稻米营养品质种子效应和母体效应的遗传分析

采用谷类作物种子数量性状的遗传模型,以珍汕９７Ａ等６个籼型不育系与测早２－２等,３个早籼恢复系进行不完全双列杂交,对籼型杂交稻稻米营养品质性状进行了遗传分析。结果表明：稻米蛋白质含量和蛋白质指数主要受制于母体遗传效应,但亦受到种子基因效应的影响;赖氨酸含量和赖氨酸指数则主要与种子基因效应有关,其中赖氨酸含量还受到母体加性效应的影响。除赖氨酸指数外,其它营养品质性状的种子直接遗传率和母体遗传率均已达到极显著水平。遗传效应预测值表明,选用浙南１号Ａ和２６７１５较易获得稻米营养品质较为理想的籼型杂交稻组合。     

稻米营养品质性状的间接选择和遗传改良

利用9个籼型不育系与5个籼型恢复系按不完全双列杂交方式配制杂交组合,采用胚乳遗传模型分析籼稻碾磨和外观品质与营养品质性状间的多种遗传相关．结果表明,籼稻稻米营养品质与其它一些品质性状间存在着较强的胚乳直接加性相关、胚乳直接显性相关、细胞质相关、母体加性相关和母体显性相关．糙米重与赖氨酸指数等以正向加性相关和细胞质相关为主的成对性状,具有较好的间接选择效果．除了糙米宽与营养品质成对性状外,糙米长厚比与蛋白质含量等以负向加性相关为主、细胞质相关不明显或为负值的成对性状,将不易取得良好的同步改良效果．多数细胞质相关具有正向的较大相关系数,表明控制不同稻米品质性状表达的细胞质效应之间的相关是不可忽视的．糙米宽与蛋白质含量等以显性相关为主的成对性状则可以在杂交稻育种中加以应用．     

The dynamic gene expression from different genetic systems for protein and lysine contents of indica rice

The dynamic expression of genes for protein and lysine contents of rice grain under different environments was carried out with time-dependent measures by using the developmental genetic models for quantitative traits of triploid endosperm in cereal crops. The results showed that the genetic effects, especially genotype × environment (GE) interaction effects from the genes expression of different genetic systems including triploid endosperm, cytoplasm and diploid maternal plant were important for the performance of both nutrient quality traits at all developmental times/stages of rice grain. The conditional genetic variance analysis found that the activation of quantitative genes especially from endosperm and maternal plant genetic systems for protein and lysine contents was gradually carried through the developmental process of rice grain. The net genetic effects showed that the new expression of quantitative genes for protein and lysine contents was more active at late filling stage (15–21 days after flowering) and maturity stage (22–28 days) of rice grain. Also the sequential expression of cytoplasmic genes cannot be ignorable for the development of nutrient quality traits. The phenomena that some genes could continuously express for several developmental stages or the genes expression could be interrupted among developmental stages of rice grain was detected especially for net endosperm additive main effects or maternal additive main effects. The differences of genetic relationships from different genetic systems were found for protein and lysine contents among developmental times of rice grain.     

Genetic and heterosis analysis for cooking quality traits of indica rice in different environments

Genetic effects and genotype×environment (GE) interaction effects on the cooking quality traits of indica rice (Oryza sativa L.) were analyzed based on a genetic model for quantitative traits of triploid endosperm in cereal crops. Nine cytoplasmic male-sterile lines as females and 5 restoring lines as males were used in an incomplete diallel cross over 2 years. The cooking quality traits studied were observed to be mainly controlled by genetic effects, but GE interaction effects, especially for amylose content (AC) and alkali spreading score (ASS), were also indicated. Among the genetic effects, seed direct effects and maternal effects were the main components of AC and ASS, respectively; cytoplasmic effects were the main components of gel consistency (GC). Among the GE interaction effects, AC and ASS were mainly affected by maternal interaction effects and GC by direct interaction effects. Additive effects and/or additive interaction effects were the main factors controlling the performance of rice cooking quality traits except for GC which was affected by dominant interaction effects. For AC and GC, there were seed heterosis and/or maternal heterosis. The predicated genetic effects indicated that four parents were better than the others in improving the rice cooking quality traits of the progenies. It was shown that genetic heterosis and GE interaction heterosis were important, especially for amylose content trait in early season indica rice.     

