Genetic variance of six agronomic characters in three lentil (Lens culinaris Medic) crosses

Abstract

Three lentil (Lens culinaris Medic) crosses (cross 1 = ‘Chilean’ × PI 297784; cross 2 = ‘Tekoa’ × PI 212611; cross 3 = ‘Precoz’ × PI 212611) were advanced in a hierarchal design from the F2 generation to the F5 generation and tested in replicated field experiments. The purpose was to estimate the genotypic variances and covariances for several characters and to partition these into components due to additive, dominance, and additive × additive variances. Additive genetic variance was the major component of variance in cross 2 for all characters, except plant height and seed weight. Unexpectedly, estimates of dominance variance appeared to be high in crosses 1 and 3. Estimates of the additive × additive component seemed very small in all three populations. The dominance variance component estimates were consistently high for plant height in the three crosses and for seed weight in crosses 2 and 3. Where parental means were close, additive variance estimates were often low and in many cases negative. The unexpected high ratio of dominance variance to additive variance indicated that dominance variance was important in the crosses we studied.