Variation in fatty acid content and seed weight in some lauric acid richCuphea species

Abstract

Significant genetic variation for lauric acid (12∶0) and capric acid (10∶0) composition and seed weight was measured within lauric acid-rich, self-pollinating germplasm accessions ofCuphea wrightii, C. tolucana, andC. lutea. Means and ranges of individual plant progenies for 12∶0 content ofC. wrightii accessions was 60.5±.63% (49.8±65.8%), 10∶0 content was 23.7±.54% (18.6±33.0%), and 1000-seed weight was 1.50±.03 g (1.20–2.47 g). Progenies of single plant selections carried to the S₂ generation exhibited reduced variability within selections, but significant variation among selections for 12∶0, 10∶0 and 1000-seed weight. Variation among single plant selections ofC. tolucana was less than that ofC. wrightii and attributed to a restricted germplasm base. Means and ranges for 12∶0 content were 61.6±.47% (59.2–69.9%), 10∶0 was 22.3±.62% (11.7–25.3%), and 1000-seed weight was 1.40±.05 g (0.90–1.69 g).Cuphea lutea has a significantly different 12∶0−10∶0 profile than the other lauric acid-rich species. Means and ranges for 12∶0 were 36.8±.14% (33.7–40.8%), 10∶0 was 21.8±.08% (16.4–23.9%), 1000-seed weight was 2.26±.02 g (1.82–272 g). The 1000-seed weight was highly positively correlated with 8∶0, 10∶0, 18∶1 and 18∶2 contents and highly negatively correlated with 12∶0, 14∶0 and 16∶0 in bothC. wrightii andC. tolucana. No such relationship was found forC. lutea. A highly significant negative correlation was also measured for 12∶0 and 10∶0 contents inC. wrightii andC. tolucana.