Seeds can reach maturity and have a high oil content, but if they're green, their price drops. Seed crushers remove the green from the oil with bleaching clays, which produce an added expense and pose an environmental problem. Canola is an oilseed crop grown mainly in parts of western Canada, with some acreage in Ontario and the Pacific Northwest, north-central, and southeastern United States. Its yellow flowers produce pea-shaped pods that contain tiny seeds harvested for their oil. Canola oil contains omega 3 fatty acids, acclaimed for improving human immune and vascular systems.
Many plants break down chlorophyll even after a freeze.
That's what happens in the fall when chlorophyll disappears and other leaf pigments become visible, creating spectacular fall foliage. Whitmarsh works collaboratively with Donald R. Ort, head of the ARS Photosynthesis Research Unit. Their goal is to identify Arabidopsis mutants that develop little or no seed chlorophyll, as well as other mutants that display early chlorophyll breakdown during seed maturation. To check seed degreening, postdoctoral research scientist Adriana Ortiz-Lopez puts plants in a growth chamber with freezing air blowing over them. She also keeps watch over other plants maintained at above-freezing temperatures.