Saedi D, Bruening G, Kado C I, Dutra J C
Infect Immun. 1979 Feb;23(2):298-304. doi: 10.1128/iai.23.2.298-304.1979.
Cowpea (Vigna sinensis) seedlings failed to develop tumors after being inoculated with crown gall bacteria (Agrobacterium tumefaciens) if, at times earlier than 1 day later, they were inoculated on the primary leaves with a cowpea mosaic virus that systemically infects them. Inoculation with buffer or with a virus that is restricted to a localized infection, or to which the cowpea is immune, did not interfere with the subsequent development of tumors. The virus infection did not appear to affect directly the titer of A. tumefaciens in the inoculation sites. Nor did mixing of virus particles with A. tumefaciens prevent subsequent appearance of tumors. The influence of virus infection extended across grafts (into tissue that is not susceptible to the virus) and there prevented tumor formation. The sap from infected plants, but not purified virus, decreased tumor formation on carrot disks. Systemic virus infection may induce in cowpeas a translocated substance that prevents tumor induction by A. tumefaciens.
如果在豇豆（Vigna sinensis）幼苗接种冠瘿病菌（根癌土壤杆菌，Agrobacterium tumefaciens）之前的1天内，用能使其发生系统感染的豇豆花叶病毒接种其初生叶，那么这些幼苗接种冠瘿病菌后不会形成肿瘤。用缓冲液接种，或用局限于局部感染的病毒接种，或用豇豆对其免疫的病毒接种，均不会干扰随后肿瘤的形成。病毒感染似乎并未直接影响接种部位根癌土壤杆菌的滴度。将病毒粒子与根癌土壤杆菌混合也不会阻止随后肿瘤的出现。病毒感染的影响可通过嫁接扩展到（进入对该病毒不敏感的组织）并在那里阻止肿瘤形成。受感染植株的汁液而非纯化病毒，可减少胡萝卜圆片上肿瘤的形成。系统的病毒感染可能会在豇豆中诱导一种可转运的物质，该物质可阻止根癌土壤杆菌诱导肿瘤。
