Research on dynamic change of tobacco soil microbes in Dali

Tobacco rhizosphere and non-rhizosphere microbes,s dynamic changes were studied using microbial culture plate at six different tobacco planting regions in Dali in order to identify change trends of soil microbes in flue-cured tobacco growing season.Soil nourishing ingredients were also analyzed.Results showed that little bacteria and fungi in rosette stage were observed in both rhizosphere and non-rhizosphere soil,but the number of bacteria reached peak at maturity or late-curing stage,while fungi reach peak at rapid-growth or maturity stage.The largest number of actinomycosis appeared in rosette-stage,and the number of rhizosphere soil actinomycosis was slightly greater than that of non-rhizosphere soil.The number of actinomycetes quantity was significantly correlated to organic matter and available nitrogen in rhizosphere and non-rhizosphere soil,especially correlation between organic matter and actinomycetes.There was significant negative correlation between rhizosphere soil bacteria and available nitrogen,available phosphorus and potassium.Therefore,it is beneficial to keep proper nutrition in soil for controling bacterial diseases.