几个籼型三系杂交水稻亲本的配合力及遗传力分析

选用 7个不育系和 7个恢复系以不完全双列杂交 (NCII)模式配制 4 9个组合 ,研究了 15个主要农艺性状的配合力和遗传力。结果表明 1在株高、粒长、粒宽、长宽比、每穗总粒数、着粒密度、结实率等性状上基因加性效应占主导地位 ;在单株有效穗、主茎剑叶长 ,穗长、每穗实粒数、千粒重、单株产量、相对日产量等性状上则以基因的非加性效应为主。 2大多数农艺性状受恢复系的影响要比受不育系的影响大得多 ,仅少数几个性状 (穗长、粒宽、长宽比和千粒重 )受不育系的影响稍大。3参试的不育系以浙农 80 10 A、协青早 A和全龙 A较好 ,恢复系以 J4 13、明恢 6 3选、95 - 13和 M10 5为较好 ;在 4 9个组合中浙农 80 10 A×明恢 6 3选是一个综合性状表现较为出色的组合。 4各性状的狭义遗传力由大到小的趋势为 :长宽比 >粒长 >着粒密度 >株高 >粒宽 >每穗总粒数 >播始历期 >结实率 >每穗实粒数 >主茎剑叶长 >千粒重 >穗长 >单株产量 >相对日产量 >有效穗。     

华南籼型三系杂交水稻主要品质性状的配合力分析

选用华南地区广泛应用的6个不育系和6个恢复系,以不完全双列杂交配制36个杂交组合,研究了12个品质性状的配合力。结果表明,12个品质性状一般配合力方差和特殊配合力方差均达到了显著或极显著水平,说明这些性状同时受基因的加性和非加性效应的共同作用,且均以加性效应占主导地位。亲本的一般配合力与组合特殊配合力在各性状上都是相互独立的,没有明显的对应关系。在对亲本主要品质性状的综合评价上,供试的不育系以双青A最好,万金A、博A、Ⅱ-32 A较好;恢复系以广恢998、桂99最好,HR 15较好。     

籼型三系杂交水稻主要农艺性状配合力研究

选择具有广泛代表性的6个不育系和9个恢复系，采用NC II交配设计分析12个农艺性状的配合力。结果表明：①除主茎剑叶长、结实率和千粒重三性状非加性效应不明显外，其他性状的加性效应和非加性效应均有显著作用，且均以加性变异为主，但单株产量、相对日产量及单株穗数三性状非加性变异较大。②主茎剑叶长、穗长和千粒重三性     

籼型杂交水稻光合性状的配合力及遗传力分析

利用籼型水稻4个不育系和4个恢复系配组的4×4NCII交配设计,对其光合性状的配合力及遗传力进行分析.结果表明,(1)在叶绿素含量、饱和光强、量子效率、CO2补偿支、光合功能期、叶片寿命等性状中,亲本的基因加性效应对杂种一代性状形成起主导作用;在光合速率和气孔导度等性状性,遗传变异主要来自基因的非加性效应.(2)光合速率、     

稻谷整精米率的测定

对《稻谷整精米率检验法》新旧标准进行了系统的对比分析,结合实际工作,阐明应正确理解和掌握净稻谷、整精米、整精米率等定义及选择符合标准要求的砻谷机、实验碾米机才能全面正确的实施新标准。     

籼型杂交水稻农艺性状的配合力研究

如何有效利用杂种优势已成为水稻增产的关键。本研究按照NCII遗传交配设计,将三系野败型杂交水稻的恢复系和微核心种质构成的115份优异籼稻品种,分别与4个两系不育系及1个三系不育系测交,分析各农艺性状配合力、遗传力及相互关系。结果表明,除单株有效穗数、主穗实粒数外,其他农艺性状一般配合力差异均达到极显著水平;除单株有效穗数外,其他各农艺性状特殊配合力差异也均达到极显著水平。同一组合的不同性状、同一亲本的不同组合所表现出的特殊配合力效应都有所不同,表明亲本的一般配合力水平与特殊配合力间没有固定的联系。在育种实践中,选取一般配合力高的亲本,同时兼具较高特殊配合力是获取高产杂交稻组合的关键。     

