Effects of 2,4-D on the embryogenesis rate of wheat haploid induced by maize pollen

The distant hybridization was conducted between male sterile line and normal material with the inducement of four maize cultivars(Middle sweet,Super sweet,Black glutinous,Jiazhouhong).The results showed that high embryogenesis rates were obtained under the treatments of 75 mg/L to 200mg/L 2,4-D,the embryogenesis rate was the highest(5.88 %) under the treatment of 150 mg/L 2,4-D.A lot of haploids were gained when they were immersed in 150 mg/L 2,4-D after pollination for 5 d to 6 d,the frequency of the haploids immersed in 2,4-D 1 d after pollination was highest(5.38 %).The embryogenesis rate differed with different types of maize pollination,the order was as follows,sweet maize(2.99 %)glutinous maize(2.27 %)normal maize(2.08 %).The embryogenesis rate of wheat with double pollination(2.26 %)was higher than that of the single pollination(0.81 %).