Genetic analysis for protein content in indica rice

Analysis of genetic main effects and GE interaction effects for protein content (PC) and protein index (PI) of indica rice (Oryza sativa L.) was conducted for two year experimental data by using a genetic model for quantitative traits of seeds in cereal crops. Nine cytoplasmic male sterile lines or maintainers as female parents and five restorer lines as male parents were used for a NC II mating design in 1995 and 1996. The results indicated that PC and PI traits were simultaneously controlled by genetic main effects as well as GE interaction effects. For PC and PI of rice, the embryo interaction effects (embryo additive and dominance interaction effects) were important as effects of triploid endosperm, cytoplasm and diploid maternal plant. The estimates of narrow-sense heritability for PC and PI of rice were 85.3% and 77.9%, respectively. The interaction heritability was found to be larger than the general heritability for PC and PI of rice. Significant relationships for components of different genetic effects between PC and PI were found. The GE interaction covariances tended to be positive. This revised version was published online in July 2006 with corrections to the Cover Date.     

红花双列杂交后代羟基黄色素A含量的遗传效应分析

选用6个羟基红花黄色素A（HSYA）含量差异较大的亲本,采用双列杂交方法配制杂交组合,测定2015年和2016年2年亲本及其后代F₁和F₂红花中的HSYA含量。运用双子叶植物种子数量性状遗传模型和统计分析方法,分析胚、细胞质和母体植株3套遗传体系的基因效应和环境互作效应。结果发现：在HSYA含量的遗传体系中,母体遗传效应影响最大,胚效应次之,细胞质效应影响最小。3套遗传体系均表现出基因主效应大于环境互作效应。机误方差较大,说明HSYA含量还受环境机误或抽样误差的影响。亲本遗传效应分析表明,豫红花1号（P₁）做亲本表现稳定,有利于增加杂交后代HSYA含量,达到提高品质、改良品种的效果。胚显性方差和母体显性方差均达到极显著水平,表明同时存在种子杂种优势和母体杂种优势,而且其主效应基因不受环境影响。综合考虑遗传主效应、胚显性效应和母体显性效应,亲本组合（P₁×P₅）有利于提高后代杂交品种的HSYA含量。该研究结果可为后代材料在杂种优势利用中的亲本选择提供理论支持。     

优质蛋白玉米产量和品质性状配合力、杂种优势及相关分析

以3个优质蛋白玉米自交系（♀）和5个优质蛋白玉米自交系（♂）为试验材料,按照NCⅡ遗传交配设计组配成15个杂交组合,对其主要性状的配合力、杂种优势及其间相关进行分析。结果表明：①同一性状不同材料间,同一材料不同性状间其配合力效应表现复杂,存在不同效应大小和正负作用方向的差异,父本A粒深、容重的一般配合力均较高;母本2赖氨酸含量的一般配合力较高;组合3×C容重的特殊配合力较高。②小区产量与粒深、穗粗呈极显著正相关;赖氨酸含量与粗脂肪含量呈极显著正相关,与粗蛋白含量呈显著正相关。③赖氨酸含量、粗蛋白含量以超低亲杂种优势为主;粗淀粉含量以超中亲优势为主;粗脂肪含量以超高亲优势为主。     

Genetic analysis of methionine content in indica-japonica hybrid rice (Oryza sativa L.) at different grain developmental stages

Genetics of methionine content in indica-japonica hybrid rice (Oryza sativa L.) was studied in 35 F₁ hybrids derived from crossing 7 male-sterile indica rice cultivars with 5 restorer japonica rice cultivars. Two genetic models and their corresponding statistical methods for quantitative traits of triploid endosperm in cereal crops were used for the analysis. One is the unconditional model, which refers to the analysis of cumulative measurements along the developmental stages, while another is the conditional model, which relates to analysis throughout the developmental stages. Results showed that methionine content of indica-japonica hybrid rice was controlled by expression of triploid endosperm nuclear genes, cytoplasm genes, diploid maternal plant nuclear genes, and their genotype-environment interaction effects. Dominant effects were important at the first three developmental stages, while additive effects were important at the next two stages of grain development under both unconditional and conditional analyses. With regard to the components of heritability, maternal and cytoplasm general heritabilities and their environmental interaction heritabilities were important. It was suggested that enhancing methionine content could be more efficient when selection is based on maternal plants in early breeding generations.     

