ESTs of Chenopodium quinoa from seed, salt-stressed, and non-stressed tissues
Chenopodium quinoa
Quinoa (Chenopodium quinoa Willd.) is a staple food crop for millions of impoverished subsistence farmers of Andean South America where it has been cultivated for millennia. Quinoa’s nutritional quality is exceptional. The seeds have an excellent balance of carbohydrates, lipids, and proteins for human nutrition.  Because of quinoa’s nutritional qualities, its natural adaptation to harsh conditions, and its cultural acceptability, increased quinoa production is the single most important prospect for addressing problems of food security in Andean South America.  Here we report the first large scale sequencing (454-pyrosequencing  and Sanger sequencing) and annotation of the quinoa transcriptome, including deep sequencing of eight development stages of the seed transcriptome, as well as the root, leaf and flower transcriptomes collected from plants grown under differing salinity concentrations.  De novo assembly of the reads resulted in 63,151 contig consensus sequences with an average read length of 530 bp.  Significant BLASTx alignments with the non-redundant protein database were identified 26,302 (42%) of the consensus contig sequences (=1e-15).  A total of 806 and 218 putative microsatellite and single nucleotide polymorphism (SNPs) loci were detected. The utility of the EST library was shown via targeted BLASTX searches for genes known to be involved in salinity stress tolerance and the biosynthetic pathway for saponin production, an antinutritional triterpenoid component found of the seed coat of bitter quinoa varieties.