A virus isolate collected in a commercial crop of St. Augustine grass
in Turmero, Aragua State, was mechanically inoculated to some differen
tial hosts for its identification The virus infected different sorghum
(Sorghum bicolor) cultivars, maize (Zea mays) and sugarcane (Saccharu
m officinarum) cvs CP-31294 and CP-31588, but it didn't infect oat (Av
ena sativa), barley (Hordeum vulgare), wheat (Triticum aestivum), john
songrass (Sorghum halepense), and some dicotyledonous species. The the
rmal inactivation point of the virus was 55-60 degrees C, the dilution
end point was 10(-3)-10(-1), and the longevity in vitro was 12-24 h a
t 27 degrees C. The virus was transmitted from sorghum to sorghum in a
non-persistent manner by the aphid Rhopalosiphum maidis, but it was n
ot transmitted through sorghum seed Electron microscopy revealed flexu
ous rod's 730-800 nm long. Citoplasmic inclusions of the pinwheel, scr
oll and laminated aggregates types were found in cells of maize infect
ed with the virus. It was distantly related to SCMV-A and MDMV-V, but
mere closely to SCMV-D when tested with antisera to the three strains
by double-diffusion tests. On the basis of all used identification cri
terions, the St. Augustine grass virus isolate corresponds to SCMV-D.
This is the first report of SCMV-D in Venezuela. S. secundatum is repo
rted, apparently, for the first time as a natural host of SCMV-D.