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Bacterial canker is one of the most severe diseases on kiwifruit caused by Pseudomonas syringae pv.actinidiae.It has become an international pandemic and is threatening the sustainable development of kiwifruit production in all the main kiwi-growing regions all over the world.Presently, streptomycin has been the major bactericide for the control of kiwifruit canker, expecially in Anhui Province, one of the main kiwifruit production regions in China.However, till now, no studies on the baseline sensitivity to streptomycin of field isolates of P.syringae pv.actinidiae from China are available.During 2012-2013, a total of 102 single-colony P.syringae pv.actinidiae strains were isolated among which 36, 12, 13, 26 and 15 strains were from Yuexi, Jinzhai, Huoshan, Qianshan and Taihu county, respectively.All the generated P.syringae pv.actinidiae strains were confirmed by specific polymerase chain reaction (PCR) in which the isolated strains could produce a 280-bp fragment by using the specific primers PsaF1/R2, and followed by confirmation of pathogenicity assay, to fulfill Kochs postulates.In this study,sensitivity of 102 P.syringae pv.actinidiae strains to streptomycin was determined.The EC50 values for streptomycin in inhibiting bacterial growth of the these strains were 0.03 ~ 0.42 μg/ml with the average EC50 value of 0.12 ±0.06μg/ml.The baseline sensitivity curve was unimodal, representing range-of-variation factors of 14.0.There was no resistant subpopulation among the strains used in the study.Thus, these sensitivity data could be used as a baseline for monitoring the shift in sensitivity of P.syringae pv.actinidiae populations to streptomycin in Anhui Province.Continuous resistance monitoring of P.syringae pv.actinidiae populations to streptomycin should be carried out since it is a at-risk bactericide.