INHERITANCE AND FATTY ACID COMPOSITION OF A YELLOW-EMBRYO MUTANT IN TURNIP RAPE (BRASSICA CAMPESTRIS L.)

The inheritance of a yellow-embryo mutant in Brassica campestris L. was shown to be determined by a simple recessive gene yy under embryonic control. Analysis of mature seed on heterozygous plants indicated that the content of each of the polyunsaturated fatty acids linoleic and linolenic, for the mutant seed, was approximately 3 percentage-points less than for the normal seed. The reduction of linolenic and linoleic acid to almost the same extent might indicate that the desaturation pathway from oleic acid, rather than the elongation pathway from dodecatrienoic acid, has been involved to effect these changes.

Amino acid, sugar, and organic acid content during germination of Gateway barley and its chlorophyll mutant

Amino acids and total soluble sugars in the embryo and endosperm of etiolated seedlings of Gateway barley and its mutant were compared over a 10-day period. The endosperm of the mutant had a lower reserve of protein but the levels of protein and free glycine, which is the nitrogenous precursor of chlorophyll, were similar in the embryos of both lines. Thus the low reserve of nitrogen in the mutant seed was not responsible for its virescent character. Based upon the changes in the amounts of endogenous amino acids it appeared that the free amino acids were direct precursors of protein. The content of total soluble sugars was similar in both lines. Shoots of light-grown seedlings of the mutant accumulated considerably more malate than those of the normal line. Although there was special interest in determining the amount of succinate at different stages of seedling development, none was detectable until the 10th day.