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1.
Safflower (Carthamus tinctorius L.) seeds contain a high proportion of tocopherols (>90 %) in the α-tocopherol form. A mutant with a high concentration of γ-tocopherol (>85 %) was identified in germplasm of wild safflower (Carthamus oxyacanthus M. Bieb.) that showed strong introgression of C. tinctorius, which allowed selection of individuals of both species with high concentrations of either α- or γ-tocopherol. The trait is controlled by a γ-tocopherol methyltransferase (γ-TMT) locus. The objective of this research was to identify γ-TMT sequence mutations associated with the high γ-tocopherol trait. Full length genomic and cDNA sequences of the γ-TMT gene were obtained from plants of C. tinctorius and C. oxyacanthus with both tocopherol profiles. Sequences from high γ-tocopherol plants showed an 11 bp deletion in exon 6 of the γ-TMT gene that disrupted the reading frame and created a premature stop codon, resulting in a predicted protein with a drastically altered amino acid sequence downstream the frameshift site. The data suggested that the frameshift mutation was underlying the γ-TMT loss of function mutant allele that determines the high γ-tocopherol phenotype. The characterized sequence change of 11 bp deletion could be used directly as a functional marker for introgression of the high γ-tocopherol trait into elite safflower cultivars.  相似文献   

2.
Sesame (Sesamum indicum L.) is one of the most important ancient oilseed crops grown throughout the tropical and subtropical regions of the world. In Uganda, most of the cultivated sesame varieties are local landraces which are frequently traded between farmers. Although these traditional landraces are an important source of genetic diversity, knowledge of their genetic diversity is still limited.Agromorphological traits and a set of published and newly developed microsatellite markers were analyzed on a collection of 121 accessions of Ugandan sesame landraces. CpSSR analysis revealed four haplotypes, whereby haplotype B was present in 96% of the individuals. The analysis of nSSR markers from 6 non-coding regions revealed a mean PIC value of 0.56 whereas the PIC value of eight selected EST-derived SSRs was 0.26. Accession-wise, the expected heterozygosity (He) varied from 0 to 0.396. AMOVA revealed that the majority of the variance occurred among the individuals accounting for 75% of the total variation, only 6% was attributed to differences among the districts, pointing towards a high gene flow (Nm = 4.476). These results are supported by the PCoA analysis as well as the NJ tree both of which revealed no clustering of the accessions according to their geographic origin. Also the statistical analysis of 10 agromorphological traits indicated no clear pattern related to the geographic origin. Such a poor grouping, indicative of considerable gene flow across geographic domains, could be explained either by a high outcrossing rate, and/or through extensive seed trading.  相似文献   

3.
芝麻素和芝麻林素在芝麻种子萌发阶段变化规律的研究   总被引：1，自引：0，他引：1  
为了明确芝麻种子发芽过程中芝麻素、芝麻林素、水分和干物质量的变化规律,以2个芝麻种质KUUS709和YZH11为材料,研究芝麻种子在21℃发芽条件下芝麻素、芝麻林素、水分和干物质量的变化规律。结果表明,在芝麻种子发芽前期、中期和后期,芝麻素含量和芝麻林素含量呈现出“慢—快”的降解规律,芝麻素和芝麻林素含量变化的转折点在萌发36 h和48 h;水分含量和干物质量呈“S”型曲线,符合“慢—快—慢”的增长规律,其中水分变化的转折点是在萌发24 h和84 h,干物质积累量变化的转折点在萌发36 h和96 h。在芝麻种子发芽过程中,水分与干物质量呈显著正相关,芝麻素含量与芝麻林素含量呈显著正相关;水分、干物质量与芝麻素含量、芝麻林素含量呈显著负相关。本研究将为进一步探讨芝麻素和芝麻林素在种子发芽过程的生理机制奠定基础。  相似文献   

