Seawater is considered as an economic and eco-friendly alternative for chemical fertilizer because it contains various plant essential minerals required for plant growth. Seawater application can have various effects on crops physiologically and transcriptionally. To examine transcriptional changes of crop in response to deep seawater (DSW), RNA sequencing was carried for Ligularia stenocephala, a vegetable crop known as “Gondalbi”, treated with 5% and 10% of DSW (designated to DSW5 and DSW10), or 500X and 1000X of a fertilizer (designated to SWF500 and SWF1000) made of filtered DSW and additional minerals. RNA sequencing generated 152 million clean sequence reads in total, of which de novo assembly resulted in 147,406 unigenes with an average length of 566.6 bp. The GC content of five transcriptomes ranged from 42.95% to 43.65% and N50 was 776 bp. Annotation of all identified unigenes were performed using seven different databases, from which 67,592 unigenes (45.8%) was annotated. KEGG annotated a total of 7,009 unigenes (22.9%) into 421 pathways. As L. stenocephala is known for its anti-oxidative properties, we examine the genes associated with the biosynthesis of natural antioxidants and several unigenes involved in the biosynthesis of glutathione, tocopherol, beta-carotenoids, flavonoids, and ascorbic acid were identified in this study. We carried out the mining of SSRs and identified 35,280 simple sequence repeats from the L. stenocpehala transcriptome. Present data would be valuable for understanding transcriptional properties following seawater application in other crops and for the investigation of the functional properties and the therapeutic capabilities of L. stencoephala.

Keywords: Gondalbi, RNA Sequencing, Differentially expressed genes, Rocket, Antioxidant