Isolation, Identification Of Ectomycorrhizal Fungi And The Mycorrhizal Formation Of Tissue Cultured Plantlets On Ostryopsis Davidiana

The ectomycorrhizal fungi from Ostryopsis davidiana were isolated and purified. The suspected ectomycorrhizal fungi strains were identified based on the analysis of ITS sequences. The atem segments with axillary buds of Ostryopsis davidiana were taken as the explants in the experiment. The sterilization of the explants, selection of basic medium, proliferation and rooting of Ostryopsis davidiana were studied. The tissue culture regeneration system were established. The growth-promoting Ostryopsis davidiana after inoculated Cg in differernt period were studied.The main results were as follows:(1) Twelve suspected ectomycorrhizal fungal isolates were obtained and identificated. Eight of twelve strains were ectomycorrhizal fungi. Of these ectomycorrhiza fungi, four species belonged to Basidiomycotina including Tomentella ldpidum, Tomentella ramosissima, Tomentella fuscocinerea and Lactarius pubescens, and four were all Cenococcum geophilum.(2) The optimal conditions of each tissue culture stage were established:the best way of sterilization was soaked in75%alcohol for30s, then treated in5%NaCIO for7min, the germination rate could reached to66%; The optimal basic medium was the WPM; The optimal proliferation medium for the buds was WPM+6-BA0.5mg/L+NAA0.03mg/L and the proliferation rate reached to436.7%; For rooting, the optimal medium was WPM+NAA0.2mg/L. The rooting rate was up to100.0%.(3) After inoculated CgO5and CgSO11for4months in the tissue culture bottles of Ostryopsis davidiana showed that the mycorrhizal formation rates of CgO5and CgSO11were73.3%and80.0%; The heights of mycorrhizal plantlets of Ostryopsis davidiana were respectively57.9%and55.6%higher than the control; The ground diameters were increased by32.7%and33.2%; The shoots dry weight were raised by65.5%and63.2%; The roots dry weight were raised by141.7%and136.5%; The total dry weights were increased by96.3%and93.0%; The root/shoot ratios were increased by46.3%and46.3%. After inoculated CgO5and CgSO11for5months to the plantlets of Ostryopsis davidiana after transplanting, the mycorrhizal formation rates of CgO5and CgSO11both were up to100.0%. The infection rates of CgO5and CgSO11on the Ostryopsis davidiana were49.5%and53.2%respectively; After inoculating CgO5and CgSO11, the heights of mycorrhizal plantlets of Ostryopsis davidiana were respectively105.0%and102.5%higher than the control. The ground diameters were increased by57.8%and44.8%; The shoots dry weight were raised by73.5%and71.0%; The roots dry weight were raised by183.3%and172.4%; The total dry weights were increased by120.9%and114.8%. The root/shoot ratios were increased by64.0%and60.0%. All of the results manifested that after inoculated Cg, the growth of host plants were improved definitely.