摘要
大豆组织培养过程中一直存在着再生芽不生根、生根少、根系易污染以及再生植株移栽成活率低、生长不良等问题,严重制约大豆遗传转化效率的提升.本研究针对以上问题,以只有子叶、下胚轴和根系的"子叶植株"为砧木,以组织培养产生的再生芽为接穗,建立了一种简单高效的大豆再生芽嫁接快繁技术体系.实验结果表明,以出苗后4～6 d的大豆子叶植株为砧木,以不生根、生根少或根系污染的再生芽为接穗,构建嫁接复合体,再生芽的成活率达到79.8%±4.9%.此外,将再生芽分成2～3个茎段,分别做接穗创制以子叶植株为砧木的嫁接植株,其繁殖种子总数(234.5±39.1粒)较通过组织培养系统得到的单个植株(83.7±13.2粒)提高1.8倍.综上,本研究提出的以子叶植株为砧木、再生芽为接穗的嫁接方法省去了再生芽生根过程,能够有效解决大豆组织培养过程中再生芽不生根、生根少和根系易污染等问题,提高再生芽的成活率,缩短再生芽的繁殖周期,扩大再生芽的种子产量,进而显著提高再生芽的繁殖系数.该技术对提高大豆遗传转化效率,实现再生植株的工程化快繁具有重要意义,对解决其它双子叶植物组织培养过程中再生芽生根困难问题、提高遗传转化效率也具有借鉴价值.
Abstract
There are some root-related problems including difficult rooting and inadequate rooting of regener-ated shoots,microbial contamination of regenerated roots,low survival rate and poor growth of transplanted plants in the soybean tissue culture process,which significantly limit the efficiency improvement of genetic transformation.In this study,we established a simple and efficient propagation method for soybean regenerated shoot using a grafting system with cotyledon-only plant(COP)as stock.The results showed that the survival rate of the regenerated shoot in the grafting union with 4-6 d old COP as stock and the regenerated shoot with no root,few roots or microbially contaminated root as scion was as high as 79.8%±4.9%.After cutting a regenerated shoot into 2-3 stem segments and then grafting them with COP stock,the grafted shoots totally produced 1.8-fold more seeds(234.5±39.1)than that of an individual plant(83.7±13.2)derived from rooting induction in the tissue culture system.In conclusion,the grafting method using COP as stock and regenerated shoot as scion omits the root induction of the regenerated shoot in the tissue culture system;and resolves the problems of no rooting,few rooting and microbial contamination of roots in soybean tissue culture,improves the survival rate,and increases the seed number of the regenerated plants.Hence,the propagation efficiency was obviously elevated.This technology facilitates the efficient genetic transformation and engineered propagation in soybean and provides new insight into other dicots with problems in the rooting process of regenerated shoot in the tissue culture.
基金项目
农业农村部财政部现代农业产业技术体系建设专项(CARS-04)
中国农业科学院农业科技创新工程()
维普
万方数据