Effect Of Dazomet And Sodium Hypochlorite On Soil Microflora And Growth And Development Of Watermelon In Continues Growing Plastic Channel

Continuous cropping obstacle is one of a serious problem in watermelon production. In order to overcome this problem, the best way is reasonable rotation with other crops. However, due to the limited rural land, the crop rotation is difficult to implement. Applying soil disinfectant is an effective measure to solve the problem of continuous cropping obstacle in watermelon.The test used dazomet and sodium hypochlorite as the soil disinfectants for soil treatments. Whereafter, we measured soil microfloras at different times, and the qualities and the yields of watermelon were also determined. On the other side, incidence rates and mortality rates were also recorded.The results showed as follows:1) Before applying dazomet and sodium hypochlorite, the microbial flora of each treatment was kept on a same level. After applied dazomet, the numbers of soil fungi, bacteria and actinomycetes were drastically reduced. As the watermelon growth, the above factors were increased. However, the application of sodium hypochlorite had no significant effect on soil microflora.2) In2014, the watermelon which treated with dazomet, the stem diameter、plant height are better than that of no-treated ones. As the same time, the higher concentrations of dazomet (15kg/mu20kg/mu,25kg/mu) used, the better to the growth of watermelon.On the contrary, the2013and2014tests had shown that applying sodium hypochlorite had no significant effect on plant height and stem diameter. It is ineffective to prevention continuous cropping obstacle to apply sodium hypochlorite as the soil disinfectants.3) In2014, both of the incidence rates and mortality rates were significantly reduced after applying dazomet. And the higher the concentration of dazomet used, the lower the incidence was measured. In contrast, applying sodium hypochlorite had no significant effects on continuous cropping obstacle.