We report here the generation of an additional collection of Dissociation (Ds) transposon-tagged, sequence-indexed lines of Arabidopsis thaliana. Our RIKEN Ds insertion collection now totals 17,668 lines. Our collection has preferential insertions in chromosomes 1 and 5, because Ds was transposed from start loci on those chromosomes (11,854 and 5,814 lines, respectively). We describe here features of the latter 5,814 lines. The former 11,854 lines have been described previously. We have created a searchable database of the insertion sites and mutated genes (http://rarge.gsc.riken.jp/), and are depositing these lines in the RIKEN BioResource Center (http://www.brc.riken.go.jp/lab/epd/Eng/). Our collection of these mutants will contribute to progress in functional genomics of plants.