4.
A total of 16,619 ESTs sequences (SSRs) of sesame (Sesamum indicum L.) were mined from Genbank. From sequences, 156 primer pairs were designed and characterized to determine the diversity among 49 sesame accessions. Twenty SSRs were found to be polymorphic and the number of alleles ranged from two to five per locus. The allele size varied from 101 to 399 bp. The average PIC value of the 20 SSR loci was 0.72 ranging from 0.49 (SEM-12-68) to 0.90 (SEM-12-27). Dendrogram analysis grouped the 49 genotypes into five separate clusters exhibiting a genetic similarity coefficient from 0.59 to 1.0. Hence, these EST-derived SSRs markers could be useful in assessing the diversity of sesame accessions and could also help in identifying diverse parents for sesame improvement programs.  相似文献   

5.
The present study was conducted with the main objective to optimize petal yield from important marigold cultivars in West Bengal, and to standardize isolation of lutein from petals because these dietary xanthophylls are known to reduce the risks of agerelated macular degeneration (AMD) and cataracts. Six cultivars were studied viz. African marigold-Double (AFM-D), African marigold-Single (AFM-S), African marigold-Orange (AFM-O), French marigold-Orange (FRM-O), French marigold-Double (FRMD), and LC (Local type), which withstand typical environmental conditions of northern West Bengal and produce flowers that do not vary in color and are relatively unaffected by pests and diseases. Lutein esters were extracted from milled marigold petals using nhexane. However, overall performance showed that LC is superior to the other cultivars. Pure lutein was obtained after saponification with 50% KOH. The re-crystallized lutein was characterized by UV-VIS, IR spectroscopy, and HPLC. A free-flowing lutein ester was also formulated. This free-flowing lutein ester was found to be suitable to undergo commercialization or subsequent processing. An economic method for petal yield and isolation of lutein was thus standardized.  相似文献   

6.
Sesame (Sesamum indicum L.) is an important edible oil crop. Meteorological factors such as temperature, rainfall, and the amount of solar radiation determine the yield potential of sesame. To identify phenotypic diversity and to infer genotypic backgrounds in a collection of 250 sesame germplasm accessions, we classified the germplasm based on variation in morphological traits using principal component (PC) and cluster analysis. The sesame germplasm was grouped based on five PCs, which accounted for 82.3% of total variation. The first PC (PC1) was positively correlated with days to flowering, days to maturity, and number of capsules per plant, whereas the second PC (PC2) was negatively correlated with all characteristics except capsule-bearing stem length. The third component (PC3) was highly positively correlated with capsule length and plant height. We constructed a scatter diagram of the first two PCs (PC1 vs. PC2), revealing four distinct groups of eigenvectors. Most sesame germplasm was widely distributed among Groups I, II, III, and IV. Group III showed a wide range of distribution in the diagram. Otherwise, the distribution of the 250 germplasm accessions was more compact in a scatter diagram of PC1 vs. PC3 compared with PC1 vs. PC2. Groups I, II, III, and IV contained 142, 102, 2, and 3 sesame germplasm accessions, respectively. The two germplasm in Group III were collected from different regions, as were the three germplasm in Group IV. The results show that the distribution of sesame origin is wider than the regions examined in view of phenotypic diversity.  相似文献   

7.
芝麻EST-SSR标记的开发和初步研究   总被引：15，自引：4，他引：11  
为了加速分子标记在芝麻研究中的应用,利用网上现有的芝麻EST(expressed sequence tags)数据信息,开展了芝麻EST-SSR功能性标记的开发和利用研究。 在所有的3 328条芝麻EST序列中共确认得到1 785条非冗余EST序列。其中,在含有微卫星重复的148条序列中共检测有155个EST-SSR。非冗余EST序列总长为774.266 kb,平均每4.99 kb含有一个EST-SSR。EST-SSR的分布频率和特征分析表明,以AG/TC为重复基元(motif)的SSR出现最多,占总SSR的37.42%。利用这些序列,设计开发了50对EST-SSR引物,并分别选用36个芝麻、2个棉花、2个大豆和2个油葵进行多态性和通用性研究。其中44对引物在供试芝麻材料中扩增出条带,共产生108个位点,平均每对引物产生2.45个位点,多态信息含量(polymorphism information content, PIC)平均值为0.390。根据遗传相似性系数进行聚类,有26个芝麻材料聚类在两个大的亚类(III和IV)中,聚类结果表明芝麻的基因型与地理来源之间没有必然的联系。此外,分别有2对、3对和4对引物可以在棉花、大豆和油葵中进行通用性扩增。本研究证实这种全新开发的芝麻EST-SSR标记在芝麻遗传多样性分析、遗传图谱构建以及比较基因组等研究方面有广阔的利用前景。  相似文献   