Genetic control of paste viscosity characteristics in indica rice (Oryza sativa L.)

 Paste viscosity parameters play an important role in estimating the eating, cooking and processing quality of rice. Four cytoplasmic male-sterile (CMS) lines and eight restorer (R) lines were employed in an incomplete diallel cross to analyze seed effects, cytoplasmic effects and maternal gene effects on the viscosity profiles of indica rice. The results indicated that the viscosity profiles of rice were controlled by the direct effects of the seed, by the cytoplasm and by maternal plant. The seed-direct effects (V _A +V _D ) accounted for over 51% of the total genetic variances (V _A +V _D +V _C +V _Am +V _Dm ) for all the traits, suggesting that seed direct effects were more important than maternal effects and cytoplasmic effects. The additive variances (V _A +V _Am ) were much larger than the dominance variances (V _D +V _Dm ), which revealed that additive genetic effects were the major contributors of genetic variation for the paste viscosity profiles, and that selection could be applied for viscosity traits in the early generations. Significant cytoplasmic variance (V _C ) was detected for hot paste viscosity (HPV), cool paste viscosity (CPV) and consistency viscosity (CSV). The cytoplasmic effects for these three traits can, therefore, not be neglected in rice breeding. It was also shown that seed heritabilities (h ² _o ) tended to be larger than maternal heritabilities (h ² _m ) and cytoplasmic heritabilities (h ² _c ). Prediction of the main genetic effects for 12 parents showed that CMS lines had highly positive effects on all the traits except for the breakdown viscosity (BDV), and that R lines had both positive and negative effects on the paste viscosity characteristics. Received: 3 August 1998 / Accepted: 28 November 1998     

Cotton chromosome substitution lines crossed with cultivars: genetic model evaluation and seed trait analyses

Seed from upland cotton, Gossypium hirsutum L., provides a desirable and important nutrition profile. In this study, several seed traits (protein content, oil content, seed hull fiber content, seed index, seed volume, embryo percentage) for F₃ hybrids of 13 cotton chromosome substitution lines crossed with five elite cultivars over four environments were evaluated. Oil and protein were expressed both as percentage of total seed weight and as an index which is the grams of product/100 seeds. An additive and dominance (AD) genetic model with cytoplasmic effects was designed, assessed by simulations, and employed to analyze these seed traits. Simulated results showed that this model was sufficient for analyzing the data structure with F₃ and parents in multiple environments without replications. Significant cytoplasmic effects were detected for seed oil content, oil index, seed index, seed volume, and seed embryo percentage. Additive effects were significant for protein content, fiber content, protein index, oil index, fiber index, seed index, seed volume, and embryo percentage. Dominance effects were significant for oil content, oil index, seed index, and seed volume. Cytoplasmic and additive effects for parents and dominance effects in homozygous and heterozygous forms were predicted. Favorable genetic effects were predicted in this study and the results provided evidence that these seed traits can be genetically improved. In addition, chromosome associations with AD effects were detected and discussed in this study.     

Genetic control of the opaque-2 gene and background polygenes over some kernel traits in maize (Zea mays L.)

Some kernel traits of agronomical importance in maize are affected by the opaque-2 (o2) gene and background polygenes, which express in different genetic systems such as embryo, endosperm, cytoplasm and maternal plant. A genetic model for seed quantitative traits with the o2 gene effects and polygenic effects as well as their GE interactions was used for protein content, lysine content, oil content and kernel density in maize. The results suggested that the o2 gene was involved in the traits investigated but the effects of the o2 gene were distinctive on various traits. The effects of the o2 gene were large on lysine content and protein content while minor on oil content. There was a substantially wide quantitative variation from polygenes expressing in different genetic systems for the traits evaluated. Significant GE interactions of the o2 gene and background polygenes declared that not only the main effects but also specific expressions depending on environments were responsible for variation of the traits studied. There seemed to have strong maternal heterosis and slight embryo heterosis for kernel density.     

