Changes Of Soil Microflora And Activites Of Enzymes In Continous Cropping Strawberry In Solar Greenhouse

Changes of soil microflora and activities of enzymes in annual and continuous cropped years soil, and superiority fungi and bacteria were appraised, in solar greenhouse in honggu district of Lanzhou city were studied in the paper. Influences of different fertilizers as well as phenol accumulating status on soil microflora and activities of enzymes in strawberry in solar greenhouse were studied deeply by pot experiments, and the key results are as following:1 Contunuous cropping obstacle was presented in solar greenhouse in honggu district of Lanzhou city, output of strawberry was decended remarkablely .The number of soil fungi were decreased from annual crop to that of continuous crop. The number of soil bacteria and actinomyces were increased from the annual crop to that of continuous crop. The number of soil fungi increased with the growing of strawberry, and the number of soil bacteria and actinomyces increased in earlier stage and decreased later period, the peak value appeared in first fruit period.The result of fungi separate showed: Fusarium, Phytophthora and Rhizoctonia were main physiology group. The percentage of Fusarium were more than 30%, peak value were 62%. The number of Phytophthora achieved 18.33% in full fruit period in continuous crop, which was the maxium percentage. The peak percentage of Rhizoctonia was 21.46%.The changes of each kind of microorganism were all clearly both comparison in different crop years and different grow seasons. The number of aerobe cellulolytic,nirrifiers and oligotrophic azotobacter were decreased from annual crop to that of continuous crop, but oligotrophic,cellulolytic and aerobe azotobacter were increased. The changes of activities of soil enzymes were related with strawberry grow season: the activities of catalase,protease,invertase and urease were all increased in different grow seasons from annual crop to that of continuous crop. The activities of polyphenol oxidasea were higher in continuouse crop year soil in seedling period and full fruit period, lower in annual soil in first fruit perid and wane period.2 The number of soil microorganism were related with the concentrations of phenol treatment, the number of fungi,bacteria and actinomyces appeared trends of falling after rising. The different was : the peak amount of bacteria and actinomyces were under 80μg﹒g-1,while the fungi was under 120μg·g-1.The amount of nitrogen physiology groups appeared trends of falling after rising with the concentrations of phenol increased, the peak amount were under 80μg﹒g-1. With the grow of strawberry and the time of treatment lengthen, the amount of Fusarium and Rhizoctonia were all increased under each treatment concentrations, the rising trends slowed under 160μg﹒g-1treatment.The activities of catalase,protease,polyphenol oridasea,invertase and urease appeared trends of falling after rising, while their peak value appeared in different concentrations of phenol.3 Influences of different fertilizer on soil microflora and enzymes activities were significant, and the results indicated that there has a correlation between them and soil fertility.