Genetic control of fatty acid composition in seed oil of Sinapis alba L.

Summary Inheritance of fatty acid composition was studied in an F1 diallel cross in Sinapis alba. Crosses were made among accessions having contrasting amounts of oleic (C18:1) and erucic (C22:1) acid. Concentrations of oleic, linoleic (C18:2), eicosenoic (C20:1) and erucic (C22:1) acids were determined by gas-chromatography for each mating combination. Genetic analysis confirmed that the composition of the fatty acids was controlled mainly by the nuclear genes of the embryo. Additive gene action with partial dominance for the reducing alleles was noted for oleic and linoleic acids, while erucic acid showed an additive mode of inheritance with partial dominance for the enhancing alleles. Positive heterosis was demonstrated for eicosenoic acid content. Erucic acid content was strongly negatively correlated with oleic acid, suggesting a genetic interdependence between the two fatty acids. Broad-sense and narrow-sense heritability estimates for each of oleic, linoleic and erucic acids were very high, due to low between-plants non-genetic component of variance.Contribution No. 3662-E, 1992 series.     

Estimating the fatty acid composition of the oil in intact-seed rapeseed (Brassica napus L.) by near-infrared reflectance spectroscopy

The objective of this work was to evaluate the potential of near-infrared reflectance spectroscopy (NIRS) as a rapid method to estimate the fatty acid composition of the oil in intact-seed samples of rapeseed. A total of 549 samples (3 g intact seed) from selected mutant and breeding lines were scanned by NIRS, and 220 of them were selected and scanned again by using two different adapters, which reduced the sample size to 300 and 60 mg, respectively. Selected samples were analysed by gas liquid chromatography and calibration equations for individual fatty acids were developed. Calibrations for oleic, linoleic, linolenic, and erucic acid were highly accurate, with values of r² in cross validation from 0.95 to 0.98 (samples of 3 g), from 0.93 to 0.97 (300 mg), and from 0.84 to 0.96 (60 mg). Calibrations for palmitic and stearic acid were less accurate, with values of r² in cross validation always lower than 0.8, probably because of the narrow range available for these fatty acids. The accuracy of the calibration equations for eicosenoic acid was very low (r² = 0.69 in 3 g samples), although improved equations were developed (r² from 0.78 to 0.91) when the relationship between erucic and eicosenoic acid was taken into account. We conclude that NIRS is a powerful technique to estimate the fatty acid composition of the oil in rapeseed, provided that samples covering a wide range of fatty acid levels are available, with the advantage that such estimation is possible with few additional costs when NIRS is used for the determination of other seed quality traits. This revised version was published online in July 2006 with corrections to the Cover Date.     

甘蓝型油菜种子中几种主要脂肪酸含量的遗传

通过对甘蓝型油菜杂交组合(华油8号×Altex)正反交 F_1、F_2、回交一代以及相应的杂交亲本种子中几种主要脂肪酸含量的气相色谱测定,研究了芥酸、廿碳烯酸、油酸、亚油酸和亚麻酸含量的遗传以及这几种脂肪酸之间的相互关系。研究结果表明:种子中的芥酸、廿碳烯酸和油酸含量都是由胚基因型决定的,这三种脂肪酸含量受到一个共同     

Increasing erucic acid content in Ethiopian mustard through mutation breeding

Ethylmethane sulphonate (EMS) was applied to seeds of the Ethiopian mustard (Brassica carinata A. Braun) line C-101. Bulk samples of M₃ seeds from 8331 M₂ plants were evaluated for the fatty acid composition of their oil by near-infrared reflectance spectroscopy (NIRS) and by further gas chromatography on selected samples. A putative mutant, N2-6230, showing very low oleic acid content (4.7% vs. average of 8.6% in C-101) and erucic acid content within the range of variation of the line C-101 (40-49.3%) was identified. The M₃ progeny of this mutant showed a wide segregation for erucic acid content (39.1-57.9% vs. 41.8-50.3% in C-101), and maintained levels of oleic acid lower than in line C-101. Selection for high erucic acid content in the M₃ and M₄ generations led to the fixation of this mutation in the M₅ generation (52.2-59.3% vs. 39.0-47.6% in C-101). This is the first high erucic acid line obtained in Brassica species through mutation breeding. Its utility in future programmes to develop very high erucic acid lines is discussed.     

