溶磷菌对大豆根际土壤酶活性及微生物群落的影响

Effects of phosphate-solubilizing bacteria on the soil enzyme activities and microecology of soybean rhizosphere

为研究添加外源溶磷菌wj1和wj3对大豆根际土壤的影响及其改良盐碱土的可行性,以吉林省主推高产高油大豆品种"吉育406"为材料,将wj1和wj3菌液施入到不同处理的土壤中,分析外源溶磷菌对不同生育时期大豆根际土壤酶活性、土壤微生物数量和微生物群落的变化。结果表明:大豆生长的R2和R6两时期,混合菌能显著增加黑土中磷酸酶、脲酶、蔗糖酶和蛋白酶的活性;菌株wj1在整个生育期内提高了黑土磷酸酶活性;黑土添加溶磷菌对大豆根际各种微生物数量均有提高;菌株wj1有利于促进黑土中溶磷菌和自身固氮菌数量的增加,添加wj3和混合菌对整个生育期内土壤中氨化细菌和硝化细菌的数量增加效果明显;添加溶磷菌可显著增加混合盐碱土壤中微生物数量,改善土壤磷酸酶、脲酶和蔗糖酶活性;加菌处理的土壤微生物群落多样性与未接菌处理差异明显;V3-R6,黑土与混合土壤加菌处理均提高了土壤Shannon指数与微生物群落丰富度,增强了混合盐碱土中微生物代谢能力。添加外源溶磷菌可有效增加黑土及混合盐碱土土壤微生物数量,使土壤营养水平趋于合理。

To study the effects of phosphate-solubilizing bacteria （PSB） wjl and wj3 on the improvement of soybean rhizosphere soil or mixed saline alkali soil. Experiments were conducted by applying bacteria wjl and wj3 to different soil treatments and the main high yield and high oil soybean variety ＂Ji Yu 406＂ in Jilin Province was used as material. The effects of soil enzyme activity, soil microbial quantity and soil micro ecology of exogenous PSB on soybean rhizosphere soil were investigated. The results showed that= The activities of phosphatase, urease, invertase and protease by adding mixed bacteria into black soil were significantly increased at the R2 and R6 stages of soybean. Strain wjl could affect the phosphatase activity of black soil. The effect of the amount of microorganism was significantly affected by the additional PSB into the black soil at the early growth stage of soybean. Strain wjl promoted the increase of the quantity of PSB and nitrogen fixing bacteria of black soil. Strain wj3 and mixed bacteria displayed great impacts on the number of ammonifying bacteria and nitrifying bacteria during whole growth period. Adding PSB significantly improved soil phosphatase, urease and invertase activities, and the number of microorganisms of mixed saline alkali soil. The change of microbial community diversity was obvious between bacteria treatment and the control. The Shannon index and microbial community richness of black soil and mixed soil were increased by adding the PSB,and the ability of microbial metabolism in mixed saline alkali soil was enhanced from V3 to R6. In conclusion,adding PSB to black soil and the mixed saline alkali soil could improve the microbial quantity and result in reasonable soil nutrition level.