Genetic effects of embryo and endosperm for four malting quality traits of barley

Seed of seven cultivars of two-rowed barley (Hordeum Vulgare L.) and F2 seed from a half-diallel set of crosses among the cultivars were malted in two years to obtain data on diastatic power (DP), alpha-amylase activity (αAA), beta- amylase activity (βAA) and malt nitrogen (N) content. Embryo and endosperm genetic effects on the traits were studied by using a genetic model including genotype × environment interaction for malting quality characters. Variation of the four malting quality traits was affected by gentic effects and environmental interaction. Performance of DP and βAA was mainly controlled not only by endosperm dominance effects but also by embryo genotype × environment interaction and endosperm dominance × environment interaction. Variation of αAA and malt N content was controlled by both embryo and endosperm genetic effects, but the embryo dominance and endosperm additive effects contributed a major part to the total genetic effects. Significant interaction variances (embryo additive × environment and dominance × environment and endosperm dominance × environment) were also observed for αAA and malt N content. Diastatic power was related positively to βAA. Malt N content was associated positively with DP, largely because of the relationship between malt N and βAA. No obvious phenotype association between DP and αAA was found. General narrow-sense heritabilities of αAA and malt N content were 26.1% and 27.8%, respectively. This revised version was published online in July 2006 with corrections to the Cover Date.     

棉花三系杂交种不同生态区遗传效应及优势表 现简

 选用3个核背景不同的恢复系材料和7个不同的哈克尼西棉胞质不育材料作为亲本,根据NCⅡ遗传交配设计,配置了21个杂交组合,分别在黄河流域棉区河南安阳、黄淮流域棉区河南西华和长江流域棉区安徽无为3个生态区试点种植,通过性状调查与室内考种,采用朱军的ADE模型,进行数据分析。结果表明,子棉和皮棉产量主要受到加性、显性、加性与环境互作效应的影响,衣分和铃数主要受加性、加性与环境互作效应的影响,而铃重则只受加性与环境互作效应的影响;对于纤维品质性状,纤维长度、马克隆值、比强度和整齐度受到加性效应的影响,同时,纤维长度和马克隆值还与加性与环境互作效应相关;遗传率分析与遗传方差分量分析表现一致;产量及产量性状之间有一定的遗传相关,而纤维品质性状之间的遗传相关则较小,产量和纤维品质性状之间也存在着较少的遗传相关;杂交组合的产量竞争优势表现为安阳试点>西华试点>无为试点,说明与生态环境有关。在3个不同的生态区,研究了21个杂交组合的遗传效应及优势表现,研究结果对三系杂交组合选配有一定的指导意义。     

籼粳交稻米品质性状杂种优势的遗传分析

用胚乳性状遗传模型和分析方法对籼粳交稻米品质性状的杂种优势进行了遗传分析,结果表明：各品质性状都具有一定的杂种优势,其中碱消值和蛋白质含量的优势较强。直链淀粉含量和胶稠度的优势较弱。不同性状杂种优势的遗传原因不同,直接显性和母体显性对杂种优势的贡献大小因性状而异,但总的来说,母体显性对籼粳杂种Ｆ２籽粒品质性状的杂种优势具有重要的意义,细胞质效应对部分性状（如胶稠度、蛋白质含量）的群体平均优势有一定     

Relationship between molecular marker heterozygosity and hybrid performance in intra- and inter-subspecific crosses of rice

The objective of this study was to investigate the relationship between molecular marker diversity and heterosis in both intra-and inter-sub-specific hybrids of rice to evaluate the feasibility of predicting hybrid performance using molecular markers. Eleven elite lines were intermated resulting in a diallel set including 10 indica × indica, 15 japonica × japonica and 30 indica × japonica crosses. The F₁ hybrids and parents were evaluated for agronomic performance in a replicated field trial. The parental lines were tested for DNA polymorphisms with 113 restriction fragment length polymorphism (RFLP) probes covering the 12 rice chromosomes. Inter-subspecific crosses showed better performance and higher heterosis than intrasubspecific hybrids. Correlations of marker heterozygosity with hybrid performance and heterosis differed considerably between the two subspecies; they were higher in crosses within japonica subspecies than within indica subspecies. Very little correlation was detected in intersubspecific crosses. It was concluded that relationships between marker heterozygosity and hybrid performance were complex owing to germplasm diversity and the complexity of the genetic basis of heterosis. The implications of the results in predicting hybrid performance using molecular markers are discussed.     