8.
The allopolyploidization event that created cultivated oilseed rape Brassica napus L, followed by intense breeding, reduced its genetic diversity. Resynthesized (RS) B. napus L. obtained by interspecific hybridization between genotypes of B. rapa L. and B. oleracea L. can be a valuable source for broadening genetic diversity in cultivated oilseed rape. In this study, we determined the extent of DNA polymorphism among natural accessions of oilseed rape, resynthesized B. napus, their parental species and double-low quality semi-RS lines carrying the Rfo gene. Using 10 selected primer combinations, 522 polymorphic AFLP markers were scored in the complete set of 100 Brassica sp. To detect relationships between these genotypes, a cluster analysis was performed using the Jaccard’s distance. Resynthesized allopolyploids clustered directly between their diploid parents. Cultivated accessions of oilseed rape created a compact group away from resynthesized allopolyploids as well as semi-RS lines. The natural oilseed rape group, which consists of 49 cultivars and breeding lines of oilseed rape, is characterized by lower genetic diversity than the group of 33 accessions of resynthesized oilseed rape, and the analysis showed that the double-low quality semi-RS lines represent a specific genetic variation of B. napus. The de novo resynthesized B. napus lines and the semi-RS lines of double-low quality generated from them, provide a significant opportunity for enrichment the gene pool of oilseed rape.  相似文献   

9.
The growth of evergreen azaleas (Rhododendron spp.) can be altered by iron (Fe) chlorosis when plants are cultivated in a neutral-alkaline substrate. In this study, morphological and physiological responses to alkalinity and Fe deficiency were evaluated in five diploid Japanese azaleas to assess their potential as resources for breeding. R. obtusum ‘Kirin’, R. indicum ‘Shinsen’, R. × pulchrum ‘Sen-e-oomurasaki’, R. indicum ‘Osakazuki’, and R. ripense were pot cultivated in a peat-based substrate for 10 weeks, in acid and alkaline growing media with both adequate and inadequate Fe nutrition. Plant performance was generally affected by high pH of the substrate, while Fe deficiency by itself influenced few of the evaluated parameters, possibly due to the complex adaptive response mechanisms of these slow growing ornamental shrubs. According to the biochemical and physiological variations recorded on a long period of cultivation, R. indicum ‘Osakazuki’ reported the best performance. This azalea could be a valuable resource for breeders.  相似文献   

10.
D. H. Kim    G. Zur    Y. Danin-Poleg  S. W. Lee    K. B. Shim    C. W. Kang  Y. Kashi 《Plant Breeding》2002,121(3):259-262
Inter‐simple sequence repeats (ISSR) polymorphism was used to determine genetic relationships among 75 Sesamum indicum L. accessions of Korean and exotic sesame. Fourteen reliable ISSR primers were selected for the assessment of genetic diversity, yielding 79 amplification products. Of these polymerase chain reaction products, 33% revealed polymorphism among the 75 accessions. Genetic distances ranged from 0 to 0.255, with a mean genetic distance of 0.0687. The 75 accessions were divided into seven groups on the basis of unweighted pair‐group method with arithmetic averages (UPGMA) cluster analysis. The largest group consisted of 25 Korean cultivars, eight Korean breeding lines and 17 world‐wide accessions. The other groups included 25 accessions, several of which contained useful traits. The dendrogram did not indicate any clear division among sesame accessions based on their geographical origin. However, all Korean sesame cultivars except ‘Namsankkae’ were clustered in the same group, indicating a narrow gene pool. Some of the Korean breeding lines were spread along the dendrogram, showing enlargement of genetic diversity. The genetic diversity data uncovered in this study can be used in future breeding programmes.  相似文献   

