超级早籼稻“中早39”的高产育种研究

Research on High Yield Breeding of Super Early Indica Rice “Zhongzao 39”

利用高产早籼嘉育253和高产抗稻瘟病早籼品种中组3号为亲本,采用分离世代自然病圃鉴定结合稻瘟病混合菌株人工接种抗性筛选方法,通过系谱法和产量比较试验,最终选育获得高产抗稻瘟病早籼稻新品种中早39。对超级早籼稻品种中早39及其系谱亲本嘉育253和中组3号进行产量相关性状、光合特性、叶面积指数和光合色素含量等测定和比较分析,发现中早39的每穗总粒数和结实率优于其系谱亲本,库容优势明显;中早39在齐穗后20天保持最高的净光合速率,其叶面积指数和各光合色素含量也优于系谱亲本;因此,中早39具有超高产光合生理特性。育种初期选用了高产亲本,且在生育后期中早39比其系谱亲本具有更优的光合生理特性,是水稻高产育种中优良性状的整合和后期功能型超级稻特性的体现;中早39超高产优势来自于品种选育过程中源库的优化、株叶形态的改善;中早39的选育研究为水稻高产育种提供了参考信息。

Early Indica rice variety ＂Jiayu 253＂ and ＂Zhongzu 3＂ were used as parents to breed a new variety ＂Zhongzao 39＂ through pedigree method and yield comparison trial. Natural disease nursery and artificial inoculation of mixed strains of blast for each segregation generation were conducted. The variety ＂Zhongzao 39＂ and its pedigree parents ＂ Jiayu 253 ＂ and ＂ Zhongzu 3 ＂ were further compared on yield related traits, photosynthetic characters, leaf area indexes and photosynthetic pigment contents. Results showed that total grain number per panicle and seed setting rate of Zhongzao 39 were higher than that of its pedigree parents, indicating its excellent sink. The highest net photosynthetic rate of Zhongzao 39 was demonstrated 20 days after the stage of full heading stage. Its leaf area index and photosynthetic pigment content were showed the most high as well. Therefore, Zhongzao 39 demonstrated elite photosynthetic physiological characters for high yield. Using high-yield pedigree parents in breeding and integration of elite traits during breeding contribute to the high-yield of Zhongzao 39. The super high yield advantage is obtained from source sink optimization, improvement of plant leaf morphology and performance of late-stage vigor super hybrid rice characters during rice breeding, which gives reference information for rice high-yield breeding.