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溪蜜柚是中国大陆柚类中的优质品种。近年来 ,在福建省的产地发现溪蜜柚叶片表现斑驳的病树 ,其叶片斑驳与柑桔黄龙病的叶片病状十分相似。据实验结果证明 :该病能通过病梢嫁接传染到柚和柑桔的健苗 ;在电镜下观察到病株韧皮部寄生着大量 BL Os,其形态和构造均与柑桔黄龙病病原 (L iberobacter asiaticum)相似 ;经PCR扩增与 Southern Blot分子杂交测定 ,表明该病原 DNA PCR产物与柑桔黄龙病病原 PCR产物之间具有很高的同源性。初步认为该病很可能是柑桔黄龙病引起的。为了进一步明确该病与柑桔黄龙病的关系 ,对病原 DNA片段进行扩增、克隆和序列分析 ,并与柑桔黄龙病病原基因相应序列进行比较 ,结果表明该病原与亚洲柑桔黄龙病病原 (L.asiaticum)相应基因序列的同源率达 94 .2 % ,而与非洲柑桔黄龙病病原 (L.africanum)的同源率仅为75 .0 %。进一步证明溪蜜柚叶片斑驳是柑桔黄龙病引起的 ,其病原是 L. asiaticum中的一个成员
Guanxi honey pomelo is a high-quality varieties of pomelo in mainland China. In recent years, the origin of Fujian Province found that Ying pomelo leaves mottled diseased trees, leaf mottling and citrus Huanglongbing leaf symptoms are very similar. According to the experimental results, it is proved that the disease can be transmitted to the healthy seedlings of pomelo and citrus by grafting, and the large number of BL Os parasitized by the phloem of the diseased plants is observed under the electron microscope. The morphology and structure of BL Os are associated with Liberobacter asiaticum). The results of PCR and Southern Blot hybridization showed that there was a high homology between the PCR product of the pathogen and the pathogenic PCR product of citrus Huanglongbing. The disease is likely to be caused by citrus Huanglongbing. In order to further clarify the relationship between the disease and citrus Huanglongbing, the DNA fragment of the pathogen was amplified, cloned and sequenced, and compared with the corresponding sequence of the pathogenic gene of citrus yellow dragon, the results showed that the pathogen and Citrus Huanglongbing pathogen (L.asiaticum) corresponding gene sequence homology rate of 94.2%, and the African citrus Huanglongbing pathogen (L.africanum) homology was only 75.0%. To further prove that the pomfret pummelo leaf mottled citrus Huanglongbing caused by the pathogen is a member of L. asiaticum