Genetics of the Erucic Acid Content in Interspecific Hybrids of Ethiopian Mustard (Brassies carinata Braun) and Rapeseed (B. napus L.)

Ethiopian mustard (Brassica carinata Braun) is a potential oil crop in which genes for low erucic acid content of the seed oil have not yet been found. In order to solve this problem the potential of rapeseed (B. napus L.) varieties as a source of these genes has been tested. Reciprocal F₁ hybrids between B. carinata and a low erucic acid variety of B. napus, F₂, and backcrosses with B. carinata were obtained. The fatty acid composition was determined in half seeds of F₁ and segregating generations from reciprocal interspecific crosses. The genetic analysis indicated that the erucic acid content of the seed oil of B. carinata is controlled by two genes with no dominance and additive in action.     

Fatty Acid Composition of Oil from Erucic Acid-Free Summer Rape Seed (Brassica napus L.) in Relation to Nitrogen Nutrition and Raceme Position

A greenhouse study was conducted to determine the effect of nitrogen supply (30, 100 or 170 ppm N) and raceme position on the fatty acid composition of oil extracted from erucic acid-free summer rape seed ( Brassica napus cv. Callypso ). The seven fatty acids analyzed for include palmitic, palmitolcic, stearic, oleic, linoleic, linolemc, and eicosenoic acids; of which oleic (59.54–64.84 %) and palmitoleic (0.36–0.4 %) acids were the highest and lowest levels respectively. Generally, N nutrition influenced fatty acid pattern only to a little extent. Palmitic, palmitoleic and stearic acid levels were increased by 170 ppm N, depending on raceme position, but oleic and linolenic acids were unaffected. Similarly, 170 ppm N produced the highest fatty acid levels in seeds on the lower portions of racemes, with the exception of oleic acid. This was also true in the case of the upper portions of racemes, except that 30 ppm N produced the highest levels of oleic and linoleic acids in rape seeds. Under the optimum N supply level (i.e. 100 ppm N), position of raceme on the rape plant did not greatly influence the levels of different fatty acids in lipids.     

Impacts of erucic acid and glucosinolate content on genetic relationships between protein content and fatty acids of rape seed across environments

Impacts of erucic acid content (EAC) and glucosinolate content (GSLC) on the genetic correlations between protein content (PC) and oil content (OC) or PC and fatty acid contents (FAC) in rape seed (Brassica napus L.) was analyzed by using unconditional and conditional methods related to genetic effects from the diploid embryo nuclear genes, cytoplasm genes and diploid maternal plant nuclear genes. A diallel mating design in two environments was conducted by using eight varieties along with their F₁ and F₂. It was found that there were significant relationships between PC and EAC or PC and GSLC of rape seed, and the conditional analysis method could be used to exclude the influences of EAC or GSLC for further revealing the actual genetic relationships between PC and OC or PC and FAC. The results from conditional analysis showed that when PC was conditioned on EAC or GSLC the conditional phenotypic and genotypic relationships between PC|EAC and oleic acid content or PC|GSLC and OC were changed to significantly positive, while those between PC|EAC and eicosenoic acid content or PC|GSLC and linolenic acid content became significantly negative. Thus, the levels of EAC and GSLC of rape seed could affect the correlations between PC and OC or PC and FAC. For the conditional genetic relationship analysis of different genetic systems, visible changes were found for many genetic correlation components from the embryo, cytoplasm and maternal plant between PC and OC or PC and FAC after eliminating the influences of EAC or GSLC, especially for conditional embryo dominance, cytoplasmic, maternal additive main covariances and conditional embryo dominance interaction covariance.     

