【作者】 周六斤；

【导师】 陆作楣；

【作者基本信息】 南京农业大学 ， 作物遗传育种， 2004， 硕士

【摘要】 恢复系×恢复系是目前杂交稻选育恢复系的主要途径。一般方法是根据农艺性状进行选择，待基本稳定后再进行测配；前期以表型选择为主，后期配合力选择为主，但是表型选择与配合力选择并不完全一致，有时甚至结果相反。如果前期提高表型选择标准，高配合力的材料可能早早就被淘汰；但若把表型选择标准放宽，前期选择及后期的测配工作量都很大，育种效率不高。本文借鉴杂交玉米育种中的配子选择法，设计了6311S配套恢复系选育的组合判别法研究，尝试在恢复系选育的早代进行配合力选择，提高组合早代的筛选效率。试验利用8个恢复系亲本按双列杂交法配制26个单交F₁，然后再与两用不育系6311S杂交配制三交组合。对26个单交F₁的主要性状进行分析；并分析了三交组合的农艺性状和部分品质性状，研究了三交组合和对应父本F₁之间的性状相关性；同时对8个亲本恢复系和26个单交F₁进行配合力分析，研究了它们与单交F₁的性状表现及其现实配合力之间的关系；对6311S配套恢复系的早代筛选做了初步探讨。结果表明： 1、根据三交组合的表现，筛选出5个现实配合力好的单交组合，即玉18／绵恢725、绵恢725／9311、9311／紫66、绵恢725／紫66和测253／CDR22，从它们后代中选育出6311S配套恢复系的几率要高。 2、恢复系间单交F₁的性状分析得到6个农艺性状表现优良的组合：9965／紫66、9311／CDR22、351／紫66、玉18／紫66、测253／CDR22、351／9311，只有测253／CDR22的现实配合力较高。 3、紫66、351、CDR22、9311的单株产量一般配合力较好；测253／CDR22、9965／玉18、9965／紫66、351／绵恢725、绵恢725／紫66、9311／CDR22等组合的特殊配合力效应值较高。恢复系间单交F₁的主茎穗总粒数、实粒数、结实率、有效穗数和单株产量以基因的非加性效应为主，千粒重性状以基因的加性效应为主；而表型选择的6个组合中，351／紫66单株产量双亲的一般配合力起着主要作用，其它组合的单株产量组合特殊配合力起着主要作用。 4、配合力选择的5个F₁中，4个中选F₁的双亲中至少有一个一般配合力高的亲本，但是除三交F₁的实粒数与单交组合的特殊配合力呈显著负相关，恢复系亲本的一般配合力与三交组合的千粒重达极显著正相关外，并未发现恢复系亲本的一般配合力和单交组合的特殊配合力与三交F₁单株产量在内的其它性状之间有明显的相关关系，说明亲本间杂交的配合力分析并不能替代组合判别，从而证实了组合判别法必要性。周六斤硕士学位论文:63115配套恢复系选育的组合判别法研究5、本研究在恢复系选育的早代进行配合力选择，单交组合淘汰率高达80%以上，可以把有限的人力物力集中于少数几个有希望的组合，大大降低了工作量，提高了组合筛选的效率，为恢复系的选育提供了一个快速、有效的方法.更多还原

【Abstract】 The general method of breeding new restorer lines is to select from two restorer lines cross descendants by phenotypic characters in early generations and by Combining ability in late generations. The effect was not satisfying, because phenotypic selection and combining ability selection can not fit well, sometimes the results were opposite , if phenotypic selection was strict in early generation, materials with good combining ability would be lost earlier; but if the criterion of phenotypic selection was wide, the workload both in early and late generations would be very large. Combination screening method in breeding restorer lines for 6311S was studied according to gamete selection in maize breeding. 26 F1 were derived from 8 restorer lines by Griffing IV design, then 26 triple cross hybrids were obtained from 26 FI and 6311S. Important characters of single cross hybrids and triple cross hybrids.combing abilities of 8 restorer lines and 26 single cross hybrids were analyzed. Meanwhile, the correlations between combing abilities and yields of single cross hybrids and triple cross hybrids were studied. The results were as follows:1. 5 FI were selected from 26 FI based on important characters of triple cross hybrids. They were Yul8/MianHui725, MianHui 725/9311, 9311/Zi66, MianHui725/Zi66, Ce253/CDR22, from which the probability of breeding new restorer lines for 6311S might be high.2. According to phenotypic characters of single cross hybrids. 9965/ZJ66. 9311/CDR22, 351/Zi66,Yul8/Zi66,Ce253/CDR22,351/9311 were chosen. Phenotypic selection and combing ability selection got different results.3. 351. 9311, Zi66 and CDR22 had good GCAs; Ce253/CDR22. 9311/CDR22. 9965/Zi66, 351/Mianhui725 and 9965/Yul8 had good SCAs in yields.The non additive variation was principal for spikelets per panicle , filled spikelets per panicle, seed setting rate, and grain weight per plant of single cross hybrids: while the additive variation was greater for only 1000-grain weight. Among 6 FI selected by phenotypic selection, GCAs play more important role in the yield of 351/Z166. But SCAs play more important roles in the yields of the rest.4. SCAs of 5 F1 selected by combining selection were different, among the restorer lines of 4 hybrids, at least one had high GCA . but the correlations between parents’ GCAs and triple cross hybrids’ yields were not found.5. These results suggest that Combing ability selection in early generation might be a quick and effective method of breeding restorer lines.更多还原