【目的】通过对遗传转化过程中水稻愈伤组织本身的3种内源激素含量变化动态研究,探讨水稻愈伤组织生长发育过程中内源激素变化规律和激素间的相互关系,旨在为水稻遗传转化体系中合理使用植物生长物质提供参考依据。【方法】以广粳1号、特青、V20B为遗传转化供试材料,采用高效液相色谱法(HPLC)测定了遗传转化过程中4个主要时期愈伤组织中的内源脱落酸(ABA)、生长素(IAA)和玉米素核苷(Z)的含量。【结果】IAA主要存在于种胚诱导出的愈伤组织上及芽中,且过高的IAA含量不利于愈伤组织的诱导和生长;Z主要存在于种胚中,对愈伤组织诱导的启动有决定性作用,如果外植体中的Z含量太低,即使有较高的IAA含量也不能诱导出愈伤组织;过高的ABA对愈伤组织的诱导不利,但在继代培养时适量升高ABA含量有利于胚性愈伤组织的形成。【结论】内源激素对愈伤组织的生理状态有着极其重要的影响,其种类、含量及协调平衡是水稻愈伤组织形成和分化的关键。同时,诱导培养基中2,4-二氯苯氧乙酸(2,4-D)的浓度与水稻愈伤组织培养物中的培养力(愈伤组织质量,芽长和诱导率)有一定的相关性,且在培养基中加入2,4-D等生长调节剂类物质会对愈伤中的内源激素含量有一定的影响。
[Objective] In order to provide some reference frames for rational utilization of phytohormones or plant growth regulators in tissue culture, the dynamic changes of endogenous phytohormones in rice calli from four main processes of genetic transformation were studied. [Method] Using Guangjing No. 1,Teqing and V20B as materials,endogenous ABA,IAA and Z in rice calli in four main stages of genetic transformation were analyzed by HPLC. [Result] IAA was found to be more abundant in the callus buds than in the mature embryos. High content of IAA reduced callus induction and growth. Z was found to be mainly existed in seed embroys, being crucial for callus induction. Calli could not be induced when Z content was too low, even the IAA levels were relatively high. High content of ABA was negative to callus induction,but might increase embryogenic callus in the process of callus regeneration. [Conclusion] The kinds, contents and harmonious balance of endogenous phytohormones are key factors to callus induction and differentiation for rice. The concentration of 2,4-D could influence the culture's strength of callus and the levels of endogenous phytohormones.