解磷菌和根瘤菌复合接种对大豆和紫云英共生固氮的影响

从大豆根际及根瘤中分离获得2株具有较高解磷能力的细菌PSB-1和HZP1,通过Salkowski比色法和钼锑钪比色法,对这2个菌株产生IAA(indole-3-acetic acid,IAA)的能力和溶解无机磷的能力进行了测定,同时对紫云英和大豆进行接种,并对田间栽培的大豆进行了菌剂接种试验。结果显示:PSB-1及HZP1均具有解磷及产IAA的特性;单接种解磷菌HZP1或PSB-1均有促进紫云英和大豆生长的作用;相比于单接种根瘤菌,将这2株解磷细菌分别与根瘤菌混合接种能进一步提高大豆和紫云英的地上生物量、根瘤鲜质量和根瘤数。田间试验结果显示,单独接种根瘤菌剂或解磷菌剂都有一定的增产效果,但双接种根瘤菌剂和解磷菌剂的增产效果不明显。

Effects of co-inoculation of phosphate-solubilizing bacteria and rhizobium on symbiotic nitrogen fixation of soybean and Astragalus sinensis

Two phosphate solubilizing bacterial strains,PSB-1 and HZP1,were isolated form soybean nodules and rhizosphere soil. The ability of these two strains to produce IAA (indole-3-acetic acid IAA) and the ability to dissolve inorganic phosphorus were measured by Salkowski colorimetry and molybdenum antimony-phosphonium colorimetry. Soybean and Astragalus sinensis were co-inoculated. Results showed that both two phosphate solubilizing strain produced IAA. The legume growth-promoting effects of the phosphate solubilizing strains and rhizobium inoculum were investigated in unsterilized soil and soybean planting field. Inoculation with HZP1 or PSB-1 promoted the growth of Astragalus sinensis and soybean. Co-inoculation of phosphorus-solubilizing strains with rhizobium further increased the shoot biomass,fresh weight of nodules and the number of nodules of soybean and Astragalus sinensis. The results of field tests showed that inoculation with rhizobium or phosphate dissolving agents alone had a certain effect of increasing yield but double inoculation with rhizobium and phosphate dissolving bacteria did not increase the yield significantly.