RECURRENT MASS SELECTION FOR REDUCED SEED DORMANCY IN CUPHEA-LANCEOLATA AND CUPHEA-LAMINULIGERA

Seed dormancy is a domestication barrier in certain Cuphea species. Between and within species variation has been observed for seed dormancy in agronomically promising Cuphea species, e.g., C. laminuligera Koehne and C lanceolata Ait. In tins note, we report on progress made in reducing seed dormancy through recurrent mass selection in the C. lanceolata population LN43 and LN78. The germination percentages of unselected LA12 and LN43 populations increased from 0.0 % to greater than 95.0 % following an after‐ripening period of 20 weeks. We observed no germination percentage differences between unselected and selected LN43 populations following two cycles of selection. In contrast, there were highly significant differences between the unselected and selected populations of LA12 following two cycles of selection. The germination percentages of cycle zero (C0) and cycle two (C2) populations after‐ripened 10 weeks were 10.7 and 92.7 %, respectively. After one cycle of selection in the C. Lanceolata population LN78, the germination percentage of seed after‐ripened 10 weeks had increased from 1.3 % for the Co population to 28.7 % for the C0 population. In summary, mass selection greatly reduced seed dormancy in LA12 and LN78, but had no effect in LN43. Copyright © 1990, Wiley Blackwell. All rights reserved