Inheritance and Association of Six Traits in Safflower1

Abstract

The parents, F1 and F2 from four crosses of safflower (Carthamus tinctorius L. and C. palaestinus Eig.) were studied in field experiments. Data were taken on individual plants to estimate heritability, gene action, and mode of inheritance of plant height, time of flowering (TF), time to maturity (TM), time from flowering to maturity (TFM), leaf length, and stem diameter. In all crosses, F2 variability was largely genetic for all traits. Gene action was additive for plant height and leaf length, but nonadditive for TF, TM, and TFM. Gene action for stem diameter was additive in Cross 3 but nonadditive in Cross 4. The broad‐sense heritability estimates were high for all traits studied. Maternal effects were absent, except for TM and leaf length. In all F2's, continuous distributions were observed, suggesting multiple‐factor inheritance for plant height, TF, TM, TFM, leaf length, and stem diameter. Heritability estimates in the narrow sense for TF and plant height, calculated from the cross N4051 ✕ 830293, were 11 and 79%, respectively. In the same cross, the values for expected genetic advance for TF and plant height were 0.70 and 17.0%, respectively. On the basis of apparent gene action, heritability estimates and expected genetic advance, direct selection to improve plant height should be effective.Plant height was not associated with striped hull or flower color; however, plant height was associated with anthocyanin pigmentation. Also, TF was not associated with striped hull, anthocyanin pigmentation, or flower color. Correlation coefficients of TF with TM and TM with TFM were high.