连作对马铃薯土壤微生物区系和产量的影响

EFFECTS OF CONTINUOUS CROPPING ON SOIL MICROFLORA AND YIELD OF POTATO

以马铃薯连作1、3和5年的土壤为研究对象,分析了土壤微生物区系和产量的变化。结果表明,随连作年限的增加,土壤中细菌和放线菌数量呈下降趋势,真菌呈上升趋势,轮作与连作1、3和5年间的土壤细菌、真菌和放线菌差异均达极显著水平。与轮作相比,连作1年、3年和5年的土壤纤维素分解菌数量分别下降了21.4%、42.9%和50.0%,固氮菌分别下降了13.0%、39.1%和60.9%,氨化细菌分别下降了2.6%、17.1%和17.1%。随着连作年限的增加,马铃薯产量下降幅度逐年增加,但差异均不显著。

Soils with continuous cropping potato for 1, 3 and 5 years were used as test materials to study variations of microflora in rhizophere and potato yields. Results showed that to study the numbers of bacteria and actinomycetes decreased with the increase of continuous cropping years, while the numbers of fungi was in an increasing trend, and were doserved in the changes in bacteria, fungi and actinomycetes between crop rotation and continuous cropping for 1, 3 and 5 significant difference years. The number of Cellulose-decomposing bacteria for 1, 3 and 5 years decreased by 21.4% ,42.9% and 50.0,% respectively, with the number of ammonifying bacteria decreased by 13.0% ,39.1% and 60.9% , and the number of azotobacter decreased by 2.6% , 17.1% and 27.6% , compared to those in soil with the crop rotation soil. The increase of continuous cropping years, the yields of potato decreased slightly with the increase of continuous cropping years.