籼型黑米粒形性状的遗传效应及其与矿质元素含量的遗传相关性

采用禾谷类作物种子数量性状的遗传模型,分析了灿型黑米稻品种双列杂交F1和F2种子的粒重,粒长,粒宽和粒长／粒宽等粒形性状的遗传效应及其与米粒中矿质元素Fe,Zn,Mn和P含量的遗传相关性,结果表明：4种粒形性状同时受制于种子直接遗传效应,母体效应和细胞质作用影响,其中种子直接遗传效应比母体效应和细胞质效应的作用更大,且种子直接遗传效应以加性效应占主导,粒重,粒宽和粒长／粒宽的种子直接遗传率较高,杂种早代单粒选择效果较好,粒长的种子直接遗传率和母体遗传率均属中等,较高世代的杂种进行单株选择和单粒选择均有一定效果,4种粒形性状与其米粒中矿质元素Fe,Zn,Mn和P含量表现较强的种子直接加性相关,直接显性相关,细胞质相关,母体加性相关和母体显性相关,在特种稻育种实践中,可以通过粒形性的间接选择,达到改良其矿质元素含量等营养品质性状的目标。     

Genetic and genotype × environment interaction effects for the content of seven essential amino acids in<Emphasis Type="Italic">Indica</Emphasis> rice

It is necessary for rice breeders to understand the genetic basis of nutrient quality traits of rice. Essential amino acids are most important in determining the nutrient quality of rice grain and can affect the health of people who depend on rice as a staple food. In view of the paucity of genetic information available on essential amino acids inindica rice, we estimated the genetic main effects and genotype × environment (G × E) interaction effects on the content of essential amino acids. Nine cytoplasmic male sterile lines as females and five restorer lines as males were introduced in a North Carolina II design across environments. Estimates of the content of the essential amino acids valine, methionine, leucine and phenylalanine showed that they were mainly controlled by genetic main effects, while the contents of threonine, cysteine and isoleucine were mainly affected by G × E effects. In the case of genetic main effects, both cytoplasmic and maternal genetic effects were predominant for all essential amino acids, indicating that selection for improving essential amino acid content based on maternal performance would be more effective than that based on seeds. The total narrow-sense heritabilities were high and ranged from 0.72 to 0.83. Since general heritabilities for these essential amino acids (except for cysteine) were found to be much larger than G × E interaction heritability, the improvement of content of most essential amino acids under selection would be expected under various environments. Rice varieties such as Zhenan 3, Yinchao 1, T49, 26715, 102 and 1391 should be selected as optimal parents for increasing the content of most essential amino acids, while the total genetic effects from Zhexie 2, Xieqingzao, Gangchao 1, V20, Zuo 5 and Zhenshan 97 were mainly negative and these parents could decrease the contents of most essential amino acids.     

黑米中矿质元素铁、锌、锰、磷含量的遗传效应研究

采用禾谷类作物种子胚乳数量性状模型,分析黑米稻品种双列杂交Ｆ１和Ｆ２种子的Ｆｅ、Ｚｎ、Ｍｎ、Ｐ含量的遗传效应。结果表明,４种矿质元素含量同时受制于种子直接遗传效应、母体效应和细胞质作用影响。其中,Ｆｅ、Ｚｎ、Ｍｎ含量的种子直接效应比母体效应和细胞质效应的作用更大;Ｐ含量则主要受种子直接加性、母体加性和显性效应共同作用。Ｆｅ、Ｚｎ、Ｍｎ含量的种子直接遗传率较高,在杂种早代分别结合农艺性状选择单株上各     