Analysis of the genetic control of β-carotene and <Emphasis Type="SmallCaps">l</Emphasis>-ascorbic acid accumulation in an orange-brownish wild cherry tomato accession

An additive-dominance, additive × additive (ADAA) and genotype × environment interaction mix model was used to study the genetic control of β-carotene and l-ascorbic acid in six basic generations (P₁, P₂, F₁, F₂, BC₁P₁ and BC₁P₂) of tomato derived from the cross CDP8779 accession (Solanum lycopersicum L.) × CDP4777 accession (S. lycopersicum var. cerasiforme). The study was performed in two environments: (1) open field; (2) protected environment, consisting of hydroponic cultivation in a glasshouse. The results indicate that β-carotene accumulation was mainly additive (32.2% of the genetic component), with a small dominant component (4.2%) and an important additive × environment interaction contribution (63.6%). In target environments with moderate to high temperatures and no limiting radiation, this the expression additive × environment interaction could substantially enhance the β-carotene content. This trait showed also a high narrow-sense heritability (h ² = 0.62). Ascorbic acid accumulation was also mainly additive (61.7% of the genetic component), with a minor additive epistatic component (21.5%). This epistatic effect caused a negative heterosis that reduced the positive main additive effect. Nevertheless, in the described target environments, the additive × environment interaction contribution (16.8%) may enhance the ascorbic acid content and compensate for the negative heterosis effect. The total narrow-sense heritability of this trait can be considered useful (h ² = 0.52). In conclusion, the CDP4777 accession is a very interesting donor parent for the joint improvement of β-carotene (without diminishing lycopene content) and ascorbic acid content in commercial nutraceutical tomato breeding programmes; the F₁ hybrids derived from this accession showed nearly 450% of the commonly reported average β-carotene content and close to 130% of the ascorbic acid content of the female parent.     

甘蓝型油菜主要脂肪酸组成的QTL定位

应用RAPD、SSR和SRAP技术, 对甘蓝型油菜低芥酸品系APL01与高芥酸品系M083杂交组合的BC1F1群体进行检测, 获得251个分子标记, 构建了19个连锁群组成的分子标记遗传图谱; 应用WinQTLCart 2.0对油菜主要脂肪酸组成进行QTL扫描, 获得与棕榈酸含量相关的QTL 5个, 分别位于N3、N8、N10和N13连锁群, 其中效应值较大的主效QTL qPA8-1和qPA13分别可解释棕榈酸含量表型变异的11.31%和14.47%。获得与硬脂酸含量相关的QTL 3个, 分别位于N1、N8和N16连锁群, 其中效应值较大的主效QTL qST16可解释硬脂酸含量表型变异的12.22%。获得与油酸含量相关的QTL 2个, 位于N8和N13连锁群, 均为主效QTL, 其中qOL8位于N8连锁群的m11e37b~A0226Ba267区间, 可解释油酸含量表型变异的11.73%, qOL13位于N13连锁群的m18e46~m20e25a区间, 可解释表型变异的27.14%。获得与亚油酸含量相关的QTL 3个, 其中主效QTL qLI8-1位于N8连锁群, 可解释亚油酸含量表型变异的13.25%。获得与亚麻酸含量相关的QTL 3个, 效应值均较小, 属微效QTL。获得与廿碳烯酸含量相关的QTL 4个, 分别位于N8、N13和N15连锁群, 其中主效QTL qEI8-1、qEI8-2和qEI13分别可解释廿碳烯酸含量表型变异的12.20%、10.22%和11.14%。获得与芥酸含量相关的QTL 2个, 位于N8和N13连锁群, 均为主效QTL, 其中qER8位于N8连锁群的m11e37b~A0226Ba267区间, 可解释芥酸含量表型变异的16.74%; qER13位于N13连锁群的A0301Bb398~m18e46区间, 可解释芥酸含量表型变异的31.32%。在N8连锁群的分子标记m11e27b附近及N13连锁群的分子标记m18e46附近存在多个主要脂肪酸的主效QTL, 这些标记可用于油菜脂肪酸改良的分子标记辅助选择。     

