影响大白菜离体再生及基因转化的因素研究

以耐热大白菜42 号自交不亲和系的子叶为外植体,研究了几种因素对大白菜植株再生的影响和农杆菌介导法转CpTI基因的条件。含0.1 m g/LNAA, 1.0～2.0 m g/LCPPU, 5.0～10.0 m g/LAgNO3 的MS培养基较适合于大白菜42 号自交不亲和系的子叶离体培养再生植株。测定了在含不同激素组合的培养基上离体培养7 d 后的子叶的内源激素含量,在不定芽诱导培养基上子叶内源IAA、ABA 含量分别比培养在不含激素的培养基上下降42.6% 、10.5% , 比培养在生根培养基上下降52.4% 、19.0% ; iPAs 含量、GA1 3 含量分别比培养在不含激素的培养基上上升510.9% 、143.9% ,比培养在生根培养基上上升860.5% 、558.3% 。头孢霉素抑制子叶再生不定芽,而羧苄青霉素则有促进作用。筛选转化体的适宜卡那霉素浓度为5～10 m g/L。

FACTORS ON SHOOT REGENERATION AND GENE TRANSFORMATION OF CHINESE CABBAGE (BRASSICA PEKINENSIS)

Factors on shoot regeneration and gene transformation of Chinese cabbage (Brassica pekinensis) were investigated. The modified MS medium with 0.1 mg/L NAA, 1.0~2.0 mg/L CPPU, 5.0~10.0 mg/L AgNO 3 was useful to shoot regeneration from cotyledons of Brassica pekinensis . Endogenous hormone content of cotyledons, which were cultured on media with different hormone combinations for 7 days, was assayed. Level of IAA in cotyledons on the shoot induction medium was reduced by 42.6% and 52.4% respectively as compared with those in cotyledons on the hormone free medium and the root induction medium. Level of ABA in cotyledons on the shoot induction medium was decreased by 10.5% and 19.0% respectively. Level of iPAs was increased by 510.9% and 860.5% respectively, level of GA 1 3 was increased by 143.1% and 558.3% respectively. Carbenicillin could increase the rate of shoot regeneration from cotyledons of Chinese cabbage, while cefotaxime reduced the percent of shoot regeneration. The suitable concentration of kanamycin to selecting the transformed shoots is 5~10 mg/L.