Performance of exotic x indigenous crosses for combining ability over environments in opium poppy (Papaver somniferum L.). IV. capsule size and capsule number

Combining ability worked out from 5 x 10 (line x tester) data revealed that nonadditive gene action was more important than additive gene action for capsule numberand capsule size. Year effects were pronounced for both characters. Magnitude of variance for gca X year interaction was much less than the corresponding magnitude of sca x year interaction for capsule number. For capsule size, sca x year interaction variance was of less magnitude than the gca x year interaction variance. Crosses EC 11552 x KP and EC 11571 x Hariana for capsule number, and EC 11540 x DCG and EC 11556 x KD for capsule size were the best specific combinations. Single plant selection after inter-se mating in segregating generations would be the best way to improve these traits. Pedigree method would be a better approach in the cross EC 11548 x DCG for capsule size where additive gene effects were more important.