The genetic control of pod dehiscence was studied through the production, field trial and subsequent
analysis of a full diallel involving seven parents selected for high and low resistance to pod shattering.
Additive gene effects were most significant among the measures of pod shattering resistance with only
minor contributions from non-additive gene effects. Genetic variation in measures of the stiffness of
the pod wall were, however, determined by dominant gene effects. Genes for increased pod shattering
resistance acted recessively. All characters showed high levels of heritability. Correlations among pod
shatter resistance characters and other pod, raceme and plant characters were low suggesting that
resistance is likely to be independent of other important agronomic traits.