Analysis of variance of partial diallel tables

The theory of variance analysis of partial diallel tables, following Hayman 's proposal of 1954, is presented. As several statistical tests yield simil ar inferences, the present analysis mainly proposes to assess genetic varia bility in two groups of parents and to study specific, varietal and mean he teroses. Testing the nullity of specific heteroses equals testing absence o f dominance. Testing equality of varietal heteroses of the parents of a gro up is equivalent to testing the hypothesis that in the other group allelic genes have the same frequency. Rejection of the hypothesis that the mean he terosis is null indicates dominance. The information obtained complements t hat provided by diallel analysis involving parents and their F-1 hybrids or F-2 generations. An example with the common bean is included.