[Isolation and identification of rhizobacteria RS-3 from Panax ginseng and evaluation of its antagonistic activity].

A rhizobacteria strain named RS-3 exhibited inhibitory activity against all five Panax ginseng pathogens was isolated from the root of P. ginseng. This strain was identified as Bacillus amyloliquefaciens based on its morphological character and 16S rDNA sequence. Antagonistic activity experiments indicated that the strain could strongly suppress Botrytis cinerea Pers with an inhibitory rate of 54.4%, suggesting the potentialities of biocontrol agent against diseases that frequently happen on ginseng.

[Advance in studying early bolting of Umbelliferae medicinal plant].

The early bolting has become one of the key issues affecting the Umbelliferae herbs production. The early bolting does not only reduce herbs production but also affect the active ingredients of plants. The concept of early bolting, physiological theory, induce factors of the quality of medicine and, control technology about the early bolting of Umbelliferae are integrative reviewed in the paper. Its occurrence mechanism include: genetic factors, environmental and ecological factors, endogenous hormones, sowing, fertilizer and other production management measures. For the above occurring mechanism, the proposed prevention measures are as follows: preferably germplasm, sowing, rational fertilization, exogenous hormones, shading, reed head cut off, cut fall the leaves, reasonable planting density and other agronomic measures can reduce its bolting rate. And the early bolting problem focused for future research are mentioned, including: development of authentic ingredients cultivation technical specifications, screened early bolting hormone inhibitor, in-depth study of the mechanism of early bolting, reveal its early bolting gene and key ecological factors. The research of vernalization gene, gene regulation of flowering early bolting will solve the problem of quality and production reducing fundamentally caused by the early bolting.

[Effects of Lime on Seedling Growth,Yield and Volatile Constituents of Atractylodes lancea].

OBJECTIVE: To investigate the effects of different amounts of lime on yield and quality of Atractylodes lancea, and to provide reference for the herb growing site soil improvement and self-poisoning ease. METHODS: Add different gradients of lime, and then measure their growth targets, yield and four kinds of volatile constituents content(hinesol, atractylone, ß-eudesmol and atractylodin). Volatile constituents yield per plant was calculated. RESULTS: Adding 160 g/m2 lime had a significant role in promoting the growth and yield of herb; Adding 80 g/m2 lime was conducive to the volatile constituents production, and adding lime decreased the atractylone and atractylodin content, while increased the hinesol and ß-eudesmol content; Adding 160 g/m2 lime promoted the volatile constituents yield per plant. CONCLUSION: Adding lime plays a role of neutralize soil pH, antibacteria and prevention incognita, and has a certain degree of ease autotoxicity and obstacle,and then promotes the yield and volatile constituents production of Atractylodes lancea.

[Mitigative effect of micribial degradation on autotoxicity of Panax ginseng].

Continuously cropping obstacle restricts ginseng production and rational use of land resource severely, and autotoxicity is one of the most important factors. In our previous work, ginseng autotoxin degrading bacteria were isolated, in the present re- search, plate culturing method and traditional physiological and biochemical method were used to analyze biological indices and protective enzyme activities, in order to elucidate the mitigative effect of autotoxin degrading bacteria on autotoxicity of P. ginseng. Results indicated that, except for palmitic acid, autotoxicity of benzonic acid, diisobutyl phthalate, diisobutyl succinate, and 2,2-bis (4- hydroxyphenyl) propane on the growth of ginseng seeds was significantly alleviated after autotoxins degrading bacteria was inoculated, and which have no evident difference with control. Except for benzoic acid, enzyme activity of SOD, POD and CAT in other autotoxin degrading treatments decreased significantly. The present research showed that, microbial degradation could alleviate the autotoxicity of autotoxins on ginseng seeds effectively, and which will be helpful for the resolution of ginseng continuously cropping obstacle problem.

[Isolation and characteristics of Panax ginseng autotoxin-degrading bacterial strains].

In this study, traditional plate culturing method was used to isolate autotoxin-degrading microbial strains, and which were then identified by 16S rDNA homological analysis and morphological characteristics. Furthermore, the growth and autotoxin-degrading efficiency of them were analyzed by liquid culturing method and GC-MS to illustrate their autotoxin-degradation characteristics. As a result, five bacterial strains having autotoxin-degrading activity were isolated from 6-years ginseng nonrhizospheric soil successfully, and which can growth successfully by taking autotoxins added artificially as carbon source in liquid culturing condition. Results indicated that it was feasible to isolate autotoxin-degrading bacteria from ginseng nonrhizospheric soil, and the isolated bacterial strains can be used to degrade autotoxins in soils once planted Panax ginseng.