大豆籽粒异黄酮含量的遗传效应研究

大豆异黄酮含量差异较大的6个大豆品种为亲本，通过双列杂交配置杂交组合，测定了两个环境条件下亲本、F₁和F₂种子的异黄酮含量。采用双子叶植物种子数量性状遗传模型和统计分析方法, 分析了胚、细胞质和母体植株等不同遗传体系的基因效应以及环境互作效应。结果发现大豆籽粒异黄酮含量的表现主要受制于母体遗传效应, 其次为胚(子叶)基因效应,细胞质效应影响较小。不同遗传体系的基因主效应明显大于环境互作效应。异黄酮含量的机误方差较大,说明异黄酮含量更易受到环境条件变化影响。亲本遗传效应分析表明, 选用豫豆29或郑90007亲本有利于增加杂种后代大豆籽粒异黄酮含量,提高品质改良的效果。胚显性方差和母体显性方差均极显著，表明种子杂种优势和母体杂种优势会同时存在，而且是不受环境影响的主效应基因。     

Combining ability for yield,protein and oil of peanut lines from South American centers of diversity

Summary Ten peanut (Arachis hypogaea L.) lines, two from each of five centers of diversity in South America, and the F₂ generation of all possible crosses among them were used to characterize the variation for yield, fruit and seed traits and protein and oil content and to determine the breeding potential of the parents. Two of the parental lines belong to subspecies hypogaea and the other eight to subspecies fastigiata.Several crosses gave heterotic responses for yield. The parents of the crosses with significant heterosis generally came from different centers of diversity.Variation among both general and specific combining abilities was significant for all traits with the exception of the SCA estimate for protein percent. The component of variation for GCA was larger than the SCA component for all traits.A Spanish line and a Valencia-like intermediate line from the Guarani region had the highest GCA effects for fruit yield, seed yield and meat content and transmitted consistently their characteristics to their F₂ progeny. Some lines showed significant but small maternal effects for oil, protein and oil + protein percent. Differences between reciprocal crosses were significant for fruit length, fruit weight and oil + protein percent.A significant portion of the variation among crosses was explained by differences among parental lines within centers of diversity. This supports the fact that centers are founded because of the diversity of the peanuts grown there.The performance of parental lines per se was useful in predicting the performance of the lines in hybrid combination for all traits except fruit yield.Paper number 6141 of the Journal Series of the North Carolina Agricultural Research Service (USA). This work was partially supported by CSRS Research Agreement 701-15-51.     

Heterosis in crop mutant crosses and production of high yielding lines using doubled haploid systems

Heterosis appearing in crosses between mutants derived from the same parent variety and crosses of mutants with parent varieties has been observed by many authors for many plant species including such important crops as barley, faba bean, maize, pea, pearl millet, rice, sunflower, sesame, sweet clover, triticale and wheat. Mutant heterosis was reported for crosses of spontaneous mutants, mutants obtained after treatment with various mutagens and recently also for somaclonal variants. The heterotic effects are usually related to an increase in some yield components. There is a lack of correlation between mutation of a particular plant character and appearance of heterotic effect. The yielding performance of a mutant was not correlated with its potential to give yield heterosis in crosses with another mutant, often also a very poor one, or with the parent variety. Poor yielding barley mutants from the collection of semi-dwarf forms of the Department of Genetics, Silesian University gave heterosis in crosses with other mutants or parent varieties for such characters as tillering, grain number and weight per plant. In addition to mutants with deleterious mutations of such characters as chlorophyll synthesis or fasciated stem there were also lines mutated for earliness, semi-dwarfness, low glucoside or high protein and lysine content which gave significant heterosis in crosses. One possible explanation of the phenomenon of mutant heterosis is related to the frequency of mutations induced by chemical and physical mutagens. The appearance and the level of heterotic effect of mutated genes will depend on their interaction with other mutated genes or with genes from the parental genotype. High specific combining ability of mutants giving heterotic effect makes hybrid seed production, based on crosses with defined sources of cytoplasmic or genetic male sterility, unfeasible or even impossible. Doubled haploids provide a unique system to attempt the ‘fixing’ of hybrid performance in homozygous lines and to avoid the step of hybrid seed production. The assumption on the ‘fixability’ of hybrid yield in homozygous lines based on reports that large additive genetic variance is responsible for yield heterosis in wheat or barley was proven also for mutant crosses. This revised version was published online in August 2006 with corrections to the Cover Date.     

不同环境条件下稻米组氨酸和精氨酸的胚乳和母体植株QTL分析

利用汕优63重组自交系与双亲回交产生的BC1F1和BC2F1群体,采用新发展的包括环境互作效应在内的多遗传体系QTL作图方法和基因定位软件,对稻米两种半必需氨基酸（组氨酸和精氨酸）进行三倍体胚乳和二倍体母体植株等不同遗传体系的QTL定位分析。共检测到10个控制组氨酸含量的QTL以及8个控制精氨酸含量的QTL。全部QTL均具有极显著的三倍体胚乳和二倍体母体植株基因的加性主效应,其中4个QTL具有显著或极显著的三倍体胚乳显性主效应,7个QTL还具有明显的环境互作效应。     

Effects of cytoplasm on heterosis and combining ability for agronomic traits in rice (Oryza sativa L.)

