首次发现巴西果胶杆菌(Pectobacterium brasiliense)引起甘薯茎腐病

<正>Dickeya和Pectobacterium属细菌的植物寄主广泛，包括十字花科、茄科、百合科、伞形花科和禾本科等科的农作物^1]，所引发的细菌性软腐病严重影响农作物的产量和品质，造成严重经济损失，威胁农业生产和粮食安全。Dickeya和Pectobacterium属不同种的菌株能侵染同一种植物，产生相似的病症。如已发现能侵染马铃薯并导致软腐病害的有D. solani、D. dianthicola、D. dadantii、D.chrysanthemi、D. zeae、P. versatile、P. carotovorum、P. brasiliense、P. atrosepticum、P. betavasculorum、P. parmentieri、P. parvum、P. peruviense、P. polaris、P. actinidiae和P. punjabense等种的细菌^2-3]。

First report of Pectobacterium brasiliense causing stem rot disease of sweet potato

The bacterial stem and root rot disease of sweet potato occurs in some regions of China and causes great economic losses. Dickeya dadantii is the known pathogen of this disease. We isolated pectin-degrading bacteria from diseased sweet potato plants grown in Jinhua, Zhejiang Province using the crystal violet pectate (CVP) medium. Inoculation of these bacterial isolates into stems of sweet potato seedlings caused weak symptoms of the stem rot disease. These bacterial isolates were identified as Pectobacterium brasiliense by multi-locus sequence (16S rRNA, dnaX, leuS and recA genes) analysis and PCR amplification using P. brasiliense-specific primers. Inoculation of this P. brasiliense pathogen caused weak potato blackleg disease. This is the first report of P. brasiliense causing the stem rot disease of sweet potato in the field.