Genetic transformation and various biotechnological treatments on hairy roots

本研究以发根农杆菌（Agrobacterium rhizogenes）转化几种园艺植物，获得的毛状根作为遗传转化和生物技术研究的目标。主要研究结果如下：1.以发根农杆菌（Agrobacterium rhizogenes）野生型菌株感染匍匐花、刺果花、空心菜、金鱼草和葡萄的叶片切段获得毛状根，建立了植株再生体系.用携带GUS和NPT II基因的根癌农杆菌感染猪毛菜根尖。筛选表达GUS活性和卡那霉素抗性的毛状根，并从这些毛状根中获得转基因植株.根尖分生组织经不同处理后，有丝分裂同步化率最高（30%），其中以磷酸盐饥饿、羟基脲和秋水仙素处理的组合最高.从同步化根尖细胞中分离染色体的试验由于染色体在分离过程中断裂，染色体纯化困难而失败.通过调整秋水仙素处理的时间和浓度，成功地从毛状根培养物中再生出四倍体植株.这些结果表明，包括毛状根在内的根培养物是遗传转化和其他生物技术处理的有用材料。

In this study, transformation of several horticultural plants with Agrobacterium rhizogenes was tried and the hairy roots thus obtained were used as the targets for the studies on the genetic transformation and various biotechnological studies. The results obtaiend are as follows :1. Plant regeneration systems have been established from the hairy roots obtained by infection of leaf segments with wild-type strains of Agrobacterium rhizogenes in Nierembergia repens, N.acoparia, Ipomoea trichocarpa, snapdragon and grape vine.2. Root tips of N.scoparia were infected with A.tumefaciens harboring GUS and NPT II genes. Hairy roots expressing GUS activity and resistance to kanamycin were selected and transgenic plants were regenerated from these hairy roots.3. Root tip meristems were subjected with various treatments for mitotic synchronization and the highest mitotic index (30%) was obtained with the combination of 3 treatments including phosphate starvation, hydroxyurea and colchicine treatments.4. Trials for isolating chromosomes from the synchronized root tip cells resulted in failure due to the break down of the chromosomos during the isolation process and difficulty in purification of the chromosomes.5. Tetraploid plants were successfully regenerated from the hairy root cultures after the treatment with colchicine by adjusting the proper time and concentration.6. These results indicate that root cultures including hairy roots are useful materials for genetic transformation and other biotechnological treatments.