籼稻稻米外观品质的细胞质,母体和胚乳遗传效应分析

利用浙协2号A等9个籼型不育系和T49等5个籼型恢复系进行不完全双列杂交,研究了籼稻稻米外观品质的遗传效应．结果表明,稻米外观品质性状的表现受制于胚乳、母体和细胞质三套遗传体系．糙米长、长宽比和长厚比等性状以母体遗传率为主,而糙米宽和糙米厚则以胚乳直接遗传率为主,糙米长和长宽比等性状的细胞质遗传率亦很重要．结果还发现外观品质性状间存在着较强的遗传相关,其中糙米长与糙米宽、糙米长与糙米厚、糙米宽与糙米厚、糙米宽与长宽比、糙米厚与长厚比以及糙米长宽比与长厚比性状间以胚乳直接加性和母体加性相关为主．而糙米长与长宽比、糙米长与长厚比、糙米宽与长厚比以及糙米厚与长宽比性状间则以胚乳直接显性和母体显性相关为主．就外观品质的总体情况而言,遗传效应预测值表明参试亲本以V20A、作5A和测早2-2较好,其各种遗传效应能够显著改善稻米品质性状。V20A／102和作5A／测早2-2等组合具有较好的稻米外观品质．     

Index selection on seed traits under direct, cytoplasmic and maternal effects in multiple environments

Crop seeds are important sources of protein, oil, and carbohydrates for food, animal feeds, and industrial products. Recently, much attention has been paid to quality and functional properties of crop seeds. However, seed traits possess some distinct genetic characteristics in comparison with plant traits, which increase the difficulty of genetically improving these traits. In this study, diallel analysis for seed models with genotype by environment interaction （GE） effect was applied to estimate the variance-covariance components of seed traits. Mixed linear model approaches were used to estimate the genetic covariances between pair-wise seed and plant traits. The breeding values （BV） were divided into two categories for the seed models. The first category of BV was defined as the combination of direct additive, cytoplasmic, and maternal additive effects, which should be utilized for selecting stable cultivars over multi-environments. The three genetic effects, together with their GE interaction, were included in the second category of BV for selecting special lines to be grown in specific ecosystems. Accordingly, two types of selection indices for seed traits, i.e., general selection index and interaction selection index, were developed and constructed on the first and the second category BV, respectively. These proposed selection indices can be applied to solve the difficult task of simultaneously improving multiple seed traits in various environments. Data of crop seeds with regard to four seed traits and four yield traits based on the modified diallel crosses in Upland cotton （Gossypium hirsutum L.） were used as an example for demonstrating the proposed methodology.     

Analysis of genetic effects of nuclear–cytoplasmic interaction on quantitative traits: Genetic models for seed traits of plants

Two Genetic models (an embryo model and an endosperm model) were proposed for analyzing genetic effects of nuclear genes, cytoplasmic genes, maternal genes, and nuclear–cytoplasmic interaction (NCI) as well as their genotype by environment interaction for quantitative traits of plant seed. In these models, the NCI effects were partitioned into direct additive and dominance NCI components. Mixed linear model approaches were employed for statistical analysis. For both balanced and unbalanced diallel cross designs, Monte Carlo simulations were conducted to evaluate unbiasedness and precision of estimated variance components of these models. The results showed that the proposed methods work well. Random genetic effects were predicted with an adjusted unbiased prediction method. Seed traits (protein content and oil content) of Upland cotton (Gossypium hirsutum L.) were analyzed as worked examples to demonstrate the use of the models.     

