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通过Ｔｎ５诱变、缺失分析和标记置换构建了一个缺失了ｒｐｆＣ基因上游约０．８ｋｂ序列的水稻黄单胞菌水稻变种突变株，该突变株被命名为ＳＬ３７５１，在剪叶接种植株试验中，ＳＬ３７５１对水稻广桂１１０具有极弱的毒性，而在浸种和喷雾接种试验中它不致病．在剪叶时，该突变株能在广桂１１０叶片中繁殖到每叶含１０７菌落，这比野生型低两个数量级，ＳＬ３７５１能侵染水稻种子并在随后长成的植株中定殖．用突变株浸种处理广桂１１０种子，在温室生长植株的分蘖和抽穗期分别剪叶接种野生型菌株，接种１４ｄ后，处理植株的病斑长度分别对比对照植株的病斑长３９．０％和１８．６％．在温室条件下，ＳＬ３７５１预处理广桂１１０种子能使水稻细菌性条斑病的病情指数降低５．３，预效５４．６％．１９９６年晚造，经ＳＬ３７５１浸种处理过的小苗移栽到大田中，在植株分蘖早期喷雾接种野生型菌株后２０ｄ，处理植株的病情指数为９．１５，比对照植株低３．６８．突变株浸种处理对白叶枯病的防效为２８．７％．这表明本研究将是一种新的具有发展潜力的生物防治水稻细菌性病害方法
A T-mutant mutant of X. aeruginosa lacking about 0.8 kb upstream of the rpfC gene was constructed by Tn5 mutagenesis, deletion analysis and marker replacement. The mutant was named as SL3751. In the cut-leaf inoculation plant experiment, SL3751 is extremely toxic to rice grain Kwangui 110 and is not pathogenic in seed soaking and spray inoculation trials. At the time of leaf cutting, the mutant was capable of propagating in Kwangui 110 leaves to 107 colonies per leaf, two orders of magnitude less than the wild type. SL3751 was able to infect rice seeds and colonize the subsequent plants. The seeds of Guanggui 110 were soaked in the mutants and the wild-type strains were cut at the tillering stage and the heading stage of greenhouse plants respectively. After 14 days of inoculation, the lesion length of the treated plants was 39.0% longer than that of the control plants respectively 18.6%. Under greenhouse conditions, SL3751 pretreatment Kwangui 110 seeds can make the disease index of rice bacterial leaf streak reduce 5.3, pre-54.6%. On the evening of 1996, the seedlings treated with soaked seeds of SL3751 were transplanted into the field. The disease index of the treated plants was 9.15 20 d after spraying the wild type strain early tillering plants, which was 3.68 lower than that of the control plants. Mutant strain soaking treatment of bacterial blight control effect was 28.7%. This indicates that this study will be a new method for biological control of rice bacterial diseases with potential for development