Relative Efficinency of Several Selection Indexes as Estimation of Introduced Genotypes of Rapseed Brassica napus L.

Abstract

Twenty seven genotypes of introduced Rapeseed were grown in November ,2008 at Kirkuk govermentery , using randomized complete block design with three replicates for evaluation through coustructing several selection indexes and calculation of the gains expected in the seed yield . The analysis of variance results for studied characters (seed yield , period to 50% flowering , plant height , number of primary branches , number of pod/plant , number of seed /pod and 1000 seed weight ) . showed that mean square of genotypes were highly significant for all characters . Seed yield had significant positive phenotype and genetic correlation with number of pods , number of branches and plant height .Heighly phenotypic and genetic variation coefficient for seed , numer of pod and 1000 seed weight , but highly environmental variation coefficient for number of branches . This inverse on the value of broad sense heritability estimates ranged from (0.278) for number of branches and (0.969) for duration to 50% flowering , high genetic advance was showed for seed yield and number of pods 59.85% and 56.06% respectively . The selection index constructed from number of branches and number of seed /pods had the highest increase in the efficieny (98.528%) as compand with direct selection for yield . Using this index for genotypes evaluation revealed that the higher mean of selection index was (19.717) for genotypes RPGP902 followed by genotypes Cocktail and RPGP 909 had index value (19.536 and 19.352%) respectively.