FIG 1.

Detection of Sf9 rhabdovirus RNA in insect cells exposed to Sf9 cell-conditioned medium. Cell lines obtained from the Agricultural Research Service (ARS) of the U.S. Department of Agriculture (USDA) were inoculated with Sf9 cell-conditioned medium and passaged three times at intervals of 72 h (P0, P1, and P2). Cell lines derived from Spodoptera exigua eggs (blue lines) were highly susceptible to Sf-RV. The ovary-derived Heliothis subflexa cell line (yellow line) was found to be endemically infected with Sf-RV at the start of the experiment (preinfected). The Helicoverpa zea ovary (dashed green line) or H. zea fat body-derived (solid green line) and H. virescens ovary (red line) cell lines did not support replication of Sf-RV.