ABSTRACT
In this paper, the number of rhizosphere and non-rhizosphere microbial organisms of fusarium wilt resistant and susceptible watermelon under soil culture and soilless substrate culture was studied by traditional culture methods. The results showed that, the number of rhizoshpere microorganisms was significantly higher than non-rhizosphere, and the number was changed with the stage of watermelon grow, the number was the lowest in seedling stage and increased with the watermelon grow, and achieved highest at the flowering and fruiting stage, decreased with the watermelon ageing. The fusarium wilt resistant of watermelon was correspondence with number of rhizosphere bacteria; the number of rhizosphere bacteria of resistant watermelon was higher than that of susceptible watermelon in each stage under soil culture and soilless culture. The fusarium wilt resistant of watermelon is no correspondence with number of rhizosphere fungi and actinomycete. The number of non-rhizosphere microbial organisms was changed in a small range in the whole growing stage. The non-rhizosphere bacteria have no significant change in the whole stage under soil culture and increased quickly under soilless substrate culture and decreased at the later stage. The non-rhizosphere fungi and actinomycete reached highest at the later stage under soil culture or soilless sub-strate culture.