The complete mitochondrial genome sequence and phylogenetic analysis of sugarcane (Saccharum spp.) cultivar ROC22.

The complete mitogenome of Saccharum spp. hybrid ROC22 (a modern sugarcane cultivar) was sequenced and analyzed in the present study. Our results revealed that, unlike most plants, the complete mitogenome of sugarcane contains two distinct circular chromosomes, Chromosome 1 and Chromosome 2. The length of Chromosome 1 is 300,837 bp with the GC content of 43.93%, and the length of Chromosome 2 is 144,755 bp with the GC content of 43.57%. Apart from 16 tRNAs and six rRNAs non-coding genes, there are 20 protein-coding genes in Chromosome 1, including six nad genes, four rps genes, three atp genes, three ccm genes, two cox genes, one mat gene and one mtt gene. Chromosome 2 contains 18 genes, including five tRNA genes and 13 protein-coding genes (four nad genes, three rps genes, two atp genes, one ccm gene, one cob gene, one cox gene and one rpl gene). Phylogenetic analysis indicated that Saccharum spp. hybrid ROC22 is close with Saccharum officinarum Khon Kaen 3 and Sorghum bicolor species. [ABSTRACT FROM AUTHOR]