11.
Summary Four hundred sesame (Sesamum indicum L.) lines selected by five methods from five crosses were tested for yield and other agronomic characters in F6 and F7. More high yielding lines were isolated by the bulk method and in the cross involving two local cultivars when two seasons means and performance in each individual season were considered. The cross involving two exotic cultivars did not produce a single line superior to local recommended variety. The 80 highest yielding lines recorded a 10.8% increase in yield compared to the mean of 400 lines. Thirty five lines were among the top 20% both seasons with a 13.2% increase in yield. Highly significant seasonal and population effects were recorded. There were no significant differences among the methods of selection although the yield differences among lines were highly significant. Interactions of seasons × populations, seasons × methods, populations × methods and seasons × populations × methods were highly significant. The results indicate that simple and less expensive bulk method may be used with equal success as the pedigree, single seed descent or early generation testing methods when selecting for yield in segregating sesame populations. The importance of inclusion of a high yielding, locally adapted cultivar in the crossing programmes for yield breeding of sesame has also been revealed.Abbreviations BM Bulk method - EGT Early generation testing - G × E Genotype × environment - MSS Modified single seed descent - PM Pedigree method - SSD Single seed descent  相似文献   

12.
Sesame (Sesamum indicum L.) is one of the most important oil seed crops, which has been used as a traditional health food. The objective of this study was to investigate the changes of leaf cuticular waxes during plant growth from 5 to 75 days after seedling emergence, and the variation of leaf waxes with different leaf position; top, middle, and lower positions, using four Korean sesame cultivars, Ahnsan, Danbaeck, Hanseom, and Kyeongheuk. Alkanes in lower leaves and aldehydes in top leaves among leaf positions were the most abundant, with alkanes being with major portion in all leaf position of four sesame cultivars. Total leaf wax load decreased around three-fold between 5 and 30 days, and then remained constant up to day 75. The percentages of alkanes and aldehydes increased between 5 and 15 days and then changed little or increasingly, showing minor variation depending on sesame cultivars. The rate of increase of alkanes was slightly higher than that of aldehydes. Chain length of alkanes and aldehydes became longer from 5 to 30 days, and then remained almost constant till day 75. The major homologue in alkanes was the C29 at day 5 and the C33 constituent after day 30, while the major homologue in aldehydes was the C32 constituent continuously during leaf development. The results demonstrated that the chain length for alkane and aldehyde constituents changed increasingly by chain elongation and wax biosynthesis during leaf development of sesame.  相似文献   

13.
Soybean (Glycine max (L.) Merr.) seed contains small amounts of tocopherol, a non‐enzymatic antioxidant known as lipid‐soluble vitamin E (VE). Dietary VE contributes to a decreased risk of chronic diseases in humans and has several beneficial effects on resistance to stress in plants, and increasing VE content is an important breeding goal for increasing the nutritional value of soybean. In this study, quantitative trait loci (QTLs) underlying VE content with main, epistatic and QTL × environment effects were identified in a population of F5 : 6 recombinant inbred lines from a cross between ‘Hefeng 25’ (a low‐VE cultivar) and ‘OAC Bayfield’ (a high‐VE cultivar). A total of 18 QTLs were detected that showed additive main effects (a) and/or additive × environment interaction effects (ae) in different environments. Moreover, 19 epistatic pairs of QTLs were found to be associated with α‐tocopherol (α‐Toc), γ‐tocopherol (γ‐Toc), δ‐tocopherol (δ‐Toc) and total VE (TE) contents. The QTLs identified in multienvironments could provide more information about QTL by environment interactions and could be useful for the marker‐assistant selection of soybean cultivars with high seed VE contents.  相似文献   

