向日葵杂种生产采用三系配套系统完成。因此，向日葵细胞质雄性不育性的研究备受关注。其中研究较为清楚的是PET1细胞质，其不育机理是线粒体DNA重组形成嵌合基因，编码新的多肽，导致小孢子的败育。然而，这些基因如何影响小孢子发育的生理机制仍不清楚，有待进一步深入研究。丰富多样的向日葵CMS会大大降低因遗传单一性给大规模生产带来的风险；未发现恢复系的CMS可以用于无花粉观赏向日葵杂交种的生产。
Sunflower (Helianthus annuus L.) is one of four main oil crops in the world and its hybrid production depends on three lines (sterile line, maintainer line and restoring line). That is why cytoplasmic male sterility (CMS) in sunflower is the research focus through years. The sterility mechanism of PET1, the single source of hybrid breeding of sunflower, is the occurrence of chimeric genes resulting from the intramolecular recombination in mitochondrial genome. As a result, the chimeric gene encoded a new polypeptide which impair the development of male gamete. The physiological mechanisms by which the products of these genes interfere with the formation of male gametophytes are still the subject of intense research. Variable germplasm of CMS would decrease the crisis of single source for hybrid production, and make lots of sense in ornamental sunflower as well.
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