Heterosis and segregation on agronomic and yield traits in Brassica napus L.

Two cytoplasmic male sterile maintainers(pure line from different background) as female parent were crossed with one restorer to produce two F2 segregating populations and one F2∶3 families population.The heterosis of F1 for two populations were analysed.Results indicated that seed yield/plant,total number of siliques per plant,total number siliques of first branches per plant had significant positive heterosis.Heterosis for 3 yield components from field showed that seed yield/plant of F1 hybrids had highest positive mid-parent heterosis.The heterosis for seeds/silique and 1000-seed weight was low.Heterosis for 3 yield components was total number of siliques per plant1000-seed weightseeds/silique.The heterosis of seed yield per plant,seed yield per pot,total silique number in first branch in F2segregating population and F2∶3family populations decreased significantly than that in F1generation.There was a great segregation in F2and F2∶3families populations.Superior heterosis was found out in segregating populations.