Authors
Jorge M.
Vivanco
,
The Pennsylvania State University, Department of Plant Pathology and Biotechnology Institute, University Park 16802
;
Maddalena
Querci
,
International Potato Center, Pathology Department
; and
Luis F.
Salazar
,
International Potato Center, Pathology Department Lima 12, Peru
ABSTRACT
Extracts of Mirabilis jalapa (Nyctaginaceae), containing a ribosome inactivating protein (RIP) called Mirabilis antiviral protein (MAP), were tested against infection by potato virus X, potato virus Y, potato leaf roll virus, and potato spindle tuber viroid. Root extracts of M. jalapa sprayed on test plants 24 h before virus or viroid inoculation inhibited infection by almost 100%, as corroborated by infectivity assays and the nucleic acid spot hybridization test. Antiviral activity of MAP extracts was observed against mechanically transmitted viruses but not against aphid-transmitted viruses. Purified MAP showed the same antiviral effect as the crude extracts.
