2 MEDIUM CHAIN FATTY-ACID MUTANTS OF CUPHEA-VISCOSISSIMA

Cuphea viscosissima Jacq. is an herbaceous annual dicot indigenous to the U.S. This species is being developed as a new oilseed crop and commercial source of medium-chain fatty acids (MCFAs). In this paper, the phenotypes and genetics of the mcm-1 and cpy-1 mutations of C. viscosissima are described. These mutations affect the percentages of fatty acids of seed storage lipids. They were induced by treating seeds with 0.04 M ethyl methanesulfonate for 5 h. Observed segregation ratios for these mutations were not significantly different from expected ratios for codominant genes. The mcm-1 mutation eliminates 95.0 % of wildtype MCFAs - caproic (C6:0), caprylic (C8:0), and capric (C10:0) acid percentages are decreased from 0.8 to 0.0 %, 20.7 to 0.5 %, and 68.6 to 6.7 %, respectively. The cpy-1 mutation decreases C6:0 and C8:0 from 0.9 to 0.0 % and 19.8 to 3.9 %, respectively, whereas it increases C12:0 and C14:0 from 2.2. to 14.3 % and 0.8 to 7.4 %, respectively.