14.
The oil content, the tocopherol composition, the plastochromanol-8 (P-8) content and the fatty acid composition (19 fatty acids) of the seed of 51 hemp (Cannabis sativa L.) genotypes were studied in the 2000 and 2001 seasons. The oil content of the hemp seed ranged from 26.25% (w/w) to 37.50%. Analysis of variance revealed significant effects of genotype, year and of the interaction (genotype × year) on the oil content. The oil contents of the 51 genotypes in 2000 and 2001 were correlated (r = 0.37**) and averaged 33.19 ± 1.45% in 2000 and 31.21 ± 0.96% in 2001. The -tocopherol, -tocopherol, -tocopherol, P-8- and -tocopherol contents of the 51 genotypes averaged 21.68 ± 3.19, 1.82 ± 0.49, 1.20 ± 0.40, 0.18 ± 0.07 and 0.16 ± 0.04 mg 100g–1 of seeds, respectively (2000 and 2001 data pooled). Hierarchical clustering of the fatty acid data did not group the hemp genotypes according to their geographic origin. The -linolenic acid yield of hemp (3–30 kg ha–1) was similar to the -linolenic acid yield of plant species that are currently used as sources of -linolenic acid (borage (19–30 kg ha–1), evening primrose (7–30 kg ha–1)). The linoleic acid yield of hemp (129–326 kg ha–1) was similar to flax (102–250 kg ha–1), but less than in sunflower (868–1320 kg ha–1). Significant positive correlations were detected between some fatty acids and some tocopherols. Even though the average content of P-8 in hemp seeds was only 1/120th of the average -tocopherol content, P-8 content was more closely correlated with the unsaturated fatty acid content than -tocopherol or any other tocopherol fraction. The average broad-sense heritabilities of the oil content, the antioxidants (tocopherols and P-8) and the fatty acids were 0.53, 0.14 and 0.23, respectively. The genotypes Fibrimon 56, P57, Juso 31, GB29, Beniko, P60, FxT, Félina 34, Ramo and GB18 were capable of producing the largest amounts of high quality hemp oil.  相似文献   

15.
芝麻核雄性不育系ms86-1小孢子败育过程的超微结构   总被引：3，自引：0，他引：3  
运用透射电子显微镜对芝麻核雄性不育系ms86-1的可育和不育花药进行了超微结构的比较观察。根据小孢子的细胞学形态特征,将芝麻花粉发育过程划分为小孢子母细胞形成期、减数分裂期、四分体期、单核小孢子早期、单核小孢子中期、单核小孢子晚期、花粉成熟期7个时期。对比观察表明芝麻核雄性不育的败育迹象起始于小孢子母细胞形成期,并伴随着进一步发育,败育现象逐渐明显,小孢子母细胞形成期小孢子母细胞壁形状不规则;减数分裂期小孢子母细胞壁严重扭曲变形,质膜外缺少早期外壁成分--原基粒棒;四分体期胼胝质壁外沉积物异常,呈绒毛状;四分体解体后形成畸形小孢子,孢子外壁不健全,绒毡层异常肥厚、降解延迟,释放极少量的畸形乌氏体;随后小孢子愈发皱缩,胞质凝集,内含物减少并逐渐凝聚成一团电子致密物质,最终走向完全败育。本研究揭示了不育小孢子的败育过程和败育特征,为深入研究芝麻核雄性不育败育机理奠定了基础。  相似文献   