ANALYSIS OF GENETIC CORRELATIONS FOR QUALITY TRAITS IN INDICA RICE

INTRODUCTIONTherearesomekindsofcorrelatedrelationshiPsbetweenagronomytraitsIntndtcarice．Geneticandenvlronmentatcorrelat［onshavebeenanalyzedforsometraitsInrice［‘·’J．LiandYangfoundadditivecorrelationcoefficientswerefrom一0．773to0·993forsomeflowertraitsInrice［’］．Yuhavefoundthataddltlvecorrelationwasslgnlflcantforsometraitsinbarley［13］．Uptonow,partitioningthegenotyplccovarlanceoftraitsInricehasnomorethanaddltlveanddominancecovarlancecomponents．kcausethenutrl－＊＊t吕Of凡8…     

陆地棉低酚棉种子品质性状的遗传及其杂种优势利用的研究

通过配制4个隐性无腺体品系（gl2gl2gl3gl3)作母本与5个显性无腺体品系（GL2^eGl2^3eGl3Gl3)杂交产生的20个组合的F2、F3,利用二倍体种子遗传模型,研究了棉花种子的含油量、蛋白质含量、油分指数、蛋白质指数等5个种子性状的遗传变异。结果表明所有研究的性状主要由加性遗传效应所控制,其中含油量主要由母体加性遗传效应所控。按群体平均数计算。这些性状F2的中亲优势仅为－1．99％－1．11％,这揭示出F2、F3近交衰退很少。有75％的F2和60％的F3天然授粉异交组合棉酚含量低于0．4g/kg,因此有可能筛选出棉酚含量低于规定标准、而种子品质不降低、可综合利用的F2高产杂交种。     

Genetic analysis of amino acid content in wheat grain

Complete diallel crosses with five parents of common wheat (Triticum aestivum L.) were conducted to analyse inheritance of 17 amino acid contents by using the genetic model including seed, cytoplasmic, maternal and environment interaction effects on quantitative traits of seeds in cereal crops. The results showed that inheritance of 17 amino acid contents, except tyrosine, was controlled by several genetic systems including seed, cytoplasmic, and maternal effects, and by significant gene × environment interaction effects. Seed-direct additive and maternal effects constituted a major part of genetic effects for lysine, tyrosine, arginine, methionine, and glutamic acid content. Seed-direct additive effect formed main part in inheritance of isoleucine and serine contents. Threonine content was mainly governed by maternal additive effect. The other nine amino acid contents were almost entirely controlled by dominance effects. High general heritability of tyrosine (36.3%), arginine (45.8%), lysine (24.7%) and threonine (21.4%) contents, revealed that it could be effective to improve them by direct selection in progenies from appropriate crosses. Interaction heritability for phenylalanine, proline, and histidine content, which was 36.1%, 39.5% and 25.7%, respectively, was higher than for the other amino acids.     

Variation in seed and seedling traits in Pithecellobium pedicellare,a tropical rain forest tree

Summary Pithecellobium pedicellare, a mimosoid legume, is a large canopy tree in the tropical rain forests of Costa Rica. We examined the pattern of variation in seed weight, germination date, hypocotyl length (stem), and rachis length (the first leaf) of the seedlings in this species. Seeds collected from widely dispersed individual trees at the La Selva Biological Station, Costa Rica, were randomly planted in blocks, and grown under controlled, indoor conditions for about 2 weeks. There-fore, we were able to quantify the effects of maternal family on mean seed weight and the effects of maternal family and microenvironment on the remaining traits examined. A significant effect of maternal family was detected for all traits. In particular, the maternal effects on germination date and seedling size traits which were consistently significant even after controlling the initial seed weight may indicate that the maternal effects reflect, at least to some extent, maternal genetic control over these traits. Despite overall strong maternal effects, the performance of maternal siblings, such as the rachis length, differed among blocks. The sensitivity of maternal siblings to the local environments may contribute to the maintenance of genetic variability in this highly outcrossing tropical species.     

