Study On The Characteristics In Rhizosphere Soil Of Ginseng Red Skin Disease

Ginseng red skin disease was a very common and increasingly serious disease in ginseng cultivation. The incidence of Ginseng red skin disease may be up to 80% in some areas. Ginseng red skin disease may result in downgrading of goods and causing huge economic losses. The change of rhizosphere soil properties, especially microbial flora composition changes will direct impact on the healthy growth of plant roots and is particularly evident in crop rhizosphere. The object of this study was characterization and comparison of the physico-chemical properties, enzymatic activities and microbial diversity of soil collected from Changbai Mountains to identify any possible relationship between rusty root of ginseng and soil characteristics. Aiming to explore the mechanism of microbial pathogenesis rusty root disease. Providing a reference for ginseng soil improvement and effective prevention of the occurrence of rusty root disease. Aim to promote the healthy development of the ginseng industry. The main results are as follows:1. Detected and analyzed the ginseng rhizosphere soil physical and chemical properties by using conventional agricultural chemical analysis method. The results showed: ginseng rhizosphere soil water content was significantly higher in rusty root than healthy root group in five sample spots(p<0.05).The rhizosphere soil water content was higher 23.55% in rusty root than the healthy group. Soil bulk density was higher in rusty root than healthy root group in all samples. And it was higher 10.23% in rusty root than the healthy. The ginseng rhizosphere soil pH was lower in rusty root than healthy root group in all sample spots. The ginseng rhizosphere soil pH was lower 5.56% in rusty root than healthy root group. Available N and P of rusty root ginseng rhizosphere soil was generally lower than healthy root group. The ginseng rhizosphere soil available K was significantly lower in rusty root than healthy group in five sample points(p<0.05). Organic matter of ginseng rhizosphere soil was significantly higher in rusty root than healthy root groups in B and E sample spots. The ginseng rhizosphere soil organic matter was on significant between rusty root and healthy root group in A, C and D sample spots. The organic matter of rusty root ginseng rhizosphere soil was 14.32% higher than the healthy group. The Fe content of ginseng rhizosphere soil was significantly higher in rusty root than healthy root group in all sample spots(p<0.05). The Mn content of ginseng rhizosphere soil was higher in rusty root than healthy root group in five sample spots. The Mn content of ginseng rhizosphere soil in rusty root group was 18.65% higher than the healthy group. The Al, Cu, Zn and Ni content of ginseng rhizosphere soil was on significant between rusty root and healthy root groups in all sample spots.2. Detected and analyzed the ginseng rhizosphere soil enzyme by the reducing of substrate and the generation of product. The results showed: the ginseng rhizosphere soil polyphenol oxidase activity was significantly higher in rusty root than healthy root groups in five sample spots(p<0.05). The urease activity of ginseng rhizosphere soil was higher 38.33%-79.45% in rusty root than healthy root groups. The overall level of catalase activity of ginseng rhizosphere soil was higher 4.24% in rusty root than healthy groups. The ginseng rhizosphere soil acid phosphatase activity was lower in rusty root than healthy root groups in five sample spots.3. Using high-throughput sequencing technique for ginseng rhizosphere soil bacterial 16 S rDNA genebased molecular analysis of V3 and V4 regions. The results showed: the bacterial abundance indices(Chao1 and ACE) were no significant difference between rusty root and healthy root groups in five sample spots. The bacterial diversity index(Shannon and Simpson) were showed that rusty root was higher than healthy groups in the five sample spots. The Proteobacteria, Actinobacteria, Acidobacteria and Verrucomicrobia were the common dominant microorganisms in ginseng rhizosphere soil accounted for 57.20%-73.34%. The proportion of Proteobacteria, Acidobacteria, Gemmatimonadetes and Nitrospirae were higher in rusty root than healthy root groups in all sample spots. The proportion of Actinobacteria, Verrucomicrobia, Planctomycetes and WPS-2 were lower in rusty root than healthy root groups in all sample spots. The proportion of bacterial genus such as Rhodanobacter, Burkholderia, Gemmata and Oryzihumus were higher in rusty root than healthy groups in all sample spots. However, Rhodoplanes、Nitrospira、Pseudomonas、Thiobacillus、Hyphomicrobium and Pedomicrobium were lower in rusty root than healthy groups. There were significant differences in soil microbial community structure in ginseng rhizosphere soil between rusty root and healthy groups, and the soil organic matter, pH and Mn were three key environmental factors affecting ginseng rhizosphere soil bacterial community structure. Where soil pH and organic matter were the key environmental impact factors of ginseng rhizosphere soil bacteria of the main genus.