Technical Abstract: The status of sugarcane yellow leaf virus (SCYLV) infection was determined in Saccharum clones maintained in field plots at the World Collection of Sugarcane and Related Grasses at the USDA-ARS Subtropical Horticultural Research Station at Miami, Florida to identify putative resistant and susceptible clones. SCYLV infected clones were considered susceptible and virus-free clones were assumed to be putatively resistant to SCYLV. Five leaves were collected from each clone from different plants in the 3 m plot. The SCYLV infection status was determined by the tissue blot immunoassay. The incidence of SCYLV infection varied among Saccharum spp. The incidence of SCYLV was 5.6 % for 252 S. spontaneum clones, 12.7 % for 55 S. barberi clones, 45.9 % for 37 S. sinense clones, 60.0 % for 55 S. robustum clones and 78.2 % for 325 S. officinarum clones evaluated. Of 175 Saccharum hybrid clones 70.9 % were infected. Several clones (Bandejarmain Hitan, Chunnee, Co 213, Co 285, POJ 100, POJ 213, and POJ 2878) that were used early in breeding programs were SCYLV infected; whereas, clones, Kassoer, Co 206, Co 281 and POJ 1499 were virus free. Both NCo 310 and NCo 376, two widely grown cultivars were infected. Ratings for the individual clones will be posted on the webcite: http://www.ars-grin.gov/ars/SoAtlantic /Miami/ngr/gallry01.htm. The low SCYLV infection found in the S. spontaneum clones suggests this group is the most resistant. The high susceptibility to SCYLV of the hybrid clones is consistent because a number of clones in their early pedigrees were susceptible.