Genetic inheritance of proportion of pod walls and other yield components in white lupin

The present study was conducted to investigate the genetic inheritance of pod components in spring-sown white lupin. An analysis of the genetic parameters of proportion of pod walls and related pod components should be helpful to define a selection strategy in the future lupin breeding programs. Two mating designs were used, a complete diallel, and a half diallel, without reciprocals and without selfing. The parental lines covered the range of genetic variation for the proportion of the pod walls available in the white lupin collection from INRA, France. Diallel analyses were carried out via Griffing (model I and II) and Hayman methods. Proportion of pod walls, seed weight per pod and mean seed weight showed a mainly additive inheritance. Narrow sense heritability was higher for the proportion of pod walls than for the other pod components. The correlation between general combining ability (GCA) and parental phenotypic values was high for proportion of pod walls. This suggested that mean parental performance could be a useful indicator of mean cross performance for the proportion of pod walls in white lupin. For pure line breeding, the estimates of GCA values showed that Egyptian accessions would be valuable parents. Breeding for reduced proportion of pod walls may be a way of improving seed yield.