AbstractChicory yellow mottle virus, ringspot strain (CYMV‐RS), supports the replication of a low molecular weight RNA (0.17 × 106daltons) associated with CYMV‐T (type stain).Competition hybridization experiments revealed lack or nucleotide sequence homology between 0.17 × 106mol. wt. RNA (Sat RNA) and CYMV‐RS genomic RNAs, and partial homology (33 %) with CYMV‐T genomic RNAs. However, such apparent partial homology can be due to contamination of CYMV‐T genomic RNAs with a multimeric form of Sat RNA having a similar molecular weight. On this account the hypothesis that CYMV‐T Sat RNA is a true satellite RNA be