作物远缘杂交育种的途径及其实质

作物远缘杂交的育种可操作性及效果多年来颇有争议,科学家对物种起源与进化的研究恰恰是指导作物远缘杂交育种的理论基础。物种形成理论研究表明生命的共同起源是远缘杂交的理论基础,生物多样性是远缘杂交的物质基础。生物种间的繁殖隔离机制是远缘杂交不亲和性障碍的根源所在,而物种形成方式又为克服远缘杂交的不亲和性提供了理论依据。其中异域性物种形成方式下的生殖隔离具有不彻底性,是克服远缘杂交受精前不亲和性的理论根据;同域性物种形成方式中多倍体化的方式对远缘杂交受精后不亲和性的克服具有较强的指导意义。本文在通过对以上方面的阐述,剖析了远缘杂交的障碍来源、克服途径及实质,为作物远缘杂交育种工作提供参考。

Essences and Approaches of Distant Hybridization in Crops Breeding

There are many controversies over the operability and effectiveness of distant hybridization of crop breeding since many years ago, and the investigation of evolution and origin of species, are properly the theoretical basis for crops distant hybridization breeding. The theories of speciation indicate that the common original of life is the rationale of distant hybridization, and biodivcrsity is the material basis of distant hybridization. Reproductive isolation mechanism is an underlying cause of incompatibility barrier in distant hybridization, and the modes of spe-clarion provide theoretical foundation for the incompatibility of distant hybridization. Allopatric speciation is a gradual process, species may not yet bc fully separated, and this is the rationale of overcoming pre-fcrtilization in-compatibility of distant hybridization. Polyploidy is an example of sympatric spcciation, and is a great significance to post-fertilization incompatibility. In this article, we elaborated the above-mentioned and analyzed the origin of barriers, ways of overcome and the essences of distant hybridization, for providing references for distant hybridiza-tion breeding of crops.