| This study aims to investigate the effect of potato continuous cropping on soil properties, thus clarifying factors contributing to continuous cropping obstacles, using pot culture experiments. We analyzed soil properties including microbiological compositions, fertility, physicochemical properties and contents of phenolic acid and allelochemicals of potato continuous cropping soil, and performance of potato seedlings. The results indicated that soil salinity, alkaline hydrolysis nitrogen content and soil bulk density increased, as the continuous cropping prolonged.Activities of urease, catalase, alkaline phosphatase and invertase decreased markedly when continuous cropping lasted for 5 and 7 years, while the quantity of soil’s bacteria and actinomycetes decreased. The content of chlorophyll, activities of antioxidase, root activity and net photosynthetic rate decreased significantly when the continuous cropping lasted for 5 and 7 years. As a whole, continuous cropping obstacle was not obvious when continuous cropping lasted for 3 years. But potato continuously cropping lasted for 5 and 7 years, a series of biotic and abiotic stresses were triggered due to increasing of compositions of soil fungi, and the activity of key enzyme, the changes of physicochemical properties, and phenolic acid and allelochemicals contents, resulting in continuous cropping obstacle. |