（1School of Biological Sciences and Technology，Liupanshui Normal University，Liupanshui 553004，Guizhou，China；2Science and Technology Bureau of Liupanshui，Liupanshui 553001，Guizhou，China）
Abstract：Abstract：Soft rot is one of the most serious diseases in konjac cultivation．To clarify the species andinfection characteristics of pathogens causing konjac soft rot in Liupanshui area，16 pathogenic bacteriastrains were isolated on disease materials from seven production areas．Based on morphological，16S rDNAsequence and biochemical analysis，the strains were identified as Pectinobacterium aroidearum and Dickeyafangzhongdai．Notably，P. aroidearum was the primary pathogenic species with a isolation rate of 81.25%．Pathogenicity identification showed that the two pathogens infect the konjac petioles and leaves faster than thecorm，and both pathogens cause soft rot in tomato，sweet potato，carrot，pumpkin，potato and radish．The cultivation and infection conditions indicated that D. fangzhongdai and P. aroidearum were rapidly proliferated and infected konjac within the range of 28-35 ℃ and 20-30 ℃，and optimal growth and infection temperature were 30 ℃ and 28 ℃，respectively．
