Some properties of celery yellow vein, a virus serologically related to tomato black ring virus

Abstract

SUMMARYA virus consistently isolated from celery plants showing conspicuous yellow vein symptoms readily infected healthy celery plants by sap inoculation, grafting or planting in infested field soil, but failed to induce the field symptoms. This virus, which was named celery yellow vein (CYVV), was cultured in Nicotiana clevelandii and assayed in Gomphrena globosa or Chenopodium amaranticolor. It infected sixty‐seven of 119 plant species tested, but was eliminated from tobacco plants grown at 37°C. for 3–5 weeks.In N. clevelandii sap, CYVV was still infective after dilution to 1/5000, heating to 62·5°C. for 10 min., or storage at c. 18°C. for 14 days. CYVV was best purified and concentrated by differential centrifugation of extracts from infected N. clevelandii using butanol + phosphate buffer. Such preparations contained 'spherical' particles c. 29 mμ diameter, produced specific zones in density‐gradient centrifugation, reacted specifically in serological tests, and contained major and minor components with sedimentation coefficients of 125S and 96S respectively.Comparison of host range, properties in vitro, protection tests in plants, and serological relationships showed that CYVV was a serotype of tomato black ring virus, but was more closely related to the lettuce ringspot than to either the tomato black ring or beet ringspot strains.