Study On Allelopathy Of Root Exudates Of Soilless Cultivation Of Ginseng

The allelopathy of root exudates of ginseng was considered to be the important reason ofcropping obstacle.The chemincal compositions of soil extracts and root exudates were differentbeceuse of the existence of rhizosphere microzone and the use of artificial chemicals.So theroot exudates of ginseng were collected by using soilless culture to study the realallelopathy.The main results were as follow:1. The collection of root exudates soilless cultivation of ginseng.The petroleum ether,chloroform, ethyl acetate, methyl alcohol and water were used to extract the soilless culturematrices and nutrient solution. The results of yield were1%,6%,4%,18%and71%respectively.The extraction ratio of nutrient solution by using methyl alcohol was2.54mg/L.2. The condition of the callus inducting of ginseng root and proliferation. The best explantwas ginseng stem in ginseng callus induction. The inductivity of hormone combinations wassignificantly higher than that of hormone alone.The best ratio of hormone combination was2,4-D(1mg/L)+NAA(1mg/L) and the best proliferative condition of callus was2,4-D(1mg/L)+NAA(3mg/L)+6-BA(2mg/L).3．The autointoxication of root exudates.①The three exudates had on inhibiting actionon ginseng root callus.The allelopathic inhibition of soilless culturing matrices, was highestand that of rhizospheric soils was lowest.②Ginseng root exudates had inhibitory effects onactivity of stress resistant enzyme.There was an positive correlation between concentration ofextract and days of culture, soilless culturing matrices was stronger.4．The chemical components analysis of root exudates of ginseng. The CG-MS analysisshowed that the components were mainly hydrocarbons, ketones, esters, phenols, phenolic acids,alcohols and acid etc. There were more than20kinds of chemical components in common,which was mainly acids and carbohydrates.There more than70kinds of chemical componentswere unique in each.