化肥有机替代对连作花生产量和根瘤固氮的影响.

This study investigated the effect of substituting chemical fertilizer with vermicompost and bio-organic fertilizer under equal amounts of N, P2O5, and K2O levels on peanut yield, nitrogen absorption, and fixation under continuous cropping. A two-year experiment was conducted in the long-term continuous cropping field of peanuts, including four treatments, such as vermicompost substituting chemical fertilizer(VM), bio-organic fertilizer substituting chemical fertilizer(BF), NPK chemical fertilizer(CF), and no fertilizer treatment as control(CK). The effect of organic fertilizer substituting chemical fertilizer on peanut yield and nitrogen uptake and utilization were studied. The results showed that VM treatment significantly increased peanut plants′ harvest index and dry matter accumulation. The peanut yield of VM and BF treatments increased by 63.18% and 33.51% compared with CK. CF significantly reduced nodules′ number and fresh mass by 18.78%-50.82% and 24.29%-34.74%, respectively. Compared with CF, BF and VM increased the number of nodules by 53.20% and 69.56%, and fresh mass of nodules by 63.90% and 66.31%, respectively. The nitrogenase activity of BF and VM was 1.16 and 1.20 times that of CK and 1.15 and 1.19 times that of CF, respectively. The nitrogen content and nitrogen accumulation of peanut grain, leaf, stem, and root under fertilization treatment were higher than CK, among which VM treatment was the highest, followed by BF treatment. The nitrogen allocation ratio of peanuts was higher in grain than in leaf, stem, and root. VM increased the nitrogenase fixation potential of peanut nodules and the nitrogen allocation ratio to the grain but decreased the nitrogen allocation ratio to the root, while CF showed the opposite effect. The agronmic efficiency of nitrogen fertilizer of VM was 1.85 and 5.08 times that of BF and CF, respectively. partial factor productivity from applied nitrogen of VM(5.02 kg·kg-1 )and BF(4.11 kg·kg-1 )was significantly higher than that of CF(3.43 kg·kg-1 )and CK(3.08 kg·kg-1 ). Compared with CF and BF, VM showed stronger nitrogen uptake and utilization capacity. In summary, vermicompost substituting chemical fertilizer treatments enhanced the ability to convert peanut photosynthetic products into economic products, showing a stronger yield advantage. NPK chemical fertilizer showed a pronounced “Nmin inhibitory effect” while organic fertilizer (especially vermicompost) substituting chemical fertilizer treatments could alleviate the “Nmin inhibitory effect” which was mainly attributed to the fact that vermicompost substituting chemical fertilizer treatments could maintain the nitrogen fixation potential of nodules by increasing the nitrogenase activity of nodule, and changed the nitrogen allocation of peanut plants, and finally enhanced the nitrogen uptake and utilization capacity of peanut plants. [ABSTRACT FROM AUTHOR]