AMV和WCMV复合侵染对本氏烟4种内源激素的影响

Effects of Alfalfa Mosaic Virus (AMV) and White Clover Mosaic Virus (WCMV) Co-infection on Four Endogenous Hormones in Nicotiana benthamiana

为明确苜蓿花叶病毒(AMV)和白三叶草花叶病毒(WCMV)混合接种协生作用以及对本氏烟中4种内源激素的影响,以接种0.02 mol/L磷酸盐缓冲溶液(PBS,pH 7.0)的本氏烟为空白对照,对AMV+WCMV(3∶1)混合接种本氏烟发病症状以及接种后不同时间本氏烟中病毒浓度和生长素(IAA)、玉米素核苷(ZR)、赤霉素(GA)、脱落酸(ABA)4种内源激素含量变化进行了研究。结果表明:AMV和WCMV混合接种后,主要表现为接种叶片褪绿、黄化、后期死亡脱落,新生叶变小、卷曲呈圆筒状、叶面呈现畸形皱缩,植株矮化;本氏烟叶中两种病毒浓度在接种后第10 d时最大,比单独接种AMV、WCMV的病毒浓度分别提高了1.70倍和1.48倍,症状加重,表明AMV和WCMV两种病毒存在复合侵染协生作用,WCMV为协生病毒,AMV为被协生病毒;AMV和WCMV混合接种后第2、6、10 d的IAA、ZR、GA含量均显著低于单独接种和对照,ABA含量则显著高于单独接种和对照,在接种后第10 d,混合接种处理的IAA、ZR、GA含量较CK分别降低了59.40%、63.39%、64.56%,而ABA含量提高了287.30%(P<0.01)。综上所述,AMV+WCMV(3∶1)混合接种使本氏烟症状表现加重,病毒浓度增加,显著降低IAA、ZR、GA含量,提高ABA含量。

In order to clarify the synergetic effect of Alfalfa mosaic virus(AMV)and White clover mosaic virus(WCMV)co-inoculation and their effects on four endogenous hormones in Nicotiana ben⁃thamiana,in this experiment,N.benthamiana inoculated with 0.02 mol/L pH 7.0 phosphate buffered solution(PBS)was used as the control,the disease symptoms and the changes of virus concentration,growth hormone(IAA),zeanoside(ZR),gibberellin(GA)and abolic acid(ABA)of Nicotiana benthami⁃ana after AMV+WCMV(3∶1)co-inoculation were studied.The results showed that after the AMV and WCMV co-inoculation,the main symptoms were chlorosis,yellowing,late death and falling off of inoculated leaves,small new leaves,curled in a cylindrical shape,deformed and shrunked leaf surface,and the plant dwarfism.The concentration of the two viruses in N.benthamiana leaves was the highest on the 10th day after inoculation.The virus concentration of AMV and WCMV was 1.70 times and 1.48 times higher than that of AMV and WCMV alone,and the symptoms of N.benthamiana were aggravated,indicating that AMV and WCMV had synergistic effect,WCMV was the synergetic virus and AMV was the passive synergetic virus.The contents of IAA,ZR and GA at 2nd,6th,and 10th day after AMV and WCMV coinoculation were significantly lower than those of single inoculation and control,while the content of ABA was significantly higher than that of single inoculation and control.Compared with CK,the contents of IAA,ZR and GA were decreased by 59.40%,63.39%,and 64.56%,respectively,while the content of ABA was increased by 287.30%(P<0.01).In summary,the co-inoculation with AMV+WCMV(3∶1)aggravated the symptoms of N.benthamiana,increased the virus concentration,significantly decreased the content of IAA,ZR and GA,and increased the content of ABA.