Genetics of morphine, yield and its candidate characters in opium poppy (Papaver somniferum L.)

Combining ability in opium poppy, Papaver somniferum L. was analyzed through full diallel cross comprising five parents, 20 F1s (including reciprocals) and 20 F2s (including reciprocals). The analysis of variance revealed significant differences for all the characters demonstrating considerable variation among genotypes. Estimates of components of general and specific combining ability variances exhibited equal importance of both additive and non additive gene actions for the expression of all the characters. However, higher magnitude of SCA components of variance indicated preponderance of non –additive effects for all the traits except for leaves/plant, seed yield and opium yield in F2 generation. The average degree of dominance was more than unity, showed over dominance and also conferred above findings. Among the parents NB-1KR401-3/3 for capsules/plant, stem diameter, capsule wt/plant, capsule size, peduncle length and seed yield, NB-5KR3-2-2/1 for days to 50% flowering, plant height leaves/plant, capsule wt/plant, and seed yield, Papline and 58/1 for plant height and opium yield and NB-5KR40-7/2/-3 for morphine content were found good general combiners. Inclusion of lines with good GCA in a single or multiple crosses followed by intermating i.e. population improvement approaches may be expected to offer genetic improvement in breeding for higher opium, seed yield and its component traits.