were screened.In order to make rhizobium inoculation agent,when planting two hybrid forage soybeans in Inner Mongolia,give full play to the nitrogen fixation of excellent rhizobium,reduce the amount of chemical fertilizer application,and provide strain resources for further research.