【摘要】 探究来自云南不同时间和不同地区的烟草扭脉病毒(TVDV)各分离物间rtp基因序列差异，分析烟草丛顶病近年在田间发生趋势减缓的原因.以2020—2022年从云南楚雄、大理、保山及红河采集的染病烟草样品为材料，对TVDV的rtp基因进行扩增和序列分析，共得到TVDV 7个不同分离物的rtp基因序列，长度均为2 172 nt,包含618 nt的cp基因及1 554 nt的rtd区；推导的TVDVRTP蛋白共编码722个氨基酸，其中包含CP蛋白的205个氨基酸，RTD的517个氨基酸.多重序列比对结果发现，获得的7个TVDV分离物与GenBank上登录的其他TVDV分离物间cp基因核苷酸序列一致性为98.71%～100%,不同TVDV分离物间CP蛋白的氨基酸序列一致性为98.05%～100%,存在4个氨基酸的差异.获得的7个TVDV分离物与GenBank数据库登录的其他TVDV分离物间rtd区核苷酸序列一致性为96.68%～99.81%, RTD蛋白的氨基酸序列一致性为96.52%～100%,存在39个氨基酸的差异.这些TVDV分离物rtp基因的变异可能会对TVDV的蚜虫传播效率产生影响，进而影响到烟草丛顶病在田间的发生与流行.更多还原

【Abstract】 In order to explore the variationsinthe readthrough protein gene(rtp gene) sequencesamong isolates of tobacco vein distorting virus(TVDV) collected at different times and from various regions of Yunnan Province, and analyze the factors contributing to the recent deceleration of tobacco bush top diseasein the field, the rtp gene sequences of TVDV was cloned and analyzed from the diseased tobacco samples collected from Chuxiong, Dali, Baoshan and HongheAutonomous Prefectures/City in Yunnan Province from 2020 to 2022. The rtp gene sequences of seven different TVDV isolates were obtained, all of them were 2 172 nucleotide(nt) in length, consisting of a 618-ntcp gene and 1 554-ntrtd domain. Consequently, the TVDV RTP protein has a total of 722 amino acids(aa), comprising 205 aa of CP protein and 517 aa of RTD. Multiple alignment analysis results showed that the nt sequence identities of the cp genebetween the seven TVDV isolates obtained in this study and the TVDV isolates registered in GenBank were 98.71%～100%. Similarly, the aa sequence identities of the CP protein among different TVDV isolates were 98.05%～100%, with four aavariations. The nt sequence identities of the rtddomain between the seven TVDV isolates obtained in this study and the TVDV isolates derived fromGenBankranged from 96.68% to 99.81%. Likewise, the aa sequence identities of their RTD domain were 96.52%～100%, with thirty-nine aa differences.The variation of rtp gene in these TVDV isolates may affect the efficiency of aphid transmission of TVDV, and thus affect the occurrence and prevalence of tobacco bush top disease in the field.更多还原