【摘要】 在北京地区水稻田分离到的水稻白叶枯细菌噬菌体有两种类型,Ⅰ型大斑(PK)和Ⅱ型小斑(PSS)。在进一步对噬菌体的寄主范围的测定表明,对非致病性的细菌以及植物病原细菌各属细菌如假单胞杆菌(Pseudomonas),棒形杆菌(Corynebacterium),土壤杆菌(Agrobacterium)均无溶菌作用,甚至对同属的黄单胞杆菌(Xanthomonas)的其他种细菌也无溶菌性,证明其寄主范围仅限于水稻白叶枯细菌。北京地区分离的各种噬菌体的专化性,经用全国23个省、市、自治区的137个白叶枯细菌菌株试验的结果,表明不同噬菌体存在着对不同细菌菌株侵染上明显差异,其中Ⅰ型(PK)只能侵染其中的72％菌株。而Ⅱ型中的(PSS)能侵染其中的92％的菌株,说明对寄主的专化性是不同的。以噬菌体侵染细菌,用“一步生长曲线”比较研究结果Ⅰ型噬菌体(PK)的潜育期短为40分钟,裂解量7。Ⅱ型(PSS)的潜育期较长,为70分钟,裂解量为46。在此基础上,应用噬菌体在水稻种子上增殖数量的测定可以反映出,水稻种子上具有活的白叶枯细菌的存在,这种方法灵敏度高,时间短,可用作稻种带菌检验之用。更多还原

【Abstract】 Studies on the host range of bacteriophage were conducted,it showsthat the phage of Xanthomonas oryzae is highly specific.It infects Xantho-monas oryzae only and leaves all other plant-pathogenic bacteria such asAgrobacterium,Corynebacterium,Pseudomonas,Bacillus,and saprophyticbacteria unattacked. The determination of specificity with 137 cultures of Xanthomonasoryzae isolated from 23 provinces throughout the country.We found thattype A is a phage with high specificity and type B is less specific.Thelater can infect 92％ of the cultures while the former only 92％. The studies of one-step growth curve indicated that the period ofincubation of type A was 40 minutes with a multiplication rate of 7 ti-mes and the period of incubation of type B 70 minutes,with a multipl-icationrate of 46 times. It seems that the bacteriophage type A with its high specificity canbe used as a tool to detect the presence of Xanthomonas oryzae from theseed of rice.更多还原