低温对黄瓜花叶病毒CMV-BG株系2b基因多态性的影响  

Effect of low temperature on the polymorphism of CMV-BG 2b gene

作　　者：张兴桃[1] 温国蕾[1] 王晓丹[1] 赵爽[1] 庄木[2] 李艳红[1] 

机构地区：[1]首都师范大学生命科学学院 [2]中国农业科学院蔬菜花卉研究所,北京100081

出　　处：《植物病理学报》2008年第1期51-57,共7页Acta Phytopathologica Sinica

基　　金：北京科技新星计划项目(H013610020112)

摘　　要：本文将黄瓜花叶病毒CMV-BG株系侵染普通烟草的不同单株后,放在不同温度下培养,30d后对接种植株症状进行对比观察,并对2b基因表达进行了检测及其序列测定分析。结果表明:被CMV-BG株系侵染的植株在低温条件下,植株新生的大部分叶片严重畸形,而CMV-BG株系2b基因的表达与不同温度条件没有相关性;CMV2b基因序列与源分离物CMV-BG序列相比发生了较明显的变异,它们作为一组序列与分离物SF/GF/SY等的相似性甚至高于源BG序列;此外,尽管来自2组植物中的病毒序列变化均未表现正选择(positive selection),但来自低温培养的侵染植株的2b基因的多态性明显高于常温条件培养的植株,发生非同义突变的位点数目也高于同义突变的位点数目。因此认为,低温有助于加强CMV-BG株系2b基因的多态性。CMV-BG infected tobacco （Nicotiana tabacum var. Samsun NN） individuals were cultured under two different temperature conditions. The virus symptom, 2b gene expression and 2b gene sequence were analysed. The results showed that the symptom was much more serious on the plants under low temperature than normal conditions. The CMV-BG 2b gene sequence changed obviously and intricately, and expressed more close relationship with other CMV isolate （SF/GF/SY）. In addition, although no positive selection site was found from all the clones, CMV-BG 2b gene polymorphism was higher in the plants cultured at low-temperature, and the non-synonymous mutation was also more than synonymous mutation in this group. Thus, the low temperature could enhance the 2b gene polymorphism of CMV-BG.

关 键 词：黄瓜花叶病毒CMV-BG株系 2b基因多态性 低温 

分 类 号：S432.41[农业科学—植物病理学]