Effect Of VAM Fungus On The Growth Of Flue-cured Tobacco And Micro-ecological Environment Of Flue-cured Tobacco Rhizosphere

The present experiment studied the effect of VAM fungus on the growth of Flue-cured tobacco and micro-ecological environment of Flue-cured tobacco rhizosphere. Tape of NC-82 Flue-cured tobaccos in sterilized red soil (pH5.6) was inoculated with two strains of Glomus mosseae and Glomus versiforme .Research was focused on the total number of microbial population .physiological group of microbianism and Microbial biomass .Following are the main results:1 After Flue-cured tobaccos forming mycorrhiza with G.M and G.V , It promoted the drought resistance and increased the products of Flue-cured tobaccos. Compared with the control ,They decreased the growth time by 11 and 8 days; The contents of P,K,N in tobacco leaves were increased by 30.6% > 18.3 %^ 10.2%, 22.5 %^ 13.9%, 4.8% individually; The dry weight of single tobacco leaf (g/plant) and root (g/plant) were increased by 35.42 % ?39.49 %, 22.01 % ^ 18.27 % respectively. The total sugar content of the leaf was also remarkablely improved (p<0.05).2 The results showed that 2 VAM fungi tested had a good symbiotic relationship with roots of Flue-cured tobacco.The incidences of infection were both over 80%.However,there were significant differences in the effectiveness between the 2 VAM fungi. Glomus mosseae was more efficient than Glomus versiforme. The P,K,N and the total sugar and in tobacco leaves were increased by 6.7 % ^ 4. 3 % ^ 4. 5 % N 5. 53 %. The dry weight of single tobacco leaf (g/plant) and root (g/plant) were increased by 11. 02 % > 17.95%.3 In flue-cured tobacco rhizosphere.the infection of 2 VAM fungus induced thegreater change of microbial population and biomass. At the first sampling, the total number of bacteria in the inoculation treatment condition were slightly less than that in control condition, but the difference was unstriking(P>0.05); At the second sampling,the total number of bacteria hi the inoculation treatmenr condition were much less than that of control condition (P<0.05). At the later two sampling times, the total number of bacteria in the control condition were extremely more than that of the noninoculation treatment (P Aerobic-Cellulose decomplosing-bacterium > ammonifiers and N-fixer in root zone variated as that of bacteria. The total number of fungi were decreased slightly in the whole growing period of Flue-cured tobaccos, and extremely less than that of the noninoculation treatment ( P<0. 05 ) during the last measuring. Biomass was increased in the whole growing period of Flue-cured tobaccos.4 After Flue-cured tobaccos forming mycorrhiza with G. M and G. V, It improved the micro-ecological environment in the soil of Flue-cured tobaccos rhizosphere.The content of available N(mg/kg) ,available P(mg/kg) , available K(mg/kg) and O.M (g/kg) increased 25. 49%, 15.71%, 21.01%, 16.5%, 13.72%, 14.47%, 14.81%, 13.4% respectively. The productivity of soil were promoted effectively for the accumulated of the soil nutrient content...