Primary Isolation And Identification Of The Antifungal Composition Of The Extration From Xanthium Sibiricum

(Pratacultural Institute,Gansu Agricultural University,Lanzhou,730070)The fungistatis of the extracts of Xanthium sibiricum were tested with Botrytis cinerea Pers.,Rhizoctonia solani,Fusarium oxysporium Schl.,Cladosporium cucumerinum Ell. et Arthur ,Alternaric solani(Ellis et Martin)Jones et Grout and Blumeria graminis f. sp tritici .The results were as follows:1. By testing the in vitro(growth rate and spore germination method) and vivo (cucumber cotyledon method )activity of the extracts of different part of Xanthium sibiricum ,which was collected from different areas,against the tested fungi, we found that the extraction of the stem and leaf of it from Lanzhou had higher antifungal activity.2.The house toxicity of the extraction of the stem and leaf of Xanthium sibiricum in Lanzhou was tested,the inhibition rate of XSAE to the hyphae growth of the 5 tested fungi was higher than that of XSAE0. The fungistatis of ASXE against Botrytis cinerea,Rhizoctonia solani and Fusarium oxysporium was higher than the other two tested fungi,and when the concertration was 0.05g/mL,the inhibition reached to 100% to the three tested fungi.While XSAE0 had high activity to Botrytis cinerea,the LD-P was y = 0.1694x - 7.1875,the EC50 was 337.59ug/mL.XSAE had better controlling effect on the Blumeria graminis f. sp tritici,and when the concertration was 0.15 g/mL,it`s protection and curling effect were both slightly lower than the standard fungicide Triadimefon.XSAE had higher stablity on the condition of different tempretureand heat preservation time,but on that of alkaline it lost the activity easily ,while the activity didn`t reduce too much. 3. The antifungal composition of AXSE was isolated primarily with column chromatogr- aphy and tabular chromatography ,and it was analysized with gas chromatography and mass spectroscopy (GC-MS).The major compositions were Bis(2-ethylhexyl)phthalate,Di-n-octyl phthalate,Dibutylphthalate,Campesterol,4-(octyloxy)-Benzenamine, (Z)-9-Octadecenamide and Limonene.