SONG Ju-hong1， YUE Cun-qi1， ZHANG Guo-cong1*， ZHANG Chao2
（1Shijiazhuang Academy of Agricultural and Forestry Sciences，Shijiazhuang 050041， Hebei，China；2Guoyan Seed Co.Ltd of Hebei Province，Baoding 072650，Hebei，China）
Abstract：‘Hualyu No.4’ is a high quality pakchoi F1 hybrid developed by crossing W-1-8-1 as female parent and S-1-2-9 as male parent. The plant is rather erect， 21 cm in height and 29 cm in width. Its leaf is flat and dark green in color. The petiole is green and 5.3 cm in width，1.4 cm in thickness. The single plant weight is 260 g. It has crisp quality and tastes rich with less fiber. It can yield over 42 t ·hm-2 in summer and autumn cultivation. Its resistances to virus disease， downy mildew and soft rot are stronger than that of the check‘ Jingguan No.1’ . It has good tolerance to heat. It is suitable for summer and autumn cultivation in northern China.
