Natural Infection of Broad Bean by Bean Common Mosaic Virus

Abstract

Severe mosaic symptoms were observed in a field of broad bean ( Vicia faba L. ) at the College of Agriculture Research and Experimental Station in Dirab area, Saudi Arabia, during January 1988. Out of 14 different test plant species inoculated with sap from infected plants, mosaic symptoms were observed on Vicia faba L., Phaseolus vulgaris L., and Pisum sativum L. . Local lesions were observed on Chenopodium amaranticolor Coste and Reyn . Physical properties of the infective sap were as follows : DEP was between 10-3 and 10-4, TIP was between 60 and 70 oC and LIV was between 3 and 4 days . Electron microscopic examination of grids prepared using the leaf dip method and negatively stained with 2 % phosphotungstic acid revealed elongated flexuous virus particles typical of potyviruses . A precipitation band was formed using Ouchterlony agar double diffusion test in Petri plates when sap from infected broad bean plants was treated with SDS and tested with BCMV antiserum . This is the first report of BCMV in Saudi Arabia.