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众所周知,变异是生物进化的基础。没有变异,进化就无从发生。导致生物变异出现的一个重要途径是遗传物质的重组。在植物界中,遗传重组主要是通过有性生殖来实现的。但在一些低等植物,如细菌、真菌和部分藻类中,“无性重组”仍占相当重要的地位,重组过程主要是借助于转化、传导、接合来实现的。低等植物进化为高等植物,在生殖方式上表现为有性生殖体制更加完善。因此,有性生殖在遗传重组中的地位就显得愈加重要了。高等植物的无性重组一般只能在人工条件下才能实现。这就是七十年代以来发展起来的体细胞融合、核转移、细胞器交换等细胞工程技术。
As we all know, mutation is the basis of biological evolution. Without variation, evolution can not happen. One of the important ways leading to the emergence of biological variation is the reorganization of genetic material. In plant kingdom, genetic recombination is mainly achieved through sexual reproduction. However, in some lower plants, such as bacteria, fungi and some algae, “asexual recombination” still occupies a very important position, the reorganization process is mainly achieved by means of transformation, conduction, bonding. Lower plants evolved into higher plants, the reproductive performance of sexual reproduction system is more perfect. Therefore, the status of sexual reproduction in genetic reorganization becomes even more important. Asexual recombination of higher plants generally can only be achieved under artificial conditions. This is the somatic cell fusion developed since the seventies, nuclear transfer, organelle exchange and other cellular engineering techniques.