中国不同地区亚洲韧皮杆菌遗传多样性分析

 柑桔黄龙病是最严重的柑桔病害之一,现已威胁世界柑桔产业。已被证实在中国南部该病害通过嫁接和木虱传播。因此黄龙病的流行病学研究就显得尤为重要。本研究中,基于外膜蛋白(omp)基因的PCR-RFLP的方法被用来研究中国南部各柑桔主产区的亚洲韧皮部杆菌的遗传多样性。研究采用不同的限制性内切酶消化各地区的亚洲韧皮部杆菌的omp基因产生了不同的RFLP指纹图谱,并对各地亚洲韧皮部杆菌的omp基因进行克隆测序然后构建系统发育树。结果显示:中国不同地理区域的亚洲韧皮部杆菌具有一定的遗传多样性,即便在某一特定的地区也有一定的差异。序列分析显示中国地区的亚洲韧皮部杆菌有很高的同源性。这些结果对揭示中国柑桔黄龙病的流行病学及制定科学有效的防治策略具有一定的指导意义。

Genetic diversity of Candidates Liberibacter asiaticus isolates from different geographical regions in China

Citrus Huanglongbing (HLB) is one of the most destructive diseases. HLB has been demonstrated grafting transmissibility via infected citrus scion and psyllids in Southern China, therefore, it is important to investigate the epidemiology of HLB disease. The study on genetic diversity was conducted by using PCR-RFLP based on the outer membrane protein gene (omp) sequences. The amplicons of Candidatus Liberibacter asia-ticu (Las) were digested with different restrictive enzymes. The difference of restriction patterns show that Ca. L. asiaticus might comprise several different omp polymorphism even within a given region. DNA sequences and the deduced amino acid sequences of omp gene were compared to those in GenBank database with BLAST and the results were used to construct phylogenetic tree. It was showed that the omp gene of Ca. L. asiaticus from China were highly homogeneous, but other Candidatus Liberibacter species were not introduced or developed in China so far. The result is important to explore HLB disease epidemiology and helpful to develop more efficient control methods.