Study On The Relationship Of Soil Characteristics And Red Coating Root Disease Of Ginseng Under Forest

The soil characteristic may be affected by the root exudates, litters came from different species of trees, and the soil characteristic may affect the quality and quantity of Ginseng Under Forest. In this paper, we took Ulmus pumila L、Larix gmelinii. Kuzen、Populus L、Juglans Mandshurica Maxim as the study object, detected and analyzed the soil nutrient, soil enzyme, soil inorganic elements and soil microbial community structure, combined the SHBI of Ginseng red coating root disease, wished to define the difference. Main content were as follows:1. Detected and analyzed the soil nutrient by conventional soil agricultural chemical analysis. The results showed:The expression of soil nutrients under different trees were not the same. The C.V of available phosphorus and available potassium were higher than that of organic and available nitrogen, they were0.50and0.48. The available phosphorus, available potassium were supreme under Populus L,; the organic, available nitrogen were supreme under Ulmus pumila L, they were10.47%and255.42mg/kg; There were negative correlation between the SHBI of Ginseng red coating root disease and the available nitrogen, phosphorus, potassium; The SHBI of Ginseng red coating root disease were supreme under Ulmus pumila L and Juglans Mandshurica Maxim.2. Detected and analyzed the content of Al, Cd, Cr, Cu, Fe, Mn, Pb in the soil of Ginseng under forest. The results showed:There were great differences of soil inorganic elements under different trees; The C.V of total Cu was supreme among different trees, it was0.33, the C.V of available Fe was supreme among different trees, it was0.57; The content of total Cd exceed the second level criterion of Standard of Soil Environment (GB15618-1995), it was0.390mg/kg; The available content of Cd, Cu, Fe, Pb, V, Zn were both higher under Juglans soils than any other trees, the available content of Al, Cr were both higher under Pine soils than any other trees, the available content of Cd, Cu, Fe were both lower under Poplar soils than any other trees. The enrichment factors of Zn, Cu, Cr in Ginseng under forest were supreme, they were0.445,0.47and0.279, and the enrichment factor of V were lowest among different inorganic elements; The SHBI of Ginseng under forest were supreme under Juglans and lowest under Poplars. There was a significant positive correlation between the SHBI of Ginseng under forest and the available Fe, the correlation index was0.796, and there was a significant negative correlation between the SHBI of Ginseng under forest and the available Mn, the correlation index was0.76.3. Detected and analyzed the soil enzyme by the reduce of substrate and the generation of product. The results showed:The urease activity were supreme under Populus L; the peroxidase activity and phosphatase activity were supreme under Ulmus pumila L; the Invertase activity were supreme under Juglans Mandshurica Maxim; the activity of enzyme were lower under Populus L. There were positive correlation between the SHBI of Ginseng red coating root disease and the peroxidase activity, phosphatase activity.4. Detected and analyzed the content and composition of the soil microbial community structure in the soil of Ginseng under forest under different trees. The results showed:The total PLFAs, bacterial PLFAs and fungal PLFAs of soils were quite different under different trees; The values of bacterial PLFAs/fungal PLFAs were among3.55-10.95and were significant different, the values of G+PLFAs/G PLFAs were between2.43-3.14; The total PLFAs had a positive correlation with the available N, Peroxidase and Phosphatase, the fungal PLFAs had a positivet correlation with organic matter, available N and Phosphatase, the G+PLFAs had a negative correlation with organic matter, available N and Phosphatase, the G PLFAs had a positive correlation with available N, Peroxidase and Phosphatase; The relationship of the SHBI of Ginseng red coating root disease and14:0,18:0,10Mel8:0were closely.