桑树上新发生的细菌性枝枯病病原的研究

据病害症状、病原菌分离、纯化及致病性、生理生化特性、冰核活性（ＩＮＡ），血清学的试验结果，证明桑树枝枯病的病原细菌是一种丁香假单胞菌（Ｐｓｅｕｄｏｍｏｎａｓｓｙｒｉｎｇａｅ），具有冰核活性。它与桑细菌性疫病的病原细菌具有部分同源的血清学关系，但在发病症状及侵染部位，侵染时期等方面明显不同，所以认为桑细菌性枝枯病病原细菌可能是丁香假单胞菌组群中一个新的致病变种（Ｐａｔｈｏｖａｒ）。

STUDIES ON A NEW BACTERIAL BRANCH-WITHERING DISEASE OF MULBERRY

A new bacterial Branch-withering disease of mulberry was found in Shanxi Provincein 1988.The symptom was characterized as no bud germination or stunt growing,fol-lowed by bud withering.The disease occurs in early spring.The causal organism is iden-tified as Pseudomonas syringae with INA.But is different from P.syringae pv mori inpathogenicity.Whether it is a new pathovar of P.syringae is still under investigation.