Sequencing and analysis of complete chloroplast genomes of einkorn wheats Triticum sinskajae and Triticum monococcum accession k-20970

Triticum sinskajae A. Filat. et Kurk. has been discovered in the early 1970s during the reproduction of Triticum monococcum L. accession k-20970. It is still debated whether it is a new species or a spontaneous mutant of T. monococcum. Although T. sinskajae appears to be genetically distinct from several T. monococcum lineages, there is still no data on the differences from accession k-20970, from which it may have originated. The purpose of this study was to compare the chloroplast genomes of T. sinskajae and T. monococcum accession k-20970 and clarify the phylogenetic relationships between einkorn wheats. Complete chloroplast genomes of T. sinskajae k-48993 (Dagestan), T. monococcum k-20970 (Turkey), T. boeoticum k-58674 (Armenia) have been sequenced and annotated for the first time. Chloroplast genome sequences of T. monococcum subsp. monococcum and T. urartu were used for comparative analysis. However T. monococcum k-20970 and T. sinskajae k-48993 had common mutations that were absent in T. monococcum subsp. monococcum, they also were polymorphic in 10 nucleotides, including 1 transversion, 1 deletion, 4 insertions and 4 bp inversion of AGAA to TTCT in the rbcL-psal intergenic region. Due to genetic and phenotypic differences T. sinskajae k-48993 and T. monococcum k-20970 can be considered different species. A comparison of the chloroplast genomes of einkorn wheats showed a common origin of the plastomes of three closely related species —T. sinskajae, T. monococcum and T. boeoticum, while T. urartu can be assigned to another clade.