白花蛇舌草抗烟草花叶病毒作用机理的研究

目的]研究白花蛇舌草提取液对烟草花叶病毒（TMV）的抑制作用及其防治效果,为植物源抗病毒类生物农药的研制提供依据。方法]以心叶烟和K326为试验材料,采用常规摩擦接种,分别于接种病毒前24h和接种后24h分别喷施白花蛇舌草10倍液;接种处理3～5d后,调查枯斑数量,计算枯斑抑制率;普通烟接种处理后调查病情指数、计算防效;采用间接ELISA法4]测定各处理的病毒浓度;将提纯的TMV与白花蛇舌草10倍液等体积混合不同时间后,采用负染法在电镜下观察病毒粒子的形态变化。结果]对心叶烟的抑制率为84.6%,对系统寄主K326的防效为76.6%;在接种病毒前24h喷施药剂,枯斑抑制率和对系统寄主的防效分别为62.2%和61.5%;接种病毒后24h喷药试验结果表明,药剂能抑制植株体内病毒的增殖;电镜观察结果表明,病毒粒子有断裂现象,混合时间越长,破坏作用越强。结论]白花蛇舌草对TMV还具有较强的体外抑制作用,作用时间越长,抑制率越高。

Research on the Resistant Mechanism of the Herba hedyotis diffusae Willd to Tobacco Mosaic Virus

Objective] The basis of the development of biological pesticides of anti-virus provided through the research on the inhibition and control effect of the extract from plant on tobacco mosaic virus(TMV).Method] The 10 times' extract of Oldenlandia was sprayed on tobacco leaf in the 24th hour before and after the leaf of tobacco variety,Xinyeyan and K326 as testing material,was infected by TMV with conventional method of mechanical inoculation.The number of dried spot was counted in the 3rd-5th day after ino...