Abstract: A field experiment with diversity cultivation of konjac and maize was conducted in Fuyuan County of Yunnan Province to study the konjac’s soft rot disease incidence, plant growth, and isolation efficiency of Erwinia carotovora causing konjac’s soft rot. Among the test cultivation modes, konjac and maize rotation was most effective in controlling konjac’s soft rot disease, which could decrease the preliminary infection sources and delay the peak of disease incidence for one month. In the rotation field, intercropping maize with konjac decreased the disease severity by 59%, as compared with konjac monocropping, and the isolation efficiency of E. carotovora from the tuber of intercropped konjac was significantly lower than that of monocropped konjac. In intercropping system, there was a significant difference in konjac height but little difference in soft rot disease incidence among different cultivation lines. However, the isolation efficiency of E. carotovora from infected plant was significantly different, and there was a positive correlation between the isolation efficiency and the line distance. It was suggested that konjac and maize rotation combined with intercropping could be an efficient way for controlling konjac’s soft rot disease, and maize would be the physical barrier for the pathogen spread in intercropping system.

Key words: Bacillus subtilis, community composition, 16S rRNA gene, amplified ribosomal DNA restriction analysis (ARDRA).