The Quantitative Study on the Dynamic Trend of Fusarium Population Abundance in Soybean Field under Different Fertilization Management

At the five growing stages,the abundance of Fusarium population in black soil under three fertilization managements was quantified using the Plating Counting method and Real-time QPCR method.Fertilization management included no fertilizer (NF),nitrogen and phosphorous chemical fertilizer (NP) and chemical fertilizer with manure (NPM).The result of Plating Counting method showed that the maximum of Fusarium CFU in NF and NP treatment was 1.5×10³ and 3.1×10³ g^-1 dry soil at R1 stage.The peak value in NPM treatment was 1.9×10³ at V3 stage.However,the dynamic trend of Fusarium CFU in each treatment during the growth stages or the difference of CFU values at the same stage was not significant,indicating the quantified detection of Fusarium abundance was infeasible using the Plating Counting method.The result of Real-time QPCR method indicated that the peak values of Fusarium DNA amount in the three treatments occurred at the same stage.The values of DNA quantities in the three treatments were 99.6,77.1 and 140.8 pg per gram dry soil,respectively.Meanwhile,the dynamic trend of Fusarium abundance in three fertilization treatments was similar.The amount was increased from V3 stage and then decreased after their peak values.It indicated that this method was sensitive to investigate the abundance of soil Fusarium population; and the fertilizer not only could affect the amount of Fusarium DNA,but also Time new romeen.