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In recent years, the value of ginseng more and more recognition and attention of the world, the growing scale of the ginseng industry more widely. However, ginseng continuous cropping obstacles, has been plagued academia. Reuse of old ginseng production of ginseng industry has not been able to fundamentally solve a major problem. Ginseng and other perennial plants, bogey strong, can not be cropping can not cropping. Large number of tests to prove: Ginseng continuous cropping, crop rotation would be a serious disease, burn be serious rot. New forest soil farmland planted ginseng, are faced with the old ginseng Ginseng Industry sustainable development. Ginseng soil improvement and sustainable planted parameter is an urgent need to solve the chronic problem of ginseng, American ginseng cultivation industry, is fifty years many ginseng industry producers and researchers research directions. Start from the point of view of the root exudates, ginseng soil test materials were studied Continuous Cropping on soil micro-environment parameter soil; repair of different plants on the old ginseng soil micro environment; Ginseng different growth stages of soil enzyme activity changes. The results show that: 1 in Continuous Cropping ginseng soil microbial quantities larger. Compared with the forest soil under soil bacteria and actinomycetes with increasing years of continuous cropping and reduce bacteria were reduced from 62.9% to 49.1%, the actinomycetes was reduced from 35.2% to 22%, reduce the number of actinomycetes more significantly, the number of fungi increased with increasing years of continuous cropping, rose to 27.9% from 1.9%. , The rhizosphere B / F values ??show a downward trend with increasing years of continuous cropping, soil fertility on a downward trend, ginseng continuous cropping soil by a type of bacteria to fungi development. 2 in Continuous Cropping ginseng soil microbial populations has also undergone changes. In the forest soil under the soil bacterium Pseudomonas fluorescens, Enterobacter cloacae and cheese Brevibacterium main groups, compared with forest soil under the plant ginseng ginseng soil, the type of bacteria did not change significantly; ginseng soil planted ginseng in 2002 and four years the Pseudomonas fluorescens disappear, Micrococcus luteus and holly Arthrobacter planted ginseng ginseng soil in 2002 and four years. In the forest soil under soil fungi Penicillium, Aspergillus and Trichoderma, with increasing years of continuous cropping, soil rhizosphere almost no Trichoderma species significantly reduced; cropping 2 years and 4 years cropping parameters land rhizosphere soil sticky beam spp and Fusarium. Compared with forest soil under, with increasing years of continuous cropping, soil actinomycetes population did not change significantly, are based on the genus Streptomyces based. Compared with forest soil under ginseng soil enzyme activity by a different degree of reduction. However, with increasing years of continuous cropping, different enzymes have different trends. With the increase of years of continuous cropping, polyphenol oxidase from 0.4963 mg/1g · 2h dropped to 0.2060 mg/1g · 2h, the protease from 0.6970mg / g 24h down to 0.5469 mg / g · 24h invertase from 1.2887 ml / g 24h down to 0.7543ml / g · 24h, this trend pH trends. Catalase, urease and acid phosphatase activity of the three enzymes show a downward trend after two years of continuous cropping, the catalase from 0.1802ml / g 20min reduced to 0.1050 ml / g · 20min, urease from 23.1743 mg / g · 24H down to 4.2331 mg / g · 24h, acid phosphatase from 6.5411 mg / g · 24h down to 2.1484 mg / g · 24h; Cropping enzyme activity after 4 years there upward trend over catalase reached 0.1632 ml / g · 20min, urease to 8.7748 mg / g · 24h, acid phosphatase up to 2.3087 mg / g · 24h. 4.3 species have different repair the number of microorganisms in the soil of old ginseng. Get picked up the proportion of bacteria and actinomycetes, fungi ratio corresponding decrease in, old ginseng soil restoration descending order followed by alfalfa, white clover, Suzi. Alfalfa, the Suzi and white clover Three phytoremediation, the dominant species in the soil of the change. Compared with the planted ginseng four-year old ginseng soil, after the the Bioremediation reference to soil, Pseudomonas fluorescens appeared and the dominant position, Micrococcus luteus disappear; Suzi and white clover repair ginseng soil, cheese Brevibacterium disappear. Fungi and actinomyces did not change significantly. After phytoremediation, soil enzyme activities showed different degrees. Activity compared with the control soil, planting alfalfa in order descending order to the soil in the degree of activity of the repair sucrase, an increase of 78.79%, urease, 67.92%, polyphenol oxidase descending, increased by 44.71%, acid phosphatase, improve the 6.95% protease, 3.07%, catalase, an increase of 2.76%; planting Perilla after 1 year, 6 elevated enzyme activity order sucrase, an increase of 76.83%, protease, improved 11.14%, acid phosphatase, a 6.94% increase in polyphenol oxidase, an increase of 2.96%, urease, a 2.77% increase in catalase, 2.76%; 1 year after planting white clover, activity increased descending order followed by invertase, an increase of 76.03%, polyphenol oxidase, 29.17%, acid phosphatase, improve 6.93% protease, a 5.3% increase in catalase 2.33%, urease, a 1.28% increase. 7.6 enzyme activity in different periods have different trends. Compared with the control of enzyme activity in the soil, ginseng leaf polyphenol oxidase activity occurred significantly reduced, along with the growth of ginseng After flowering, fruit period activity gradually increased, reached 0.3602mg/2h · 1g , development and development of red berries of activity have come down, reach 0.3282mg/2h 1g, and finally to the harvest activity has been greatly increased, reaching the highest value of 0.4085 mg/2h · 1g. Ginseng after transplanting, soil catalase activity with growth gradually reduced, there is an upward trend in growth to the fruit of activity, 0.1640ml / g · 20 min to the red berries of enzyme activity but also a downward trend, this when activity reached the lowest value of the entire development period, for 0.1172ml / g · 20min maturity of hydrogen peroxide activity have risen. With the growth of ginseng, sucrase activity gradually decreased, and grown to a fruit phase, enzyme activity of the entire growth period the minimum value of 1.2584 ml / g · 24h development to hongguo period, enzyme activity reached the maximum value of the entire growth period, for 1.3024ml / g · 24h, harvest invertase activity decreased slightly. With the growth of ginseng, sucrase activity gradually decreased, and grown to a fruit phase, enzyme activity of the entire growth period the minimum value of 1.2584 ml / g · 24h development to hongguo period, enzyme activity reached the maximum value of the entire growth period, for 1.3024ml / g · 24h, harvest invertase activity decreased slightly. Throughout the development process, ginseng activity of acid phosphatase activity in different growth stages of change. Acid phosphatase activity trend similar to the trend of the invertase activity. Leaf expansion to the fruit of the enzyme activity decreased to the fruit of as low as 0.3161 mg / g · 24h, from the fruit of the red berries of a rising trend, enzyme activity, the harvest period, activity decreased slightly . Ginseng after transplanting the previous stage, that is, from the leaf of the fruit of the soil urease activity gradually increased with the growth of ginseng, fruit of the enzyme activity reached the highest value, 22.4644 mg/g.24h. Urease activity on a downward trend continue to grow ginseng, ginseng in the red berries of the decrease in enzyme activity, urease activity of the harvest increased slightly. With the continuous growth of ginseng, soil protease activity in the performance of a downward trend in the first increases and then, when the ginseng growing fruit, the highest peak enzyme activity, enzyme activity .5919 mg / g · 24h to the growth of the late activity was downward trend.
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