The process in which the chromatin structure of the rDNA repeats is compacted. In S. cerevisiae, condensation and resolution of the rDNA occurs during anaphase. [ http://www.ncbi.nlm.nih.gov/pubmed/15137940 GOC:dgf http://www.ncbi.nlm.nih.gov/pubmed/10811823 ]
Synonyms: rDNA packaging rDNA condensation