【作者】 孟秋成；

【导师】 刘建丰； 刘二明；

【作者基本信息】 湖南农业大学 ， 作物遗传育种， 2009， 硕士

【摘要】 水稻是我国最重要的粮食作物。由子囊菌Magnaporthe grisea（Hebert）Barr[无性世代为Pyricularia grisea（Cooke）Sacc]引起的稻瘟病是我国水稻生产上最严重的病害。我国杂交稻面积已超过常规稻面积,到达60%以上。因此培育和种植抗稻瘟病的高产杂交稻组合对于保证我国的粮食安全和减少农业面源污染具有重要意义。新审定的水稻两用核不育系龙S具有株叶形态好、育性转换临界温度低、配合力好和高抗稻瘟病等特点,本研究对其稻瘟病抗性及杂种一代优势进行了研究,获得了如下主要结果:1、龙S对稻瘟病菌的抗谱较广并表现为高抗。2007年和2008年的抗性鉴定结果均证明,龙S对大部分接种菌株表现高抗,并好于广谱抗瘟基因Pi9的携带亲本75-1-127。2、龙S的稻瘟病抗性由主效显性基因控制。两年的结果均表明:无论配组所使用的父本品系对接种菌株表现抗、感或高感,龙S的杂种一代均表现高抗。3、龙S与感病亲本CO39和R599的2个杂种F₂代群体用稻瘟病菌株RB13进行接种鉴定,抗病和感病的分离比分别为259:91和323:119,经卡方检验符合3:1分离,说明龙S对菌株RB13的抗性表现为由一对核基因控制的显性遗传。4、龙S的杂种一代单株产量显著超过对照,比对照增产的主要原因是每穗粒数的增加,比Y58S杂种一代增产的主要原因是千粒重较高,比广占63S杂种一代增产的主要原因是单株穗数较多。5、龙S在单株产量、单株穗数、每穗粒数和生物产量上的一般配合力值高于Y58S和广占63S,杂种一代表现有效穗多、每穗粒数较多和产量较高。龙S杂种一代在单株穗数、每穗粒数、结实率、充实度、千粒重和生物产量上表现较大的特殊配合力方差,说明所配组合在性状上的选择余地较大,可以根据育种目标选择不同的父本,配组出不同类型的组合,既可以选配出多穗类型的组合,也可以选配出大穗或千粒重较高的组合。6、单株产量、千粒重、生物产量和穗长主要受控于不育系的一般配合力,并主要由不育系的加性效应决定,单株穗数、每穗总粒数和每穗实粒数主要由父本的加性效应决定,株高、充实度和结实率主要由双亲的特殊配合力决定。因此不育系和恢复系较好的产量性状基础是超高产两系杂交稻选育的关键。更多还原

【Abstract】 Rice is the most important crop in China. Rice blast ,caused by Magnaporthe grisea, is one of the most serious disease to rice production. The area of hybrid rice, reaching to more than 60% of the conventional rice area in China, is larger than that of inbred rice. Therefore, breeding and planting high-yielding hybrid rice with resistance to rice blast is very important to food safety and decreasing environment pollution. Long S, a dual-purpose genic male sterile rice newly registered, has comprehensive characteristics of good plant type, low critical sterility inducing temperature, good combining ability and broad-spectrum blast resistance .The resistance genetics of rice blast and combining ability in Long S were studied in this paper. The main result are:1) Long S is highly resistant to all strains used in the experiment in the year of 2007 and 2008, and better that of 75-1-127 which carries Pi9.2) All hybrids of Long S is highly resistant to the strains used in the experiment in the year of 2007 and 2008 whenever the restorer line of the hybrid combination is resistant or highly sensition to the strains, meaning that the resistance of Long S to the used blast race was controlled by dominant genes.3) The F₂ generations of two combinations , Long S/CO39 and Long S/R599,were inoculated with blast strain RB13 to study the resistance genetics of Long S. The results showed that the segregation ratio of resistance and susceptiblity to RB13 was 259:91 and 323:119 in F₂ population respectively,in accordance with 3:1 by Chi-square testing, meaning that the resistance to blast race RB13 of Long S was controlled by one dominant gene.4) Grain weight per plant（ GWP）of the hybrids of Long S has a significant increase over the check because of greater advantages in spikelets per panicle （SP ）,over the hybrids of Y58S mainly because of increasing in 1000-grain weight （TGW）,over the hybrids of Guangzan 63S mainly because of increasing in panicles per plant（PP） . 5) The general combining ability （GCA） of Long S was better than that of Y58S and Guangzhan 63S in GWP, PP, SP and biomass. The hybrids of Long S had greater variance of special combining ability（SCA） in PP, SP, TGW , seed setting percentage, grain pumped degree and biomass. These results showed that the hybrids of Long S can have much panicles or big panicles or big grains by choosing different restorer line.6) The additive effects from the dual-purpose genic male sterile rice were principal in GWP, TGW, biomass and panicle length .On the other hand, the additive effects from the restorer line were principal in PP and SP. The results showed that excellent yielding traits of the PTGMS line and restorer line are the key to breed super hybrid rice.更多还原