Micro Ecological Research Of Different Panax Notoginseng Planting Soil

This study is based on soil that grow notoginseng in Yunnan.We collected fallow fieldsand soil that growing Panax notoginseng for1,3and5years in Yan mountain in Yunnanprovince.We compaired the difference of the numbers of microorganisms, physiologicalgroups of microorganisms, type of soil fungi，soil enzyme activity and nutrients in fallowfields and growing notoginseng soil in order to find the reasons that may cause continuouscropping obstacles. We collected healthy and green and dry root rot notoginseng in Shilin inYunnan. We compaired the amounts of microorganisms, physiological groups of microorgani-sms, soil enzyme activity and nutrients of soil around Panax notoginseng root in order tofind their relationship with green and dry root rot. We collected fallow soil, interval soil of1,3,6and9year.We compaired amount of microorganisms, physiological groups of microorga-nisms, soil enzyme activity in order to find the difference of soil, finding the influence ofcrop rotation to soil The study results are as follows:1. By studying the soil of different cultivated year, We concluded the following results：The cfu of bacteria, actinomycetes, nitrosobacteria, aromatic decomposition microbes,azotobacter and potassium bacteria in Panax notoginseng growing soil are smaller than that offallow soil, but the cfu of fungus showed no significant difference. The trichoderma was onlyisolated from the fallow soil and notoginseng growing soil for1year. Except fallow soil,fusarium was isolated from notoginseng growing soil. The activity of sucrose, diastasumdiastace, Catalase, polyphenol oxidase and phosphatase in Panax notoginseng growing soilare smaller than that of fallow soil, but the cellulose, urease and Peroxidase showed noregular pattern. The organic matter, available N, available Ni, available Cu, available Zn andavailable Fe in notoginseng growing soil are smaller than that of fallow soil, but the watersoluble Ca is higher than that of fallow soil, available N, available P, available Mn and watersoluble Mg showed no regular pattern. There are different changes in notoginseng growingsoil such as microorganisms, soil enzyme activity and nutrients, and that lead to continuouscropping obstacles.2.We compaired the amount of microorganisms, soil enzyme activity and nutrients of soilaround Panax notoginseng root in order to find their relationship with green and dry root rot. The result show: the cfu of bacteria in rhizosphere soil and root of diseased plant are largerthan that of healthy plant，but the cfu of actinomycetes and fungus are smaller. The numbersof physiological groups showed different changes with the change of environment inrhizosphere soil and root. The sucrase, cellulase, catalase and total phosphatase activities inno-rhizosphere soil of healthy plants are significantly higher than diseased plant, but theperoxidase and polyphenol oxidase activity is lower to diseased plant. The available N,available phosphorus, available potassium in root rot soil are higher than that of healthy plant,but the water soluble magnesium is lower than that of healthy plant. The results indicated thechange of microecology in rhizosphere soil and root of diseased plant, especially the increaseof bacteria is the most significant feature.3. By studying the soil of different interval year, the results are as follows：Except thefallow soil, the cfu of actinomycetes showed the raising trend with the growth of intervalyear.Except1interval year, the cfu of fungus showed no significant different. The cfu ofbacteria showed the lessen trend with the growth of interval year. The cfu of nitrosobacteria,aromatic decomposition microbes, potassium bacteria and phospho bacteria in interval soil areless than that of fallow soil, but the cfu of azotobacter and cellulose decomposition bacteriashowed no regular pattern. The activity of acid phosphatase are larger than neutralphosphatase, and neutral phosphatase are larger than alkaline phosphatase. The activity ofphosphatase in fallow soil are larger than that of interval years. The activity of catalaseshowed a lessen trend with the growth of crop rotation, but the activity of sucrose, celluloseand polyphenol oxidase showed no regular trend. After crop rotation, there are changes inmicroorganisms and soil enzyme activity.