INCREASING ERUCIC-ACID CONTENT IN ETHIOPIAN MUSTARD THROUGH MUTATION BREEDING

Ethylmethane sulphonate (EMS) was applied to seeds of the Ethiopian mu stard (Brassica carinata A. Braun) line C-101. Bulk samples of M-3 see ds from 8331 M-2 plants were evaluated for the fatty acid composition of their oil by near-infrared reflectance spectroscopy (NIRS) and by f urther gas chromatography on selected samples. A putative mutant, N2-6 230, showing very low oleic acid content (4.7% vs. average of 8.6% in C-101) and erucic acid content within the range of variation of the li ne C-101 (40-49.3%) was identified. The M-3 progeny of this mutant sho wed a wide segregation for erucic acid content (39.1-57.9% vs. 41.8-50 .3% in C-101). and maintained levels of oleic acid lower than in line C-101. Selection for high erucic acid content in the M-3 and M-4 gener ations led to the fixation of this mutation in the M-5 generation (52. 2-59.3% vs. 39.0-47.6% in C-101). This is the first high erucic acid l ine obtained in Brassica species through mutation breeding. Its utilit y in future programmes to develop very high erucic acid lines is discu ssed.