Abstract

                                To study the nature and magnitude of gene effects in the present investigationfor yield and its components in Safflower (Carthamus tinctorius L.),Generation mean analysis with three-parameter model with χ2 test indicatedthat additive-dominance model was inadequate for all the traits in all thecrosses used to estimate the gene effects. Duplicate type epistasis playedgreater role than complementary epistasis. On the basis of six parametermodel, main effect viz., m, d and h and all three digenic interactions viz.,(i), (j) and (l) were significant for DF, DM, PH, NBPP, NCPP and SYPP in crossGMU-2720 x GMU-3423; for DM, PH, NSPC, SYPP and HC in cross in crossJMU-1339 x GMU-3423 indicated that involvement of d, h and epistasisinteraction for controlling this trait. For DF, DM, PH, NBPP, NCPP, TW and HCin cross-1; for DF, DM, PH, NBPP, NSPC, TW, SYPP and OC in cross-2 for thesecharacters indicating the duplicate type of interactions. For NSPC and SYPPin cross-1; for NCPP and HC in cross-2;for these characters indicating thecomplementary type of interactions. This suggested that duplicated type ofgene action was present confirming the importance of dominance effects.The study revealed the importance of both additive and non-dominancetypes of gene action for all the traits studied. Thus, considerable non-additivegenetic effects observed in this study suggest that selection in an advancedgeneration will be appropriate,

Key words : Safflower, Quantitative trait, Joint scaling test, Gene effects, Generation mean analysis