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。     

工业专用型高芥酸油菜新品种选育

高芥酸油菜品种是在工业上具有广泛用途的专用型品种。本研究通过两个常规芥酸品种杂交,采用以单株和单粒筛选相结合对芥酸含量正向选择为核心的技术,育成了芥酸含量达60%的甘蓝型高芥酸油菜新品种高芥1号。同时阐明了在高芥酸含量背景下各种脂肪酸间的相关性,为相关育种提供了—些理论依据。     

Allelic variation in linolenic acid content of high erucic acid Ethiopian mustard and incorporation of the low linolenic acid trait into zero erucic acid germplasm

Zero erucic acid germplasm of Ethiopian mustard is characterized by high levels of linolenic acid (about 21%). Two genetic sources of low linolenic acid (N2‐4961 and HF‐186, about 5%), have been developed in a high erucic acid background. The objectives of this research were to study the genetic relationship between the two low linolenic acid lines and to transfer the trait to zero erucic acid germplasm. F1 seed generations from crosses between both lines had higher average linolenic acid concentration than both parents. F2 seeds segregated for linolenic acid content following a continuous variation from 1.8 to 7.4%, exceeding the limits of the parental distribution ranges. Transgressive recombinants with very low linolenic acid concentration (0.7‐2.7%) were confirmed in the F3 seed generation. The results suggested that N2‐4961 and HF‐186 possess alleles for low linolenic acid at different loci. Transgressive low linolenic acid F3 plants were crossed with plants of a zero erucic acid line and a selection for zero erucic, low linolenic acid was conducted. As a result, a zero erucic acid F3:4 line containing 1.5 ± 0.7% linolenic acid was developed.     

Effects of minimal temperatures on low-linolenic rapeseed oil fatty-acid composition

Rapeseed oil is rich in alpha-linolenic acid (C18:3) and has a low content in saturated fatty acids. It is therefore considered as a very healthy edible oil. However, its high polyunsaturated fatty acid content makes it sensitive to temperature oxidation and therefore not suitable for deep-frying. Low-linolenic varieties with C18:3 content lower than 3.5% have been bred, but a large variability of alpha-linolenic acid content has been often observed in agricultural production of these new lines. Identifying factors affecting the fatty acid profile of oilseed rape should make it possible to produce rapeseed with alpha-linolenic acid content lower than 2.5% and therefore more suitable for frying and other uses in the food industry.Fatty acid composition is affected by environmental conditions, temperature being the main factor. Previous works showed that for conventional double-low rapeseed varieties, low minimal temperatures during the 60 days following the onset of flowering were related to higher alpha-linolenic acid contents.Monitoring the fatty acid profile in low-linolenic varieties from the beginning of seed filling to full maturity showed that alpha-linolenic acid synthesis occurred mainly between 550 and 850 degree-days (base 0 °C) after the onset of flowering, that is during the 20 first days of seed filling in Swiss conditions, i.e. 41–60 days after the onset of flowering. During this period, the determination coefficient of a second order regression between final alpha-linolenic acid (C18:3) content and minimal daily temperature was even better, with R² = 0.87. A significant positive relation was also found for the regression between minimal temperature and oleic acid (C18:1) content for the cultivar Splendor (R² = 0.77) but no correlation could evidence a relation between temperature and linoleic acid (C18:2) content.An easier way to show the relationship between linolenic acid content and minimal temperatures is based on the assumption that fatty acid desaturases regulated by temperature are active at low temperatures only. It consists in counting how many times during this period daily minimal temperature reaches a minimal threshold temperature of 13 °C. The relationship between final alpha-linolenic acid content and the number of days with minimal temperature below 13 °C is as good as the one presented before, i.e. with a determination coefficient, R² = 0.85. This simple model could be used to determine the growing areas with low linolenic acid content.     

