Abstract: Lower concentrations of 2,4-D (0. 2, 0. 4, 0. 8 mg/L) were used as auxins for induced calli of rice (Oryza sativa L.) on induction media. The results showed that 0.8 mg/L concentration of 2,4-D could induce a large number of calli earlier from scutellum or other parts, but calli could not differentiate green buds. On the contrary, 0.2 mg/L concentration of 2,4-D could only produce a few white, smoother and more compact granular structures or calli under the base of coleoptile, and the formation of them was very late, but the calli could change into clustered-buds and produce fine roots. These clustered-buds were cut into small pieces and transferred into the regeneration media containing KT, a large number of normal green plantlets (reached over 80%) were produced from the clustered-buds and the plantlets were transplanted on the field, they grew well and produced normal seeds.

Key words: dichlorophenoxyacetic acid, one-step induction method of test-tube seedlings, organ culture

摘要： 以较低浓度(0.2、0.4、0.8 mg/L)的2,4-D作为水稻(Oryza sativa L.)的外植体(种子)诱导愈伤组织培养基中的生长素类激素，发现0.8 mg/L的2,4-D能较早地使胚的盾片产生大量的愈伤组织，但这些愈伤组织在原培养基上不能分化出绿芽。含0.2 mg/L的2,4-D能在胚芽鞘节等部位产生一些较光滑、致密、白色颗粒状的结构或愈伤组织，虽然它们出现较迟，但这些结构物能在原诱导培养基上逐渐转化成芽簇，并产生一些纤细的根。将芽簇分割成小块，转移到加有KT等的成苗培养基上，能形成大量的幼苗，绿苗频率达80%以上，明显高于一般报道的水平。试管苗经大田种植后生长整齐一致，能产生出正常的种子。

关键词: 组织培养, 2, 4-D, 一次成苗