Genetic characterization and classification of two phytoplasmas associated with spartium witches’-broom disease
Genetic characterization and classification of two phytoplasmas associated with spartium witches’-broom disease
复制标题
两种与斯巴蒂姆扫帚病相关的植原体的遗传特征和分类
DOI：
10.1094/pd-80-0365
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发表时间：
1996
期刊：
影响因子：
--
通讯作者：
E. Seemüller
中科院分区：
文献类型：
--
作者：
C. Marcone;A. Ragozzino;B. Schneider;U. Lauer;C. Smart;E. Seemüller
在植物的西班牙扫帚（Spartium junceum）的病因不确定的女巫的扫帚病的影响，植物病原植原体荧光和扫描电子显微镜检测。限制性片段长度多态性（RFLP）分析的核糖体DNA，聚合酶链反应（PCR）-通过通用植原体引物扩增，揭示了两种不同的植原体存在于植物具有相似的症状。不太经常检测到的植原体有相同的RFLP图谱榆树黄化植原体，而流行的代理人有一个RFLP图谱相似的植原体在苹果增殖株集群。16SrDNA序列分析表明，目前流行的Spartium witches '-broom植原体是苹果增殖株系簇的一个成员，但该菌与其他簇成员有明显的区别。通用的，组和病原体特异性rDNA引物，病原体检测到大多数症状的植物。当用通用引物获得的rDNA片段用组特异性引物或病原特异性引物重新扩增时，在直接PCR中测试为阴性的植物产生扩增产物。巢式PCR检测也表明，大多数的植物检查双重感染两种植原体直接PCR检测。在受感染的植物中，这些生物之一是占主导地位的，很容易通过直接PCR检测，而其他发生在低数量，只能通过巢式PCR鉴定。
In plants of Spanish broom (Spartium junceum) affected by an etiologically uncertain witches'-broom disease, plant-pathogenic phytoplasmas were detected by fluorescence and scanning electron microscopy. Restriction fragment length polymorphism (RFLP) analysis of ribosomal DNA, polymerase chain reaction (PCR)-amplified by means of universal phytoplasma primers, revealed two different phytoplasmas present in plants with similar symptoms. The less frequently detected phytoplasma had the same RFLP profile as elm yellows phytoplasmas, whereas the prevalent agent had an RFLP profile similar to that of phytoplasmas in the apple proliferation strain cluster. Sequence analysis of 16S rDNA confirmed that the prevalent Spartium witches'-broom phytoplasma is a member of the apple proliferation strain cluster, but this organism is distinctly different from other cluster members. With universal, group- and pathogen-specific rDNA primers, the causal agents were detected in most symptomatic plants. The plants testing negatively in direct PCR yielded an amplification product when the rDNA fragment obtained with universal primers was re-amplified with group- or pathogen-specific primers. The nested-PCR assay also revealed that most of the plants examined were doubly infected with the two phytoplasmas detected by direct PCR. In the infected plants, one of these organisms was predominant and readily detectable by direct PCR while the other occurred in low numbers and could only be identified by nested PCR.