The Canadian prairies have vast acreages of saline land, which is unsuitable or uneconomical for food crop production. These lands may be suited to growing industrial crops, if varieties with stress tolerance and low inputs can be selected. Ethiopian mustard (Brassica carinata), is a new biorefinery seed crop under development in Saskatoon. If.B. carinata could be grown successfully on large acreages of marginal land, farmers may have two biofuel opportunities, first to harvest mustard seed for biodiesel and second to contribute mustard residue into stores of biomass feedstock for cellulosic ethanol.

To explore the potential of growing B. carinata crops on prairie saline land and to determine mechanisms of tolerance to salinity, we conducted a 72 day greenhouse pot study comparing two genetically-related lines (yellow-seeded and brown-seeded) growing in soil amended at day 15 with 50 mM and 100 mM sodium sulphate. By 42 days, growth was compromised more severely in the yellow-seeded line than in the brown-seeded line at 100 mM, even though the yellow-seeded line was smaller than the brown-seeded line even without saIinity treatment. This salinity-dependent growth suppression was consistent with reduced growth of the yellow-seeded line in lithium chloride (in an earlier study reported in Li et al. 2009. Plant Sci. 177: 68-80). However, the mechanism of tolerance in the brown-seeded line appears to differ between sodium sulphate and lithium chloride. The presentation will include a comparison of growth of the two lines on sodium sulphate lines and will highlight differences between their metabolomes, chlorophyll degradation products, and their transcriptomes as measured by the Agilent Brassica napus 105K oligo array.