Study On Allelochemicals And Effects Of Rhizosphere Microorganism Of Pinus Tabulaeformis And Ostryopsis Davidiana In DaQingshan Mountains Of Inner Mongolia

In order to explore the coexistence mechanism of Pinus tabulaeformis and Ostryopsis davidiana in DaQingshan mountains degenenated ecosystem. The microorganism in rhizosphere soil and their allelopathic effects on P. tabulaeformis and O.davidiana bud seedling were studied. First, the preponderant microorganism was selected by a series of separation,purification and cultivation. Second, rhizosphere were cut thalli after cultivating,separating and purificating on solid culture medium, then the stain exudates were extracted by 95% acetone for indoor bioassay to P. tabulaeformis and O. davidiana bud seedling. At last, the components of those exudates which had obvious allelopathy were analyzed using gas chromatography-mass spectrometer. The results showed:(1) The tested strain exudates had no significant effect on the germination rate of P. tabulaeformis and O. davidiana seeds.(2) Fungi Z74,Z47,actinomycetes F48,F18,bacteria X62,X2 can promote P. tabulaeformis bud seedling growth, actinomycetes F5 can inhibit P. tabulaeformis bud seedling growth, fungi Z11,bacteria X62,X2,X101 can advance to O.davidiana bud seedling growth, and all of the tested actinomycetes restrain the growth ,they have significant compared to control.(3) Soil microorganism have high selectivity to P. tabulaeformis and O. davidiana allelopathy. Actinomycetes F48,F18,s exudates can significantly advance P. tabulaeformis Carr. bud seedling growth, however, it inhibits to the O. davidiana bud seedling growth strongly.(4) Exudates advancing P. tabulaeformis and O. davidiana bud seedling can be2-Hydroxy-2-methyl-succinic acid,bis-[2-oxo-2-phenyl-ethylester Lycoxanthin,Oleic acid,Pempidine,Colchicine,and 1,2-Benzenedicarboxylic acid, bis [2-methylpropyl] ester,Deoxyspergualin and Pempidine,pyrrolo,furan,tetrahydro matter through contrast to control strain exudates, but we need to validate more.