四川米易赛葵上粉虱传双生病毒的分子鉴定及复合侵染检测

Identification and detection of mix-infection of whitefly-transmitted geminiviruses on Malvastrum coromandelianum in Miyi County of Sichuan Province

为了明确四川米易赛葵上的双生病毒种类及复合侵染情况,基于滚环扩增PCR(RCA-PCR)技术,利用双生病毒DNA-A、DNA-B及卫星DNA的通用引物对四川米易表现黄脉症状的12个赛葵样品进行了检测,并对其序列进行分析。双生病毒的检出率高达92%;共检出云南赛葵黄脉病毒(Malvastrum yellow vein Yunnan virus,MYVYNV)、赛葵黄脉病毒(Malvastrum yellow vein virus,MYVV)及中国番茄黄化曲叶病毒(Tomato yellow leaf curl China virus,TYLCCNV)等3种双生病毒,复合侵染率高达67%;11个阳性样品中共检测到两类卫星DNAβ分子,分别与MYVYNV伴随的DNAβ(MYVYNB-[Y160],98.4%～98.7%)和MYVV伴随的DNAβ(MYVB-[Y197],98.5%～98.7%)的序列相似性最高;未扩增到DNA-B及DNAα分子。表明病毒DNA-A与卫星DNAβ以病害复合体形式存在,且DNAβ可伴随异源辅助病毒。

A set of universal primers of geminivirus which are able to detect the components of DNA-A,DNA-B and satellite DNA of geminivirus were used in rolling circle amplification and PCR（RCA-PCR） to determine the infection of geminivirus in twelve Malvastrum coromandelianum plants samples.These 12 M.coromandelianum samples were collect from Miyi County of Sichuan Province and all of them exhibit yellow vein symptoms.To further clarify the species and mix-infection of geminiviruses,the DNA sequences were analyzed.The results showed that geminiviruses were detected in 92% samples.These samples were infected by Malvastrum yellow vein Yunnan virus（MYVYNV）,Malvastrum yellow vein virus（MYVV） and Tomato yellow leaf curl China virus（TYLCCNV） and 67% samples were mix-infected by these viruses.Two types of satellite DNAβ molecules were found in 11 positive samples,and their nucleotide sequence are highly identity with either DNAβ associated with MYVYNV（MYVYNB-,98.4%-98.7%） or DNAβ associated with MYVV（MYVB-,98.5%-98.7%）.The DNA-B and satellite DNAα molecules were not detectable from these samples.These results suggested that bego moviruses DNA-A and their associated satellites exist as disease complex in these plants.The satellite DNAβ molecules can be associated with heterogeneous helper viruses.