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一、意义 由“种间隔离”机制所造成的杂交不亲和性,是进行植物远缘杂交的主要障碍之一。从三十年代以来,不少遗传学家和育种工作者对远缘杂交的不亲和性问题及其克服方法作了系统的研究和大量的试验。目前,国内外报导克服远缘杂交不亲和性的几种方法是:一般生物学方法;化学因素刺激法;桥梁法;组织培养法的改进等。 由于这些方法的采用,人们打破了物种进化中造成的种间关闭状态,创育出不少远缘杂种。但尽管如此,目前远缘杂交的结实率仍然很低,一般都在1％上下,结实率超过10％的报导甚少。而且这些杂种多不是真正的精卵结合,大多数是部分的精卵或DNA片断的结合。无疑这给我们提供的选择机率仍然是太微小了。为了充分发挥远缘杂交在育种中的作用,更显著地扩大和丰富作物育种的基因库,促进种间基因交流,培养出更多对人类有用的新物种,进一步开展对远缘杂交不亲和性及其克服方法的研究,仍是一项重要的课题。
First, the significance of the “interspecific segregation” mechanism caused by hybrid incompatibility, is one of the major obstacles to plant distant hybridization. Since the 1930’s, many geneticists and breeders made systematic research and a large number of experiments on the incompatibility of distant hybridization and its overcoming methods. At present, several methods of overcoming the incompatibility of distant hybridization are reported at home and abroad: general biological method; chemical stimulation; bridge method; and the improvement of tissue culture method. Due to the adoption of these methods, people broke the state of species closures caused by species evolution and created many distant hybrids. In spite of this, the seed setting rate of distant hybridization is still very low, generally 1% up and down, and the rate of seed-setting exceeding 10% is poorly reported. And more of these hybrids are not true sperm-egg combination, most are part of the combination of sperm or DNA fragments. There is no doubt that this gives us the chances of choice is still too small. In order to give full play to the role of distant hybridization in breeding, more significantly expand and enrich the gene pool of crop breeding, promote interspecific gene exchange, cultivate more new species useful to human beings, and further develop incompatibility of distant hybridization The study of sex and how to overcome it is still an important topic.