Study On Ginseng Allelopathy And The Elements Of Unable Successive Cultivation

Panax ginseng C. A. Mey is one of a China noble herb of medicine. The cultivating so il shorten is one of the main problem of obstacle the development of the industry of gins eng. In the long term had we had to cut forest to cultivate ginseng. If we want re-cultiva te on the soil of ginseng harvested, it needs thirty years because of the unable successiv ely cultivation. In china there is limited forest area for ginseng cultivating, and the soil re generation needs a long period. The resource of ginseng cultivating soil having been close d toexhaust. Some countries of main ginseng product such as China, Corea, Japan, Americ a and Canada all have researched the problem of ginseng unable successive cultivation, th ey carried out lots of viewpoints, mass of researchers believed that the degradation soil ofphysical and chemical qualities and the pathogeny microorganism are the main reason of ginseng unable succession cultivating, but it can only mitigate the symptom of unable s uccession cultivation on a certain extent by meliorated soil, soil bacterium and wireworm killing, there still exist the phenomenon of heavier disease and lower output. So the upper viewpoint are not be accepted in common. So we studied ginseng allelopathy on its unab le succession cultivating, the main results as follows:1 Setting up the testing technique of the activity of ginseng allelochemical by the metho ds of burgeoning and callus, definituded that the self toxin comes from the soil of rhizosp here and the plant of itself. The soil extract of 50g/l can inhibit the burgeoning ratio of g inseng seeds up to 90%, 100g/l up to 100%.2 Utilizing HPLC-MS identified the structure of ginseng allelochemical. The substances identified by GC-MS as follows: Hexadecenoic acid, methyl ester; Pentadecanoic acid, 14-oxo-, methyl ester; 9,12-Octadecadienoic acid (Z,Z)-; Dibutyl phthalate, Eicosanoic acid; Bicyclo[10.8.0]eicosane, (Z)-; Tricosane; 5,6-Tetramethylenetetrahydro-1, 3-oxazine-2-thione-4-spirocyclohexane; Hexanedioic acid, bis(2-ethylhexyl) ester; Pentacosane; 1, 2-Benzenedic arboxylicacid, diisooctylester; Cyclohexadecane, 1, 2-diethylBenzeneacetaldehyde, 4-dimethoxy-.al pha.-(2-propenyloxy)-,oxime4,6,7-Trimethoxy-9-[3,4-(methylenedioxy)phenyl]naphtho[2,3-C] fur an-1(3H)-one; Friedooleanan-3-one; Stigmast-7-en-3-ol, (3.beta.,5.alpha., 24S)-; 3, 7, 11-Trimethyl-dodeca-2, 4, 6, 10-tetraenal; Stigmast-4-en-3-one; Friedelin; Pentadecanoic acid, 14-methyl-, me thyl ester; Dibutyl phthalate; Hexadecanoic acid, 14-methyl-, methyl ester, Methyl 7-methylhe xadecanoate; 9-Octadecenoic acid (Z)-, methyl ester, 15-Octadecenoic acid, methyl ester; Octad ecanoic acid, 10-methyl-, methyl ester; Cyclopropaneoctanoic acid, 2-octyl-, methyl ester; Dib utyl phthalate; 9, 17-Octadecadienal, (Z)-; Octadecanoic acid, methyl ester; Chloromethyl 8-chlo rododecanoate; Diisooctyl adipate; Cyclohexane, 1-(cyclohexylmethyl)-2-ethyl-, cis-, 13-Docose noic acid, methyl ester, (Z)-; 2, 6, 10, 14, 18-Pentamethyl-2, 6, 10, 14, 18-eicosapentaene; 4-(3, 4-Dim ethoxybenzylidene)-1-(4-nitrophenyl)-3-phenyl-2-pyrazolin-5-one; delta.-Selinene; Cyclononasilox ane, octadecamethyl; Cholest-5-en-3-one, 4, 4-dimethyl-; Morphinan, 8-didehydro-4, 5-epoxy-17-me thyl-3, 6-bis[(trimethylsilyl)oxy]-, (5.alpha.,6.alpha.)-;Benzophenone-2,4',5-tricarboxylic acid,tri methylester; Eicosane; Tetracosane; Heneicosane; Hexacosane; Heptacosane; Docosane; 9-Hexacos ene; Nonacosane; Eicosane, 10-heptyl-10-octyl-; 3-Eicosene,(E)-; Triacontane; Dotriacontane; Didode cylphthalate; 2-Butenenitrile, 4-phenyl-2-(1-methoxypyrrolidin-2-on-5-yl)-; Diisooctyl adipate; E-6-Octadecen-1-ol acetate; Octadecenoic acid.Six compounds extracted by HPLC-MS, three of these compounds have the special react ion of phenolic acid, one of these the main molecular weight are 302, 330, 346.3 Disscussed the activate of root system, plant hormone and the structure of cell functio n at ginseng succession cultivate, the result is, ginseng allelopchemical can change the org anize of root point, disposed by allelochenical, the starch grain in the cell of root point di vision district can represent a certain extent of phenomenon of hollow, and disappeared i n gradually. That is to say, the root cells are losing normal function, so they should unable to finish normal life activate, the inner growth hormone is reducing, the activity of root system is reducing simultaneously.4 Enable to make ginseng successive cultivation, some efforts were made by microbiotic, Nutration, physiology, growth and development of ginseng. A soil amendment was made up according to the upper results. Treated with the amendment, the soil grown ginseng as reclamated through increasing the contents of N. P and K, which maybe caused by the function of decomposing phosphate and potassium by microbiotic activity to increase some inorganic acids and organic acids. The activity of oxidative enzyme in the soil grown gins eng was increased after the soil treated with the amendment, and the more amendment wa s used, the higher activity should be observed. After disposed with the amendment, the in net ABA contents in the stem of ginseng grown in the treated soil. Shown a similar chan ge during grown season, but were lower at the harvest period them that of grown on the untreated soil. While the content of IAA in the stem of ginseng grown on the treated soil was higher during the growth period and lower at harvest time compared with that of grown on the untreated soil.