Genetics of Morphine and Seed-Related Traits in Opium Poppy

Abstract

ABSTRACT Combining ability in opium poppy, Papaver somniferum L. was analyzed using a line × tester (L × T) design. A total of 15 diverse, inbred lines of opium poppy and three testers were selected on the basis of seed and straw yields and hybridized in L × T fashion to produce an F1 generation (4 & 5). The mean sum of squares due to lines, testers and lines × testers were significant for all the characteristics studied, suggesting the experimental material possessed considerable genetic variability. Estimates of general and specific combining ability variances for all of the characteristics were also significant, indicating both additive and nonadditive gene action in inheritance of these characteristics. The larger magnitude of specific combining ability (SCA) mean sum of squares suggested that the nonadditive gene action was predominant for capsules per plant, straw and seed yields per plant, and morphine content in straw. Conversely, the seed oil and seed protein content were governed by additive gene action. None of the inbred lines were observed to be good general combiners for all the studied traits. Among females, the economic parent Shubhra showed good general combining ability (GCA) for all traits. Interestingly, Shubhra was a parent in any of the crosses that showed high SCA, except for the characteristics of morphine content and seed oil content. Considerable amounts of economic heterosis were recorded for all of the traits, except for seed protein content and the morphine content of straw.