我国不同地区禾谷缢管蚜种群感染RhPV的RT-PCR检测

禾谷缢管蚜病毒(RhPV)是一种寄生在禾谷缢管蚜体内的小RNA病毒。为了探讨RhPV在我国禾谷缢管蚜种群中的分布和感染情况,从我国11个省16个不同地区麦田采集禾谷缢管蚜,利用RT-PCR检测RhPV在不同种群共212个禾谷缢管蚜个体中的感染情况,并对获得的RhPV基因序列进行了差异比较和系统发育分析。结果表明,16个禾谷缢管蚜地理种群中均检测到了RhPV,感染率介于50%~100%之间。序列比对分析表明,克隆得到的RhPV基因片段在不同种群中非常保守,所有分析的蚜虫个体中仅得到6条不同的基因序列,这些序列与其他国家已经报道的RhPV序列相似性都在98%以上;系统发育分析表明,6条不同的RhPV基因序列可以分为2个亚进化枝,国外报道的两条RhPV相应序列构成其中的一个进化枝,本研究获得的6条序列构成另外一个进化枝。本研究所选用的基因片段能够准确检测RhPV在禾谷缢管蚜中的感染率,为进一步分析RhPV对禾谷缢管蚜的发育繁殖、行为、种群动态和种群微进化的影响奠定了基础。

Detection of Rhopalosiphum padi Virus (RhPV) in Rhopalosiphum padi Samples from Different Regions of China by RT-PCR

The bird cherry-oat aphid, Rhopalosiphum padi (L.) (Hemiptera: Aphididae), is one of the most economically important pests on triticeae crops. Rhopalosiphum padi virus (RhPV) is an insect RNA virus which can decrease the longevity and fecundity of infected aphid. To investigate the infection and distribution of RhPV in R.padi populations in China, 211 R.padi individuals were collected from 16 different regions of 11 provinces in China. RT-PCR was used to amplify RhPV gene sequences from the 212 R.padi individuals. The divergence and phylogenetic relationship was analyzed with gene sequences obtained from all the samples. The results showed that RhPV was detected in the 16 geographical populations of R.padi, with the infection rates ranging between 50% to 100%. The results of BLAST search in GenBank showed that the RhPV gene sequences amplified were relatively conserved among different populations, and only six different sequences were found. All the sequences obtained showed high similarity (>98%) with the corresponding RhPV sequences deposited in GenBank. Phylogenetic analysis of the 6 different RhPV sequences revealed that these sequences obtained in the study formed a cluster and those deposited in GenBank formed another cluster. In conclusion,the molecular method for detection RhPV in R.padi in current study can be used for further investigation of RhPV on development and reproduction, behaviour, population dynamics and population microevolution of R.padi.