Summary Effect of sterilizing (WA) cytoplasm on heterosis and combining ability for days to flowering, plant height and grain yield in rice was studied in 70 crosses and their reciprocals produced by 10 cytoplasmic male sterile (A), their maintainer (B) and seven restorer (R) lines following line x tester design. The materials consisting of 140 hybrids (70 A/R and their reciprocal 70 R/B) plus 17 parental lines (10 B + 7 R) were evaluated under six environments, created by growing in three fields with different fertilizer doses (0, 60, 120 kg N/ha) and 2 seasons (dry and wet) during 1986 at IRRI farm. Reciprocal cross effect (A/R vs R/B) were highly significant for all the three traits. Interaction of reciprocal cross effects with environments were also highly significant for yield and days to flowering. Cytoplasmic effect for yield, days to flowering and plant height were estimated by comparing A/R and R/B combination and testing the significance of difference with LSD value. In order to avoid confounding effect of spikelet sterility on yields, twenty crosses showing normal spikelet fertility were selected. Both positive and negative cytoplasmic effects were observed for the three traits. The effects were modified by environments, except for plant height. Heterosis for all three traits was also affected by cytoplasm, however, manifestation of cytoplasmic effects was higher for heterosis for days to flower than in heterosis for yield and plant height. Effect of cytoplasm was more pronounced on general combining ability effects of parents than specific combining ability effects of crosses. Among the parents two CMS lines A4 (IR54752A) and A8 (IR22107-113-3-3A) and two R lines: R2 (IR46) and R7 (IR9761-19-1) showed consistent positive effect of cytoplasm on general combining ability. These lines have given several good heterotic combinations. The study indicated the usefulness of evaluating diverse cytoplasmic sources in various nuclear genotypes bred for hybrid rice breeding program.     

Genetic effects and genotype × environment interactions for cooking quality traits in Indica-japonica crosses of rice (Oryza sativa L.)

Indica-japonica hybridization is an important approach for developing superior performing hybrids in rice (Oryza sativa L.). In view of the scanty information available on cooking quality characters in indica-japonica crosses, an investigation was undertaken to estimate genetic and genotype × environment variance and covariance components of amylose content, gel consistency and alkali digestion value, and to determine the relative importance of direct genetic effects, maternal genetic effects and cytoplasmic effects in the genetic variations of the three quality characters. Two indica photo-sensitive genic male sterile (PGMS) lines and four japonica varieties were used as parents to make crosses. Genetic model with genotype × environment interactions for triploid endosperm was used for genetic studies of the three cooking quality characters. Variance component analysis revealed that genetic variations of the three characters were mainly attributable to direct additive and maternal additive effects, and the three traits had significant direct and maternal heritabilities. Genotype × environment interactions were mainly dominance × environment (including direct dominance × environment and maternal dominance × environment) and cytoplasm × environment interactions. Environment factors could only affect the expression extent of dominant genes, without changing their directions. Predicted values of genetic effects indicated that the parental lines, ‘VI-70’ and ‘H9304-1’, appeared to be best for amylose content, ‘T 1950’ and ‘Suxuan’ appeared to be best for gel consistency and alkali digestion value. This revised version was published online in August 2006 with corrections to the Cover Date.     

籼稻稻米直链淀粉含量的胚、胚乳、细胞质和母体遗传效应分析

采用禾谷类作物种子数量性状遗传模型和统计分析方法, 分析了籼稻稻米直链淀粉含量的 胚、 胚乳、 细胞质和母体植株遗传效应以及环境互作效应。 结果发现稻米直链淀粉含量 的表现主要受制于基因的遗传主效应, 环境互作效应对其影响较小。 控制直链淀粉含量的 遗传主效应以胚乳效应为主, 细胞质效应和母体效应对直链淀粉含     

油菜籽硫代葡萄糖苷含量的胚、细胞质、母体遗传效应分析

采用双子叶作物种子数量性状遗传模型和统计分析方法，分析了油菜籽硫代葡萄糖苷（硫苷）含量的胚、细胞质和母体植株等不同遗传体系的基因效应以及环境互作效应。结果发现油菜籽硫苷含量的表现主要受制于母体遗传效应，其次为细胞质效应，胚（子叶）效应对其影响较小。不同遗传体系的基因主效应要明显大于环境互作效应。硫苷     

