摘 要：
在完整的油菜植株上,利用喷叶法测定放线菌代谢物质对病毒病的治疗效果,以处理组的发病率此对照组减少的百分率表示疗效。从1958年到1962年先后测定6,376号次放线菌,找到不吸水灰色放线菌类羣(Actinomyces ahygro-scopicus Yen)的1695、3494、4084和4313四个菌株的代谢物质,在接种油菜花叶病毒(总6号)24小时后喷叶,有50%左右的治疗效果,接种前24小时喷叶有100%的防护效果。接种24小时后喷叶而未发病的植株叶内未能测出有侵染性病毒的存在。从喷药一次的效果来看,显然胜于0.5%2-硫尿嘧啶在油菜上的作用。1695、3494和4084三株放线菌发酵液的有效成分经15磅30分钟的处理后,在植株上测定效果,差异并不大。但是,所有有效浓度对植株均能引起不同程度的黄化等生理反应,使生长遭受一定程度的抑制,类似2-硫尿嘧啶所引起的生理反应。病毒与1695放线菌发酵液混合(1分钟),立即被钝化。发酵液中的有效成分能被叶细胞吸收,通过剪叶法及不同部位局部喷药及接种等初步证明,代榭物质昀有效成分运转的距离似乎极短。1695的发酵液在植株上的治疗效果常因接种与喷药相隔时间的长短而异。接种后3小时内喷的效果为100%,6小时降至90%,1—3天为25—45%,5—7天为5—10%。同时,在接种后3天内喷而发病的植株体内其病毒含量比对照少,3天以后喷的则此对照反而有增多的趋势。1695的发酵液在胶州白菜上对孤丁1号的治疗效果(接种后隔24小时喷)为92%,比崐山土种油菜上对总6号病毒的疗效高出三分之一。此种差异可能由于寄主植物的差异引起的。
译 名：
THE THERAPEUTIC AND PROTECTANT EFFECT OF METABOLITES OF SOME ACTINOMYCES ISOLATES ON INCIDENCE OF A MOSAIC VIRUS DISEASE OF RAPE(BRASSICA CHINENSIS L.)
作 者：
Chiu Wei-fan Wu Chien-an (Institute of Microbiology,Acad.Sinica)
摘 要：
During 1957 to 1962,isolates belonging to the Group Actinomyces ahygroscopicus Yen hadbeen tested for their therapeutic and protectant effect on the incidence of a rape mosaic dis-ease caused by a strain of Turnip Mosaic Virus.The experimental methods consisted ofspraying the testing rape plants with cultural filtrates of Actinomyces isolates before or afterinoculation with Turnip Mosaic Virus strain No.6 of this Laboratory,comparing the symptomsdeveloped and assaying the concentration of the Virus on leaves of Nicotiana tabacum var.Huangmiaoyu.As a result of testing 6,376 isolates,only four of them namely Nos.1695,3494,4084 and 4313 cured about 50 per cent of the treated plants,if the spraying was madenot later than 24 hours after inoculation.However,100 per cent of plants inoculated remainedhealthy,if the sprayig was made 24 hours before inoculation.No virus was detected intissues of rape plants which remained apparently healthy owing to the therapeutic treatment.The effective constituents of the cultural filtrates of isolates Nos.1695,3494 and 4048were apparently thermostable,since they were equally effective after being autoclaved under15 pounds pressure for 30 minutes.When any one of the cultural filtrates was mixed withthe virus in vitro,the latter was instantaneously inactivated.Demonstrations revealed thatthe effective constituents of the cultural filtrates were able to be absorbed by the rape plantcells,but translocated only a short distance.All effective concentrations of the cultural filtratesshowed more or less injurious effect to leaf tissues.Further tests made of isolate No.1695 showed that the therapeutic effect varied with thetime intervals between inoculation and spraying.100 per cent of plants were cured,if spray-ing was made within 3 hours after inoculation.Likewise 90 per cent of curing resulted within6 hours after inoculation,25-40 percent within 1-3 days and 5-10 per cent within 5-7 days.Experiments of curing the Kwuting disease of Chinese cabbage caused by K_(1-1) strain of TurnipMosaic Virus revealed that the therapeutic effect of these isolates was more effective onChinese cabbage than on rape.The writers were of the opinion that the variation of theeffectiveness was essentially due to hosts and not to strains of the virus.
