马铃薯X病毒和烟花叶病毒对于马铃薯Y病毒侵染酸浆的干扰作用的研究

STUDIES ON THE INTERFERENCE OF POTATO X VIRUS AND TOBACCO MOSAIC VIRUS WITH POTATO Y VIRUS IN THE LOCAL LESION RODUCTION ON PHYSALIS FLORIDANA

把含有烟花叶病毒(TMV)或马铃薯X病毒(PXV)的烟汁,或把含有提纯的TMV或PXV的缓冲液与含有马铃薯Y病毒(PYV)的烟汁混合接种酸浆上,PYV所引起的局部病斑比单独接种的较少。 PXV对于PYV侵染酸浆的干扰作用仅发生于两病毒同时接种于同一叶表面的情况下。TMV的干扰作用则也能发生于先接种或在接种PYV之后24小时内接种TMV或两病毒分别在叶面和叶背接种的情况下。 PXV的浓度与干扰作用成比例。经过紫外线照射或热处理而钝化了的PXV没有干扰作用。预先系统感染PXV趋于消除混合接种时PXV对PYV的干扰。无论所用的X病毒毒株是强的或弱的都存在这种关系。

In mixed inoculations,PXV and TMV,eitherin crude tobacco extract or under purified condi-tions,were almost equally effective in the inhibitionof local lesion production on Physalis floridanacaused by PYV. PXV interferrcd with PYV only when bothviruses were inoculated simultaneously on the sameleaf surface.With TMV,however,interference alsooccurred under conditions of PYV following TMVby unlimited length of time or TMV following PYVwithin 24 hours,and of the two viruses separatelyinoculated on the upper and lower surfaces of leaves. The degree of interference by PXV was directlyproportional to its concentration in the mixed ino-culum.Inactivation of PXV by ultraviolet lightirradiation or heat treatment of the virus-containingtobacco extract eliminated its interferring effect.In-hibition of PYV infection by PXV in a mixed ino-culum did not occur on plants previously systemi-cally infected with PXV.This relation appearedto hold both with mild strain and severe strain ofthe X virus used.