De-novo draft genome sequence of Crocus Sativus L, Saffron, a golden condiment

Crocus sativus L, saffron is the highest priced but low yielding plant of medicinal and culinary importance. Despite its economic status, the omic information on this plant is very scarce, with only a couple of transcriptomics and epigenetic studies. In the present study, the draft genome sequence of C. sativus has been assembled using Illumina sequencing. In fact, this is the first genome sequence from any member of family Iridaceae . Genome size of C. sativus was estimated to be 3.5 Gb and the draft genome is 3.01 Gb long with 84.24% genome coverage. In total, 8,62,275 repeats and 9,64,231 SSR markers have been identified. A total of 53,546 functional genes were annotated, out of which, 43,649 proteins were associated with GO annotation. 5726 proteins were identified as transcription factors, with MYB & MYB related family proteins being more abundant. Orthology analysis of C. sativus with 3 different monocot species of the same plant order and rice (model monocot plant) revealed 7328 proteins clusters to be conserved in all the five plant species, whereas 2510 proteins cluster were unique to C. sativus only. 10,912 unigenes of C. sativus were mapped to 387 KEGG pathways of monocot. The genes involved in the pathway of apocarotenoids biosynthesis (crocin, crocetin, picrocrocin, and safranal) were present in the draft genome.