甘蓝型油菜硫苷组分的胚、细胞质和母体遗传效应分析

利用甘蓝型油菜4个显性纯合两用系与7个恢复系配制不完全双列杂交组合，采用广义种子遗传模型分析甘蓝型油菜硫苷组分的胚、细胞质和母体植株3套遗传体系的基因主效应和基因型×环境效应。结果表明硫苷组分性状受制于基因主效应，基因型×环境互作效应作用较小。2-羟-3-丁烯基、3-丁烯基以胚主效应为主，分别占75.21%和58.25%。4-羟-3-吲哚甲基、苯乙基以细胞质效应为主，分别占74.19%和69.54%。4-戊烯基由胚主效应和细胞质效应共同控制，分别占50.29%和38.12%。在基因型×环境互作方差中，4-羟-3-吲哚甲基仅受制于细胞质互作效应，其余硫苷组分均以显著的胚互作效应和细胞质互作效应为主。5个硫苷组分均以普通狭义遗传率为主，互作狭义遗传率较低。在普通狭义遗传率中，2-羟-3-丁烯基、3-丁烯基以胚遗传率为主，分别为71.61%和53.76%。4-羟-3-吲哚甲基和苯乙基以细胞质遗传率为主，分别为68.21%和68.47%。4-戊烯基以胚遗传率和细胞质遗传率为主，分别为47.81%和36.24%。在互作狭义遗传率中，5个硫苷组分以细胞质互作遗传率为主，均达到了显著水平。亲本遗传效应值预测表明，选用D3AB、D21R作为硫苷品质改良亲本有利于降低杂种后代油菜籽中2-羟-3-丁烯基和3-丁烯基的含量。     

大豆脂肪酸组分的胚、细胞质和母体遗传效应分析

利用5个大豆品种配制20个杂交组合,采用广义种子遗传模型分析了大豆脂肪酸组分的胚、细胞质和母体植株等3套遗传体系的基因主效应和基因型×环境效应。棕榈酸含量、硬脂酸含量和亚油酸含量是以基因型×环境互作效应为主。亚麻酸和油酸的遗传主效应和基因型×环境互作效应相近。在脂肪酸组分的遗传主效应中,棕榈酸、硬脂酸和亚油酸含量是以胚主效应为主。油酸含量和亚麻酸含量以细胞质主效应为主。在基因型×环境互作方差中,脂肪酸组分以极显著的胚互作方差为主。亚麻酸含量是以基因的加性效应和加性×环境互作效应为主,棕榈酸含量、硬脂酸含量、油酸含量和亚油酸含量以基因的显性和显性×环境互作效应为主。棕榈酸含量和油酸含量是以普通狭义遗传率为主。硬脂酸、亚油酸含量和亚麻酸含量以互作狭义遗传率为主。在普通狭义遗传率中,棕榈酸含量、油酸含量和亚麻酸含量以细胞质普通遗传率和母体普通遗传率为主。在互作狭义遗传率中,油酸含量和亚麻酸含量以胚互作狭义遗传率为主,亚油酸含量以母体植株互作遗传率为主。棕榈酸含量、硬脂酸含量、油酸含量和亚油酸含量以细胞质及母体选择响应和互作选择响应为主,亚麻酸含量的胚普通选择响应和互作选择响应为主。     

玉米淀粉含量的杂种优势与基因效应分析

以10个玉米自交系及按10×10完全双列杂交设计的90个F2杂交组合在两个地点的试验资料,研究玉米淀粉含量的杂种优势和基因效应。结果表明,淀粉含量表现正向的平均杂种优势,但变异幅度较小,最大值在10%左右,并在组合间、地点间存在极显著差异;淀粉含量的遗传符合加性-显性模型,不存在上位性效应。基因显性效应的作用远大     

水稻稻米Hg累积的遗传生态特性研究

选用6个不同类型的水稻品种（系）,按完全双列杂交设计（6×5）配成一套亲本、F1和F2 3个世代的遗传材料。采用包括种子、细胞质、母体植株三套遗传体系的种子性状遗传模型和统计分析方法,系统分析了稻米汞含量性状的遗传特点。主要结果如下：遗传方差分析结果表明,Hg元素含量除了受制于种子基因效应、细胞质基因效应和母体植株基因效应等遗传主效应外,还会明显受到各遗传效应与环境互作效应的影响,汞元素含量主要以遗传主效应为主。在各遗传体系中,汞元素含量以显性效应及其与环境互作效应为主,种子基因效应也有一定作用。遗传率和选择响应分析结果表明,汞总狭义遗传率较高,世代的遗传传递力较强,在鉴定筛选淘汰时,需要加大群体才能达到降低Hg元素含量的育种目标。