Genetic structure composed of additive QTL,epistatic QTL pairs and collective unmapped minor QTL conferring oil content and fatty acid components of soybeans

The relative importance of various types of quantitative trait locus (QTL) conferring oil content and its fatty acid components in soybean seeds was assessed through testing a recombinant inbred line (RIL) population (derived from KF1 × NN1138-2) in randomized blocks experiments in 2004–2006. The contents of oil and oleic, linoleic, linolenic, palmitic and stearic acids were determined with automatic Soxhlet extraction system and gas chromatography, respectively. Based on the established genetic linkage map with 834 markers, QTLNetwork2.0 was used to detect QTL under the genetic model composed of additive, additive × additive (epistasis), additive × year and epistasis × year effects. The contributions to the phenotypic variances of additive QTL and epistatic QTL pairs were 15.7% (3 QTL) and 10.8% (2 pairs) for oil content, 10.4% (3 QTL) and 10.3% (3 pairs) for oleic acid, 11.6% (3 QTL) and 8.5% (2 pairs) for linoleic acid, 28.5% (7 QTL) and 7.6% (3 pairs) for linolenic acid, 27.0% (6 QTL) and 16.6% (7 pairs) for palmitic acid and 29.7% (5 QTL) and 4.3% (1 pair) for stearic acid, respectively. Those of additive QTL by year interaction were small and no epistatic QTL pair by year interaction was found. Among the 27 additive QTL and 36 epistatic QTL (18 pairs), three are duplicated between the two QTL types. A large difference was found between the genotypic variance among RILs and the total variance of mapped QTL, which accounted for 52.9–74.8% of the genotypic variation, much larger than those of additive QTL and epistatic QTL pairs. This part of variance was recognized as that due to a collection of unmapped minor QTL, like polygenes in biometrical genetics, and was designated as collective unmapped minor QTL. The results challenge the breeders for how to pyramid different types of QTL. In addition, the present study supports the mapping strategy of a full model scanning followed by verification with other procedures corresponding to the first results.     

A comparison of traditional and haploid-derived breeding populations of oilseed rape (Brassica napus L.) for fatty acid composition of the seed oil

Summary Microspore embryogenesis technology allows plant breeders to efficiently generate homozygous micros-pore-derived breeding populations of oilseed rape (Brassica napus L.) without traditional generations of inbreeding. This study was conducted to compare the frequency distribution of microspore-derived population and single seed descent populations with respect to fatty acids of seed oil. Both microspore-derived populations and single seed descent populations were produced from each of three crosses made between selected parents containing contrasting amount of erucic, oleic, linoleic and linolenic acids. The fatty acid content of F₃ plants derived lines (F₅ seed) developed by single seed descent was compared to that of microspore-derived populations. The means, ranges and distribution pattern of seed fatty acid contents were similar in both populations for each fatty acid studied, although a few heterozygous lines were observed in the single seed descent populations. The results indicated that microspore-derived population form random, homozygous F₁ plant derived gametic arrays for all fatty acids evaluated. Selection for altered fatty acid composition in microspore-derived and single seed descent homozygous populations should be equally efficient, in the absence of linkage of traits investigated.     

Variation and inheritance of erucic acid content in Brassica carinata germplasm collections from Ethiopia

Ethiopian mustard possesses a number of agronomic advantages over other oilseed crops with similar ecological adaptation in Ethiopia. However, its high erucic acid content is undesirable for a vegetable oil. Although efforts have been made to improve its quality, much has to be done to use natural variations that might exist within the species for fatty acid contents. This project was undertaken to study the variability of fatty acid contents, primarily erucic acid, in germplasm collections of Ethiopian origin, with an attempt to develop low (zero) erucic acid genotypes. The study used inbred lines as well as F₂ populations of 10 crosses between six parental lines. A wide variation in fatty acids was found. Oleic acid content varied from 5 to 34% and erucic acid content from 6 to 51%. Linoleic and linolenic acid contents were less variable. The high‐oleic genotypes exhibited not only low erucic but also higher linoleic (25%) and considerably lower linolenic acid (8%) contents. It was possible to classify the F₂ populations with the lowest erucic acid into three distinct classes. While the first class had an erucic acid content of 6–12%, the second and third classes had contents of 18–32% and 36–42%, respectively. The existence of a multiple allelic series of erucic acid in Ethiopian mustard would enable its fixation at zero levels without necessarily going into interspecific crossing.     