稻谷整精米率检验操作之探讨

整精米率作为稻谷的一项定等指标 ,是以 2 0 0 0年度起执行新的稻谷国家标准ＧＢ135 5 - 1999为标志而广泛使用的。由于影响整精米率的因素比出糙率更多 ,因此 ,增加整精米率检验项目与以前单纯用出糙率定等相比 ,更能体现稻谷的生化特性和加工食用品质 ,促进粮食种植结构的调整。整精米率在粮食流通特别是购销环节中 ,由于流通量大 ,且时间集中 ,检验以仪器检验为主 ,因此 ,规范仪器检验的操作方法显得尤为重要。1　影响整精米率检验准确性的因素1 1　非操作因素1 1 1　品种及粒型 (即长宽比 )　长宽比较大的籼型稻谷耐压力和稳定性较差 ,…     

Optimizing selection for rough rice yield, head rice, and total milled rice

High rough rice yields are important for the profitable production of rice (Oryza sativa L.). The value of rough rice is determined primarily by head rice (whole milled grains) and broken rice, together referred to as total milled rice. The objective of this study was to optimize selection for rough rice yield, head rice, and total milled rice using path-coefficient analysis and selection indices. Thirty-seven long grain pure lines were grown in an experiment at three Arkansas locations during 1993 and 1994. In another test, twenty-eight F₁ hybrids obtained from an eight-parent half diallel of long-grain rices were grown at two locations in Arkansas during 1991. For the pure lines, path analysis revealed that rough rice yield was approximately twice as important in determining total milled rice/ha than head rice. Path analysis for the hybrids revealed that rough rice yield was an even greater component in determining total milled rice/ha. Based on yield components for hybrid rice, panicle density had the largest direct effect determining total milled rice/ha. Filled grain/panicle, grain weight, and head rice, in that order, were secondary, but positive, factors determining total milled rice/ha. A selection index for pure lines based only on selection for head rice was 19.2 percent as effective as selection for total milled rice/ha directly. When selection for total milled rice/ha was based solely on rough rice yield, selection was 82.7 percent as effective as selecting for total milled rice/ha directly. Selection to improve total milled rice/ha should concentrate on increasing both rough rice yield and head rice. Rough rice yield should receive greater priority than head rice in selection strategies. This revised version was published online in July 2006 with corrections to the Cover Date.     

三系杂交稻川谷优1378的选育与应用

川谷优1378是贵州省铜仁科学院用自育的三系恢复系R1378与四川农业大学水稻研究所选育的不育系川谷A配组育成的高产、优质、迟熟杂交晚稻新组合。2016年3月通过贵州省农作物品种审定委员会审定(黔审稻2016003)。对川谷优1378的选育过程、品种特性以及栽培和制种技术要点进行了介绍。     

籼型杂交水稻新组合试制技术初探

新组合试制是水稻育种过程中不可缺少的重要环节，可为新组合参加各种试验示范提供高纯度参试种，同时通过观察亲本制种特性，为大面积生产提供基本数据、降低生产风险，对一个品种的选育和推广应用起着非常重要的作用。     

小麦茎秆特性的配合力分析

随机选用8个亲本组配成一套双列杂交组合，研究了普通小麦茎秆特性的配合力。结果表明，基部第1节间茎粗的GCA差异极显著，但SCA差异未达显著，为加性模型遗传；其余节间茎粗和所有节间长的GCA和SCA差异都达到了极显著。均受加性效应和非加性效应的的共同作用，但以加性效应为主。各性状亲本的GCA效应与表现型值都呈正相关；同一性状中SCA效应大的杂交组合，一般至少有一个亲本的GCA效应最大或接近最大；相反，同一性状中SCA效应小的杂交组合，一般都有一个亲本的GCA效应为负且绝对值较大。节间长的hB2为98.5%－99.7%，hN2为63.9%-90.0%；茎粗的hB2为79.3%-92.4%，hN2为59.9%-73.4%。节间长的选择响应依节位自上而下递减，而茎粗则相反，依节位自上而下递增。最后，依据亲本的一般配合力效应和特殊配合力方差评价了亲本。依据性状的遗传特点讨论了后代选择、育种目标和亲本选配等问题。     

Genetic diversity, hybrid performance, and combining ability for yield in Musa germplasm

