玉米单倍体精准加倍效果及超快捷育种方法探讨

基于幼胚拯救的化学加倍技术路线，对难以自然加倍基础材料（华美1号）的单倍体进行精准加倍后，加倍株率高达75.83%，自交结实率高达50.39%，是自然加倍效率的49.89倍和69.97倍，多粒（≥7粒）结实果穗高达80.1%，提出单倍体人工精准加倍概念。多年实践发现，精准加倍能实质性改善单倍体散粉质量，花序表现为整分支或全序散粉，平均散粉期达4 d，抖花序就可采集充裕的花粉。开展以高通量幼胚拯救精准加倍与DH₀自交和测交同步实施为主要技术关键的“玉米超快捷育种方法及流程”研究取得重要成果，经多年规模化验证，关键技术指标达到8个月时限内完成DH系的创制、鉴选，并同步获得相应测交种，经过3年8个月时限即可育成优异组合进入预试，提出结合轮回选择的超快捷双轮回育种技术应用策略。

Discussion on the Effect of Precise Doubling of Maize Haploid and the Method of Ultra-Quick Breeding

The concept of haploid artificial precision doubling was proposed, based on the chemical doubling technology route of embryo rescue, selecting haploids that are difficult to spontaneous doubling as basic materials (Huamei 1), after precise doubling, the doubling rate up to 75.83%, seed setting rate up to 50.39%, which was 49.89 and 69.97 times of the natural doubling efficiency, respectively. Ears with more kernels''proportion is up to 80.1%. The study found that precise doubling can substantially improve haploid pollen production ability, more pollen can be collected easily. According to the above, the study on the method and procedure of ultra- quick breeding has been successful. The key step of''Ultra-quick breeding''is precise doubling of high-throughput embryo rescue is performed simultaneously with DH₀ self and testcrossing. After years of large- scale experiments vitrificated that complete the creation and selection of DH lines within 8 months, and obtain the corresponding test crosses simultaneously. After 2 years''yield trials, elite hybrids can be selected into National Registration Tests. At the same time, it proposed the strategy of ultra-quick breeding methods combine with double recurrent selection.