利用自交不亲和系ＷＢ７和黑２２７配制成耐热早熟大白菜一代杂交新品种“津白４５”，生育期４５～５０天，株高３６ｃｍ，开展度４０ｃｍ，中桩类型，叶球近似筒形，球形指数２．１左右，外叶绿色，中肋白色，具有良好的商品品质和食用品质。３年品比试验每６６６．７ｍ２产量达３７８０．０～５２７４．２ｋｇ，比对照品种“夏阳５０”增产２５．０％～５２．２％，对霜霉病和软腐病的抗性极显著高于对照品种 The selfing incompatible WB7 and black 227 were used to prepare a new hybrid variety “Jinbai 45” with a new generation of heat-resistant and early-maturity Chinese cabbage. The growth period was 45 ~ 50 days, the plant height was 36cm, the development degree was 40cm, Cylindrical, spherical index of 2.1 or so, the outer leaves green, rib white, with good product quality and food quality. The yield of 666.7m2 in 3 years was 3780.0 ~ 5274.2kg per 666.7m2, which increased by 25.0% ~ 52.2% than that of “Xiayang 50”. The resistance to downy mildew and soft rot was significant Higher than the control varieties