Abstract: The experimental results indicated that the mature rice seed is a competitive explant. Since the reaction of ABA on scutellum is not sensitive and higher level of ABA can inhibit the plumule and radicle, so that it promotes the scutellum callus growth. The callus were compact, white and very uniform. The adjustment of medium concentration enhanced effectively the frequency of plant regeneration and reduced the frequency of the dead callus. Higher level of 2,4-D (> 1 mg/l) and BA (1 mg/l) are harmful to callus formation and regeneration in mature seed culture of indica rice. The reaction of indica rice variety on 2,4-D, BA was more sensitive than japonica rice variety. Adding 2,4-D 0.5 mg/l, BA 0.5 mg/l and ABA 5 mg/l to MS inducing medium for mature seed culture is suitable.

Key words: tissue culture, scutellum, competitive explant, abscisic acid

摘要： 实验结果认为，水稻成熟胚是一种“竞争性”外植体。高浓度的脱落酸（ABA）能有效地抑制胚芽和胚根的生长，而对水稻盾片愈伤组织的生长影响较小，从而促进盾片愈伤组织的同步健壮生长。这些愈伤组织致密，呈乳白色且分化频率高。调节分化培养基的浓度可减少愈伤组织变褐老化，有效地提高愈伤组织绿苗分化率。在诱导培养期间，较高的2，4－D浓度（大于1 mg/L）和6－BA会抑制种胚体细胞愈伤组织的诱导，其中籼稻比粳稻敏感。在诱导培养基中附加2，4－D 0.5 mg/L，BA 0.5 mg/L，ABA 5 mg/L，B_1 (5－10 mg/L)对成熟籼稻种胚培养是较合适的。

关键词: 组织培养, 盾片, 竞争性外植体, 脱落酸