Variation in Yield, Oil, and Fatty Acid Composition Among Niger Accessions.

In the United States, Niger (Guizotia abyssinica L.) is primarily marketed as a seed of choice for American Goldfinches (Carduelis tristis) as well as other song and ground feeding birds because of its high oil content. In countries such as Ethiopia and India, niger is grown as an edible oilseed crop. The objective of this study was to determine the variation that exists among the majority of the USDA niger germplasm collection for seed yield, seed oil and fatty acid composition. Fourteen niger plant introductions (PIs) of Indian, Ethiopian, and American origin were obtained from USDA/ARS germplasm collection at Pullman, WA. Ten replications of the fourteen PIs were planted under field and greenhouse conditions at the East Tennessee Research & Education Center in Knoxville in August of 2012 using a completely randomized design. The traits analyzed included plant height, flowers per plant, seed per flower, primary branches per plant, estimated seed per plant, seed oil and fatty acid composition. Seed oil and fatty acid composition were analyzed using Near Infrared Spectroscopy (NIRS). Results showed significant differences (P<.05) among the fourteen PIs for all traits. Estimated seed per plant ranged from 1,717 to 17,102 seeds (PI508073 and PI508079, respectively) and seed oil ranged from 32.87 to 37.89% (PI508076 and PI509436, respectively). Major fatty acids included stearic, palmitic, oleic, and linoleic; with linoleic acid in greatest amount. PI508079 had the best combination of seed yield, seed oil, and linoleic acid content. Crosses among five of these PIs will be further evaluated for genetic variation, thereby determining the feasibility of future breeding efforts to increase seed yield and oil composition. Research will be conducted at three TN locations in the summer of 2013 and 2014 on parents, F1’s, F2’s, and backcrosses.