Analysis of Heterosis of Seed Yield and Its Components of Inter-varietal Cross in Brassica napus L

Heterosis of seed yield and its components of 66 crosses,from a diallel cross design of 12 parental varieties of Brassica napus L.were studied.In seed yield per plant,21 crosses gave a significant heterosis,over better parent percentage (hb) was 7024%(3070%～21810%)in average 8 crosses gave over better parent heterosis (357%～2048%)in 1000seed weight,but 7 crosses of them were parents with lower 1000seed weight.47 crosses gave 2802%(093%～9787%)of hb for pods number per plant in averagehb of 13 crosses showed 1167% in average for number of seed per pod.Results demonstrated that there was a large potential heterosis in seed yield in B.napus L.The heterosis of pod number per plant made the biggest contribution to heterosis seed yield.The possible ways of the potential heterosis utillization were discussed in this paper.