致病的

A cross was made between two isolates of Magnaporthe grisea, CH63 and TH16. A total of 78 ascospore isolates were tested for pathogenicity on 36 rice varieties. The 71 pathotypes were clearly observed in the sexual progeny.

报导了两个稻瘟菌株CH63和TH16的杂交后代在36个水稻品种上的致病性分离、遗传分析以及无毒基因组成的分析结果。78个子囊孢子菌株中呈现显著的致病性分离，共出现71种致病类型，在不同品种上分别出现1：1、1：3、3：1、1：7、1：15和15：1等的无毒性／毒性分离，表明供试菌株对不同品种的无毒性／毒性是一个或多个基因控制的。

Preventing and controlling crown gall disease applied the early biological controls strain K84, itself did not have the pathogenicity, its plasmid may synthesize one kind of bacteriocin Agrocin84, may suppress many pathogenic strains, but did not have pathogenicity to non-pathogenic strain .

防治根癌病应用较早的生防菌株是K84，本身无致病性，它的质粒可以合成一种细菌素Agrocin84，可以抑制很多有致病性的菌株，而对非致病性的菌株则无影响。

The 2b protein encoded by Cucumber mosaic virus plays an important pathogenicity role in many solanaceous hosts, but mechanism of inducing disease is still unknown.

黄瓜花叶病毒(Cucumber mosaic virus，CMV)2b蛋白作为重要致病因子的角色在茄科模式植物上已为广泛描述，但其致病机理尚未廓清。

Isolates from watermelon-growing areas were classified into 3 races like race 0, race 1 and race 2 which were 8 (17.4), 30 (65.2), and 8 (17.4%), respectively. Pathogenecity of race 0 isolates are weakest which only make Sugar Baby susceptible; isolates of race 1 are intermediately pathogenetic, they make Sugar Baby and Charleston susceptible Gray but Calhoun Gray resistant; isolates belonging to race 2 possess the strongest pathogenecity, which make 3 hosts susceptible. Isolates of race 0 mainly distribute over the central and southern Hebei province, whereas race 2 cover the middle and north of Hebei, isolates of race 1 exist in the whole watermelon-growing areas in Hebei province.

根据鉴别寄主对供试菌系的抗感反应，将46个西瓜枯萎病菌系划分为0号、1号和2号3个不同的生理小种，分别包括8，30和8个菌系，占供试菌系的17.4%、65.2%和17.4%；0号生理小种菌系致病性最弱，仅使品种Sugar Baby感病，以冀中和冀南居多；1号生理小种菌系致病力中等，使鉴别寄主Sugar Baby和Charleston Gray感病，而使Calhoun Gray抗病，分布在整个河北省西瓜种植区；2号生理小种的菌系致病力最强，使3个鉴别寄主均能感病，主要分布在冀中和冀北。

The new chimeric infectious DNA clone and its derived, a virulent chimeric virus are constructed from the nonpathogenic PCV1 in which the immunogenic ORF gene of the pathogenic PCV2 replaces a gene of the nonpathogenic PCV1, preferably in the same position.

所述新型嵌合的传染性DNA克隆及其衍生的有毒力的嵌合病毒是用非致病性PCV1构建的，其中，致病性PCV2的免疫原性ORF基因取代了非致病性PCV1的基因，优选是在相同的位置上取代。

The results revealed that there was nosignificant difference between the symptoms produced by the mutant and thewild type strain by directly injecting the bacteria into mature turnip leaves,however,the mutant was nonpathogenic by inoculations with leaf-clippingand-spraying methods.

应用不同的接种方法对胞外多糖突变体的致病性进行了分析，发现突变体通过注射接种仍能产生与野生型相同症状，但通过喷雾和剪叶接种却完全丧失了致病能力，说明甘蓝黑腐病菌产生的胞外多糖可能在致病过程的早期阶段起作用，但对症状的产生不是必须的。

Methods Real-time PCR, using the primer-probe specific for the yst gene, was applied to detect the pathogenic （7 serotypes） and nonpathogenic （ 5 serotypes） Yersinia enterocolitica, other species of Yersinia （8 types）, and other enteric bacteria （8 types）.

应用针对致病性小肠结肠炎耶尔森菌染色体上yst基因而设计的特异引物和探针进行实时定量聚合酶链反应，检测致病性（7种血清型）和非致病性（5种）小肠结肠炎耶尔森菌、耶尔森菌属内的其他菌种（8种）及其他肠道细菌（8种）。

Systematic infection of mice is used as a model to test the virulence of several mutants. According with their ability to form hyphae, nonfilamentous mutant is avirulent, and hyphae defective mutants have decreased virulence.

用系统感染小鼠模型分析这些突变株的致病能力，同它们形成菌丝的能力相一致，野生菌的致病能力最强，形成菌丝弱的突变株致病能力也减弱，不能形成菌丝的cph1 efg1突变株和crk1则无毒性。

The results indicate that the presence of GSH increased the expression of exoY、exoS、phzA1 and gacA,while no difference was observed with others virulence factor genes tested.PAO1 produced markedly less pyocyanin than the wild type strain PAOIP＜0.01Treating with GSH, the PCN production of PAOI(△gshB was increased from 0.47μg/mL to 1.73μg/mL (P＜0.01),the PCN production of PAO1 increased from 1.3μg/mL to 1.9μg/mL(P＜0.05),this result indicates that GSH upregulates PCN production.

结果发现，GSH对启动子库中exoS、exoY、phzA1和gacA等致病性因子的表达有促进作用，对其余测试过的致病性因子则没有明显影响；铜绿假单胞菌分泌的重要致病因子绿脓菌素(pyocyanin，PCN)的含量，在PAO1中远低于PAO1P＜0.01加入GSH后，PCN平均含量在PAO1(△gshB中从0.47μg/mL提高到1.73μg/mL，差异十分显著(P＜0.01)，在PAO1中从1.3μg/mL提高到1.9μg/mL，差异显著(P＜0.05)，表明GSH对铜绿假单胞菌生产PCN有促进作用。

It was showed that the growth speed of hypha, sclerotinia production and the pathogenicity of strains had little relation with host and geographical location. The ability of oxalic acid production of strains had positive relation with the pathogenicity. In order to study the nutrition aptness, 8 kinds of culture mediums were tested and the result showed that S.

sclerotinia不同菌株菌丝的生长速度、菌核产量、致病力与其地理来源和寄主来源关系不大，对12个代表菌株的草酸产生能力的测定表明，菌株的草酸产生能力和病菌的致病性基本呈正相关，致病力较强的菌株草酸产生能力较强；采用8种培养基对代表菌株营养条件进行了研究，结果表明核盘菌S。

Breath, muscle contraction of the buttocks; arch body, as far as possible to hold his head, right leg straight towards the ceiling (peg-leg knee in order to avoid muscle tension).

呼气，收缩臀部肌肉；拱起身体，尽量抬起头来，右腿伸直朝向天花板（膝微屈，以避免肌肉紧张）。

The cost of moving grain food products was unchanged from May, but year over year are up 8%.

粮食产品的运输费用与5月份相比没有变化，但却比去年同期高8％。