中文摘要：

上衣蛋白质(CP ) 基因从 11 的病毒的粒子被克隆并且定序在中国和 4 汉语从野柠檬植物收集的柠檬 tristeza 病毒(CTV ) 孤立分别地从栽培香甜的橘子和 pummelo 变化孤立。由分析并且比较 CP 基因的核苷酸和氨基酸序列， 11 野 CTV 孤立与 4 中国 CTV 被发现超过 92% 相同孤立， 21 异国情调的 CTV 从栽培柠檬孤立。从 91 ～ 100% CTV CP 基因，在野类型柠檬植物的序列通常是保存的井。基因进化分析显示 CP 基因的 GC% 是不到 AT% ，并且更多的转变比 transversion 在 CP 基因被发现， transition/transversion 比率在种类之中从 6.3 ～ 7.0 。替换频率在第三 codon 是最高的，由第一和第二 codon 列在后面。到同义的变化(dS ) 的非同义的变化(dN ) 的比率比 1 远低，建议 CP 基因可能经历了净化在进化的选择。种系发生的分析表明 11 CTV 在属于的中国野类型柠檬孤立不同的种系发生的簇，并且分享了有另外的栽培柠檬的更高的相同和 CTV 从不同国家孤立的更靠近的关系，它在 CTV 之中显示了复杂基因关系孤立。另外， CTV 与通常定位进一样的簇的类似的生物特征孤立。因此，结论被画那个致病力对 CTV 的进化和起源批评。

英文摘要：

The coat protein （CP） genes were cloned and sequenced from viral particles of 11 isolates of citrus tristeza virus （CTV） collected from wild citrus plants in China and 4 Chinese isolates from cultivated sweet orange and pummelo varieties, respectively. By analyzing and comparing the nucleotide and amino acid sequences of CP genes, the 11 wild CTV isolates were found over 92% identical with 4 Chinese CTV isolates and 21 exotic CTV isolates from cultivated citrus. From 91 to 100% of the CTV CP gene sequences in wild type citrus plants were generally well conserved. Genetic evolution analysis indicated that the GC% of the CP gene was less than AT%, and more transition were found in the CP genes than transversion with the transition/transversion ratio ranging from 6.3 to 7.0 among species. The substitution frequency was the highest at the third codon, followed by the first and second codon. The ratio of non-synonymous mutations （du） to synonymous mutations （ds） was far lower than 1, suggesting that the CP gene might have experienced purifying selection in the evolution. Phylogenetic analysis revealed that the 11 CTV isolates in Chinese wild type citrus belonged to different phylogenetic clusters, and shared higher homology and closer relationships with other cultivated citrus CTV isolates from different countries, which indicated complicated genetic relationships among the CTV isolates. In addition, CTV isolates with similar biological characteristics usually located into the same clusters. Therefore, the conclusion was drawn that pathogenicity was critical to evolution and origin of CTV.