Erucic acid heredity in Brassica juncea - some additional information

Genetic studies were undertaken to reassess erucic acid heredity in Brassica juncea. Analysis of segregation in F₂ and BC₁ generations from two zero × high erucic acid crosses indicated that higher erucic acid in B. juncea was controlled by two dominant genes with additive effects, whereas segregation in a cross involving ‘CCWF 16′, a genotype having intermediate erucic acid (25.6%), and a zero erucic acid strain, indicated monogenic dominant control for intermediate erucic acid content. The B. juncea strain ‘CCWF 16’ was developed by hybridizing high‐erucic acid B. juncea cv.‘WF‐1’ with a ‘0’ erucic B. rapa cv.‘Candle’ followed by backcrossing with ‘WF‐1’ and half‐seed selection for low erucic acid in each backcross generation. This strategy resulted in substitution of the high erucic acid allele present in the A genome of B. juncea (AABB) by the zero erucic acid allele associated with ‘A’ genome of ‘Candle’. The intermediate erucic acid content in ‘CCWF 16’ was thus attributed to a gene present in the ‘BB’ genome. Experimental data clearly suggested that the gene (E₂) associated with the A genome had a greater contribution to the total erucic acid content in B. juncea than the gene (E₁) located on the B genome. This provided experimental evidence for a previous suggestion of unequal contributions of two dominant genes (E₁= 12%, E₂= 20%) to high erucic acid content in conventional digenomic Brassica species.     

芥菜型油菜重组自交系群体重要品质性状的遗传分析

本研究调查了一个包含139个芥菜型油菜重组自交系群体的脂肪酸(硬脂酸、油酸、亚油酸、亚麻酸、芥酸)和硫甙含量,相关性分析显示,芥酸与其它脂肪酸间均呈极显著负相关,而除芥酸外的其它脂肪酸间则呈极显著正相关.品质性状均表现出较高广义遗传力,其中芥酸和硫甙的遗传力超过90％,硬脂酸和亚油酸的遗传力在80％～90％之间,而亚油酸和亚麻酸的遗传力在70％～80％之间.主成分分析获得2个分别能解释64.9％和16.4％的变异因子,散点图将全部139个株系分成群Ⅰ、群Ⅱ和4个散落的株系,聚类分析对于此群体品质性状的遗传和特异材料的筛选有一定参考价值.     

Effect of genetic background on the target fatty acids of acyl-ACP thioesterase transgenes in Brassica napus

Acyl‐acyl carrier protein (ACP) thioesterase (TE) is involved in the biosynthetic fatty acid pathway of plants. Conventional canola lines transformed individually with the bay‐TE (Uc FatB1), elm‐TE (Ua FatB1), nutmeg‐TE (Mf FatB1) or Cuphea‐TE transgene (Ch FatB1), produce seed oil with modified fatty acid compositions. This study assessed the effects of genetic background, cytoplasm, maternal parent, and interaction of different TE transgenes, on the target fatty acids using F1 seeds and double haploid (DH) lines. The F₁ seeds were produced by crossing four TE transgenic parental lines and three non‐transgenic cultivars with distinct fatty acid compositions. The DH lines were developed from microspores of F₁ plants. DH lines from different crosses showed that genetic background does not have an effect on the relative levels of the target fatty acids of the same TE, indicating the stability of the substrate specificity of the TE within canola. However, significant effects of genetic background on the content of the major target fatty acids, lauric acid (C12:0) or palmitic acid (C16:0) depending on the TE, were observed. Expression of the TE in low erucic acid (C22:1) genotypes resulted in higher target fatty acid levels than expression in high C22:1 genotypes. Reciprocal crosses showed maternal effects, but not cytoplasmic effects. In addition, co‐expression of two different TE transgenes in the same seeds was observed. These results indicate the importance of selection for appropriate genetic backgrounds in order to maximize the expression of the target fatty acids of TE transgenes, and also indicate potential uses of TE co‐expression in modifying canola seed oil.     

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。