几种化学药物对柑桔裂皮病类病毒感染和复制的影响

经柑桔裂皮病类病毒(Citrus exocortis viroid,简称CEV)感染后的指示植物爪哇三七(Cynura aurantiaca),分别施用不同浓度的赤霉素(5ppm,10ppm,50ppm,100ppm,200ppm)、萘(100ppm,300ppm)、5-氟尿嘧啶(0.5mg/L,1mg/L,2mg/L)溶液,其相对感染指数(Relative infectivity index)均有程度不同的改变。抽提叶片核酸,经5％双向聚丙烯酰胺凝胶电泳(PAGE)-银染色法结合凝胶扫描技术确定CEV浓度,辅以点杂交方法定性,观察到施用赤霉素组CEV浓度增高,施用萘组和5-氟尿嘧啶组CEV浓度均降低。用无性繁殖的柑桔苗作材料,CEV感染后分别施用50ppm赤霉素、300ppm萘、1mg/L 5-氟尿嘧啶溶液,用相同的分析方法,得到了与爪哇三七一致的结果。讨论了这三种药物影响CEV复制的意义。

Effect of Some Chemicals on Infectivity and Replication of Citrus Exocortis Viroid

Gynura aurantiaca plants infected by citrus exocortis viroid (i.e. CEV) were applied in different concentrations of exogennous gibberellin (GA,5ppm, 10ppm, 50ppm, 100ppm, 200ppm), n(?)phthalen (Nal., 100ppm, 300ppm), 5-flurouracil (5-FU, 0.5mg/L, 1mg/L, 2mg/L) solutions respectively. It was found that the relative infectivity indexes of plants had to some extent been changed. Nucleic acids of young leaves were extracted and subjected to 5% bidirectional polyacrylamide gel electrophoresis (PAGE) followed by silver staining, CEV concentration was determined by using the gel scanning technique, companied with dot-blot hybridization. It was observed that CEV concentration had increased in applied GA group but decreased in applied Nal. group and in applied 5-FU group. Similarly, cloned citrus seedlings were applied by 50ppm C-A, 300ppm Nal., 1mg/L 5-FU respectively after CEV inoculation. The result is the same. The significance about the effect of the three kinds of drug on CEV replication was discussed.