16.
Alternaria sesami is a major pathogen causing Alternaria leaf spot, prevalent in all the sesame growing areas of the world. Fungicidal effect of Mikania scandens plant extract was evaluated against Alternaria leaf spot disease in Sesamum orientale. Methodology includes hydrodistillation of M. scandens using clevenger apparatus followed by GC-MS, GC-FID spectrometer analysis, changes in the activity of phenylalanine ammonia lyase (PAL), peroxidase (POX), total phenolic content, and isozyme pattern of superoxide dismutase in sesame. Aqueous M. scandens leaf extract showed remarkable inhibition of mycelial growth. Treatment of healthy S.orientale with M. scandens aqueous extract followed by fungal inoculation induced significantly high phenylalanine ammonia lyase activity; the initiator enzyme of secondary metabolic pathway followed by a substantial increase in cytosolic and membrane-bound peroxidase activity. The isozyme profile of superoxide dismutase showed no significant changes. Phenolic compounds also showed an increased profile. Bioassays were conducted under field conditions for two successive growing seasons (2011 and 2012) at the experimental farm which resulted in a sufficient decrease in both disease incidence and disease severity compared with the control. Thus, application of M. scandens aqueous extract to sesame initiated a series of biochemical changes in the plants which are considered to be a part of the plant defense response. Further studies designed to assess the role of the extract in the molecular signal induction of resistance against pathogens are in progress.  相似文献   

17.
Moderate levels of selfing despite high inbreeding depression (ID) make runner bean an excellent model for mixed-mating reproductive biology studies in legumes. This work assesses the extent of the ID variation and consistency at different plant growth stages through selfing generations in seven runner bean populations. Field-collected populations after previous isolated multiplication were hand-pollinated in an isolated greenhouse during five generations to produce progeny. Generations were compared for inbreeding effects (δ) on seed germination, survival to flower, and seed weight and yield. The outcrossing rates of the founder populations and the genetic variation and Wright’s ID at the population and generation level were estimated by using 35 polymorphic microsatellite loci. Neutral microsatellite loci were analyzed through generations and populations using different outlier tests to identify loci directly associated with adaptation to inbreeding. Our study revealed patterns of genetic diversity (H e  = 0.36) and outcrossing rates (ranged from 24 to 44 %) that are consistent with a mixed-mating system. Selfing-pollination procedure significantly affected germination and survival rates, yield, and to a lesser extent seed weight. Three loci had significant hits to genes related to embryonic development when performing BLAST searches to Phytozome database. Results showed a general inconsistency in δ across plant growth stages and populations, suggesting that different deleterious loci are acting at different stages. Inbreeding tended to purge individuals of deleterious recessive alleles to reduce ID. Variation among individuals within populations may lead to the development of inbreeding lineages with lower levels of ID. Several lines that have been self-pollinated for many generations became homozygous at almost all gene loci and produced a uniform population of true breeding progeny and acceptable performance.  相似文献   

18.
Wheat–Psathyrostachys huashanica Keng disomic addition line 12-3 was developed and characterized using genomic in situ hybridization (GISH), expressed sequence tag–sequence tagged site (EST–STS), and sequence characterized amplified region (SCAR) markers. Mitotic and meiotic GISH analyses indicated that it contained 42 wheat chromosomes and a pair of P. huashanica chromosomes. Eight EST–STS multiple-loci markers located on the homoeologous group 1 chromosomes of wheat amplified polymorphic bands in the 1Ns disomic addition line 12-3, which were unique to P. huashanica. These markers suggested that the introduced Ns chromosomes belonged to homoeologous group 1. Furthermore, diagnostic fragments of random amplified polymorphic DNA marker OPAG10986 and simple sequence repeat marker Xgwm601 135 were cloned, sequenced, and converted into SCAR markers, i.e., RHS153 and SHS10, respectively, which were validated using a range of distinct plant species and a complete set of wheat–P. huashanica disomic addition lines (1Ns–7Ns, 2n = 44 = 22 II). The results demonstrated that the SCAR markers targeted the Ns genome of P. huashanica and they were linked to the 1Ns chromosome. In addition, 12-3 was evaluated to test its leaf rust resistance in the adult stages and its agronomic traits. These newly developed EST–STS and SCAR markers will be powerful tools for wheat breeders who want to screen for genotypes containing the 1Ns chromosome, with low costs and high throughput.  相似文献   

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