Abstract: Sugarcane yellow leaf disease caused by Sugarcane yellow leaf virus (SCYLV) was found in several sugarcane growing area in South China. Field investigation revealed that both Succharum officinarum for fruit and S. hybrid for sugar production were infected. The cultivars show yellow leaf symptom included Badila (Red Stalk and Yellow Stalk), ROC16、ROC22、ROC25、YT93-159、127Q、Q174、YT8388 and HOCP91-555. The percentage of diseased plant was 0.5-10% in most fields with the highest figure of 80% occasionally. Sequencing of viral CP coding region (591bp) amplified by RT-PCR showed 100% nucleotide identity between most SCYLV isolates collected from South China and SCYLV B1 strain isolated from Brazil (with a few exception bearing 1-3 nucleotides difference). Ceratovacuna lanigera, the predominant aphids species on sugarcane in South China was verified as a new vector for SCYLV. A nested-RT-PCR technique was established for SCYLV detection from individual viruliferous aphids and plants in early stage of infection. About 80% adult aphids feeding on sugarcane plants with yellow leaf symptom for over 2 weeks showed SCYLV positive by this technique. In addition to the capacity of transmission SCYLV between sugarcane plants efficiently, Ceratovacuna lanigera could transmit SCYLV to sorghum, rice and maize seedlings with efficiency of 100%(9/9),75%(6/8) and 50%（4/8）respectively while 15 viruliferous aphids were inoculated for each plant. SCYLV was not transmitted to wheat and banana by Ceratovacuna lanigera in this study.

Key words: Sugarcane yellow leaf virus, Ceratovacuna lanigera, vector