In this study, 36 citrus species representative of the Citrus genus have been selected, their chloroplast genomes sequenced and compared. The selection comprises different Citrus species covering the three main documented groups (citrons, pummelos and tangerines) which are described as citrus found

Chloroplasts are organelles of prokaryotic origin within plant cells in which the photosynthetic machinery resides. Additionally to photosynthesis, chloroplasts carry out other important metabolic activities such as the production of, certain amino acids and lipids, vitamins, some of the colorful pigments in flowers, starch and several aspects of sulfur and nitrogen metabolism. As a remnant of their prokaryotic origin, chloroplasts have their own genome along with the corresponding transcriptional and translation machinery to express their genetic information. The organization of the chloroplast genome is quite conserved and it is highly similar to the inferred ancestral angiosperm chloroplast genome. Therefore, C sinensis chloroplast genome can be considered a good model for the study of citric chloroplast genomes.