籼稻稻米蛋白质含量与外观品质性状间不同遗传体系的条件遗传相关分析

选用稻米蛋白质含量等品质差异较大的7个籼型不育系(A)及相应的保持系(B)与5个籼型恢复系(R)杂交,组成7×5不完全双列杂交组合。应用包括胚乳、细胞质和母体植株基因的遗传主效应以及基因型×环境互作效应的数量性状遗传模型及非条件和条件分析方法,研究了籼稻稻米蛋白质含量与外观品质性状间的遗传相关性,进一步揭示了籼稻糙米重、稻米直链淀粉含量对稻米蛋白质含量与外观品质性状间遗传相关性的影响。非条件分析的结果表明,除了与糙米厚的相关性未达到显著水平以外,蛋白质含量与其它稻米外观品质性状间的遗传相关性均达极显著水平,其中与糙米宽间的相关性表现为正值,其余为负向相关。条件分析的结果显示,糙米重和直链淀粉含量对稻米蛋白质含量与外观品质性状间的遗传相关性均可产生较大的影响。糙米重主要通过基因型×环境互作效应影响蛋白质含量与外观品质性状间的遗传相关性,其中对蛋白质含量与糙米长、糙米宽、糙米厚间遗传相关性的影响主要表现为负向作用,而对蛋白质含量与糙米长宽比、糙米长厚比间遗传相关性的影响则表现为正向作用。稻米直链淀粉主要通过细胞质遗传主效应和母体加性效应影响蛋白质含量与糙米长、糙米长宽比、糙米长厚比间的遗传相关性,而对蛋白质含量与糙米宽间的相关性影响主要表现为负向作用。     

PATERNAL CARE: DIRECT AND INDIRECT GENETIC EFFECTS OF FATHERS ON OFFSPRING PERFORMANCE

Knowledge of how genetic effects arising from parental care influence the evolution of offspring traits comes almost exclusively from studies of maternal care. However, males provide care in some taxa, and often this care differs from females in quality or quantity. If variation in paternal care is genetically based then, like maternal care and maternal effects, paternal effects may have important consequences for the evolution of offspring traits via indirect genetic effects (IGEs). IGEs and direct–indirect genetic covariances associated with parental care can contribute substantially to total heritability and influence predictions about how traits respond to selection. It is unknown, however, if the magnitude and sign of parental effects arising from fathers are the same as those arising from mothers. We used a reciprocal cross‐fostering experiment to quantify environmental and genetic effects of paternal care on offspring performance in the burying beetle, Nicrophorus vespilloides. We found that IGEs were substantial and direct–indirect genetic covariances were negative. Combined, these patterns led to low total heritabilities for offspring performance traits. Thus, under paternal care, offspring performance traits are unlikely to evolve in response to selection, and variation in these traits will be maintained in the population despite potentially strong selection on these traits. These patterns are similar to those generated by maternal care, indicating that the genetic effects of care on offspring performance are independent of the caregiver's sex.     

Analysis of the genetic behavior of some starch properties in indica rice ( Oryza sativa L.): thermal properties,gel texture,swelling volume

Starch comprises about 90% of milled rice, so that the eating and cooking quality of rice is mainly affected by the starch properties. In the present paper, we analyzed the genetical behavior of gelatinization temperature tested by differential scanning calorimetry (DSC), gel texture, and the swelling volume (SV) of indica rice with an incomplete cross of 4×8 parents. A genetic model which can dissect the effects of triploid seed, the cytoplasm, and the maternal plant on the endosperm traits was used. The results indicated that peak temperature (T_p), conclusion temperature (T_c) and enthalpy (ΔH) were controlled by three types of genetic effects: seed direct (endosperm) effects, cytoplasmic effects and maternal effects. No cytoplasmic effects for the onset temperature (T_o), hardness and SV, and no maternal effects for cohesiveness were found. The additive variances (V _A +V _Am ) were larger than the dominance variances (V _D +V _Dm ) for all the traits except for T_c, which suggested that selection could be applied for the starch properties in early generations. The total narrow-sense heritability for each parameter was over 60%, indicating that selection advances were predictable in the early generations for these traits. Received: 17 February 2001 / Accepted: 17 May 2001