Effects Of Mycorrhizal Fungal On Growth Status Of Seedings In Karst Areas

Abstract The potted seedlings of Cupressus duclouxiana, Catalpa bungei and Pteroceltis tatarinowii were tested to study their characteristics of response under three different moisture content conditions, such as, normal moisture(25%-30%), moderate drought(15%-20%) and severe drought(5%-10%).biomass,root morphology and concentrations of nitrogen, phosphorus ,calcium and magnesium seedings were measured after 150 days. Accordingly, four inoculated groups were the control group(A), VAM group(B), ectomycorrhizal(C) and mixture group(D, VAM+Ectomycorrhiza).the results showed that:(1) After the seedlings was inoculated with mycorrhizal fungi, the colonization rate of C. duclouxiana and Catalpa bungei have an obvious effect on effect, biomass of above-ground and under-ground was increased and the effect of the mixed inoculation of C. duclouxiana was most significant,thus the effect of B of Catalpa bungei is most significant in Sterilized soil conditions under normal moisture and moderate drought after inoculated mycorrhizal fungi. the performance of nature soil and sterilized soil are same compared sterilized soil,but the effect of nature soil is not obvious by sterilized soil.(2) whether normal moisture or mediate drought,N and P content in roots and leaves of C. duclouxiana under inoculated treatment were higher than controled treatment. The N content of roots was respectively increased significantly 65.4%,118.2% and 117.7% in B, C, and D inoculated treatment under normal moisture. There were no significant in leaves between inoculated treatment and controlled treatment about N content. The P content in C, and D inoculated treatment were higher than that in controlled treatment.the significant difference about P content was indicated in D inoculated treatment. the N,P content in leaves and fine root of Catalpa bungei increased 9.1%～36.6% in B and D, there were no effect between C and A. Under mediate drought, there was significant difference between the treatment of B,D and A about N content in roots,but signifecant difference between C,D and A in leaves. And there was only insignificant difference between the treatment of C,D and A about P content in roots and leaves,increased 26.1% and 35.4%. but The treatment of B,C and D assumed significance differences with A in phosphorus concentration of leaf. Cupressus duclouxiana and Catalpa bungei were no obvious rule in leaves,root and stem between inoculated treatment and controlled treatment about Ca,Mg content under three different moisture content conditions.the performance of nature soil and sterilized soil are same compared sterilized soil,but the effect of nature soil is not obvious by sterilized soil.(3) And after mycorrhizal fungi vaccination,average diameter,total length,surface area and volume of C. duclouxiana showed increasing trend. and basically showed D>C>B.After inoculated VAM,biomass and root morphology of Catalpa bungei assumed significance differences with the control group,there was no effect about ectomycorrhizal treatment and controlled treatment.Under severe drought condition, the mycorrhizal fungi did not affected the plant biomass, nutrient content, and root morphology. the performance of nature soil and sterilized soil are same compared sterilized soil ,but the effect of nature soil is not obvious by sterilized soil.In brief, except for under severe drought condition, the mycorrhizal fungi would improve nutrient absorption and increased the biomass and benefit for enhancing survival rate of C. duclouxiana and Catalpa bungei.