Genome size variation occurs within and across generations in Musa spp., which reduces the predictive accuracy of parental performance on progeny value for yield and other traits with complex inheritance. Parental selection through progeny testing of prospective parents is required to achieve further genetic gains. This was carried out in this study, using a factorial mating design involving five 4x females and five 2x males. Genetic differences among offspring families were essentially due to differences in additive effects of the parents. Thus, little recombinative heterosis can be expected upon 4x-2x cross-breeding, and breeding strategies should target the development of 4x and 2x cultivars by accumulation of favorable alleles through recurrent selection within each ploidy pool. Offspring yield was positively correlated with parental GCAs but not with mid-parent values. Hybrid performance was also associated but not significantly correlated with genetic similarity indices based on both pedigree and molecular data. This study further suggests that current genetic models may not be adequate for populations with intergeneration genome size polymorphism. This revised version was published online in July 2006 with corrections to the Cover Date.     

Breeding and combining ability of heterostylous genotypes for hybrid seed production in Lycopersicon esculentum Mill

Summary A subjective rating scale was used to select tomato inbreds with inserted stigmas (inserted) for crossing with inbreds possessing exserted stigmas (exserted) in a combining a bility study. Six inserted parents were inbred to F₅ or F₆, but were not stable for stigma position in most cases. The exserted x inserted hybrids were all slightly exserted and it appeared stigma exsertion was incompletely dominant to stigma insertion. No reciprocal cross differences were detected for stigma position indicating the absence of cytoplasmic inheritance. There was no clear relationship between hybrid stigma positions and the level of insertion of the inserted parents. Stigma insertion was more consistently detrimental to fruit set than was stigma exsertion. Hybrids were either heterotic or dominant for yield.The inability to attain hybrids with standard stigma positions by crossing exserted x inserted genotypes could limit fruit-set under some environmental conditions. Furthermore, difficulty in breeding stable inserted lines and the incomplete dominance of exserted over inserted genotypes limits the feasibility of using heterostyly alone for producing reliable hybrids.Ohio Agricultural Research and Development Center Article No. 166-78.     

Parental genetic distance and combining ability analyses in relation to heterosis in various rice origins

Journal of Crop Science and Biotechnology - Information on parental genetic distance and combining ability is a fundamental prerequisite for hybrid rice breeding. Based on a study of genetic...     

Estimates of combining ability for resistance of winter rye to Fusarium culmorum head blight

Summary Head blight caused by Fusarium culmorum and F. graminearum is damaging in all winter rye (Secale cereale L.) growing areas. For hybrid breeding, the relative magnitude of general (GCA) and specific combining ability (SCA) is a crucial parameter for developing appropriate selection procedures. Forty single-cross hybrids were produced by crossing six and seven inbred lines of the Petkus and Carsten gene pool, respectively, in a factorial design. Hybrids were evaluated in two years with artificial F. culmorum inoculation. Resistance traits were head blight rating and grain weight relative to the non-inoculated control. Both resistance traits were closely correlated across both years (r-0.8, P=0.01). Significant genotypic variation was found for both traits with medium to high estimates of heritability (h²=0.6-0.8). Components of variance for GCA were, across years, 10 and 6 times larger than those for SCA for head blight rating and relative grain weight, respectively. Significant SCA effects were found for 15 to 20% of all cross combinations across both traits in each year. SCA effects were, however, inconsistent over years leading to a high SCA-year interaction. In conclusion, resistance to Fusarium head blight among the interpool hybrids tested was conditioned mainly by additive gene action that could be utilized by recurrent selection in multi-environment trials.Abbreviations GCA general combining ability - SCA specific combining ability     

基于通路分析剖析水稻农艺性状配合力和杂种优势

按照NCII遗传交配设计构建测交群体,考察包括产量性状在内的9个农艺性状,对水稻农艺性状表型、配合力和杂种优势进行通路分析,以期为水稻品种的培育和改良提供理论基础。结果表明,主穗实粒数与生物调控、千粒重与半胱氨酸和蛋氨酸代谢、主穗长与SNARE相关囊泡运动、主穗一/二次枝梗与依赖DNA的转录、株高与大分子代谢过程、主穗颖花数与花粉识别、有效穗数与水解酶活性、单株实粒重与嘌呤核苷结合等通路相关。为获得优良性状,高配合力,杂种优势可以从某一性状的相关通路进行研究,找到调控该通路的相关基因,以期为改良水稻一般配合力和获得杂种优势提供一定帮助。