Abstract:

Regional trial for new cultivars is an essential part of crop breeding, and it might provide large amounts of information to breeder. According to the results of the national regional trail for winter type rapeseed in four groups, the upper, middle and Lower Yangtze River and Yellow and Huai River in the past twenty years, new varieties showed upward trend in average yield overall. The changes of average effective pods per plant were not distinct, but the number of seeds per pod and 1000-seed weight had moved up among the four groups. The increase of the number of seeds per pod in the 3 Yangtze River groups was higher than that in Yellow and Huai River group, while the increase of 1000-seed weight was just opposite. Resistances of new varieties to Sclerotinia sclerotiorum and viral disease had increased continuously in past twenty years. Genetic improvement for winter type rapeseed should be focus on seeds per pod and 1000-seed weight in the future, and seed yield of new varieties in all four groups is expected to increase.