Your browser doesn't support javascript.
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 1.383
Filtrar
1.
Science ; 367(6478)2020 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-32029600

RESUMO

Because environmentally degrading inorganic fertilizer use underlies current worldwide cereal yields, future agricultural sustainability demands enhanced nitrogen use efficiency. We found that genome-wide promotion of histone H3 lysine 27 trimethylation (H3K27me3) enables nitrogen-induced stimulation of rice tillering: APETALA2-domain transcription factor NGR5 (NITROGEN-MEDIATED TILLER GROWTH RESPONSE 5) facilitates nitrogen-dependent recruitment of polycomb repressive complex 2 to repress branching-inhibitory genes via H3K27me3 modification. NGR5 is a target of gibberellin receptor GIBBERELLIN INSENSITIVE DWARF1 (GID1)-promoted proteasomal destruction. DELLA proteins (characterized by the presence of a conserved aspartate-glutamate-leucine-leucine-alanine motif) competitively inhibit the GID1-NGR5 interaction and explain increased tillering of green revolution varieties. Increased NGR5 activity consequently uncouples tillering from nitrogen regulation, boosting rice yield at low nitrogen fertilization levels. NGR5 thus enables enhanced nitrogen use efficiency for improved future agricultural sustainability and food security.


Assuntos
Cromatina/metabolismo , Histonas/metabolismo , Nitrogênio/metabolismo , Oryza/metabolismo , Proteínas PII Reguladoras de Nitrogênio/metabolismo , Proteínas de Plantas/metabolismo , Agricultura , Grão Comestível/genética , Fertilizantes , Giberelinas/metabolismo , Metilação , Oryza/genética , Proteínas PII Reguladoras de Nitrogênio/genética , Proteínas de Plantas/genética , Complexo de Endopeptidases do Proteassoma/metabolismo
2.
Nat Commun ; 11(1): 988, 2020 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-32080171

RESUMO

Increasing grain yield of maize (Zea mays L.) is required to meet the rapidly expanding demands for maize-derived food, feed, and fuel. Breeders have enhanced grain productivity of maize hybrids by pyramiding desirable characteristics for larger ears. However, loci selected for improving grain productivity remain largely unclear. Here, we show that a serine/threonine protein kinase encoding gene KERNEL NUMBER PER ROW6 (KNR6) determines pistillate floret number and ear length. Overexpression of KNR6 or introgression of alleles lacking the insertions of two transposable elements in the regulatory region of KNR6 can significantly enhance grain yield. Further in vitro evidences indicate that KNR6 can interact with an Arf GTPase-activating protein (AGAP) and its phosphorylation by KNR6 may affect ear length and kernel number. This finding provides knowledge basis to enhance maize hybrids grain yield.


Assuntos
Proteínas de Plantas/genética , Proteínas Serina-Treonina Quinases/genética , Zea mays/genética , Mapeamento Cromossômico , Grão Comestível/enzimologia , Grão Comestível/genética , Grão Comestível/crescimento & desenvolvimento , Proteínas Ativadoras de GTPase/metabolismo , Genes de Plantas , Fenótipo , Fosforilação , Melhoramento Vegetal , Proteínas de Plantas/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Locos de Características Quantitativas , Zea mays/enzimologia , Zea mays/crescimento & desenvolvimento
3.
PLoS One ; 15(1): e0223086, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31899771

RESUMO

Rice wild relatives (RWR) constitute an extended gene pool that can be tapped for the breeding of novel rice varieties adapted to abiotic stresses such as iron (Fe) toxicity. Therefore, we screened 75 Oryza genotypes including 16 domesticated O. sativa genotypes, one O. glaberrima, and 58 RWR representing 21 species, for tolerance to Fe toxicity. Plants were grown in a semi-artificial greenhouse setup, in which they were exposed either to control conditions, an Fe shock during the vegetative growth stage (acute treatment), or to a continuous moderately high Fe level (chronic treatment). In both stress treatments, foliar Fe concentrations were characteristic of Fe toxicity, and plants developed foliar stress symptoms, which were more pronounced in the chronic Fe stress especially toward the end of the growing season. Among the genotypes that produced seeds, only the chronic stress treatment significantly reduced yields due to increases in spikelet sterility. Moreover, a moderate but non-significant increase in grain Fe concentrations, and a significant increase in grain Zn concentrations were seen in chronic stress. Both domesticated rice and RWR exhibited substantial genotypic variation in their responses to Fe toxicity. Although no RWR strikingly outperformed domesticated rice in Fe toxic conditions, some genotypes scored highly in individual traits. Two O. meridionalis accessions were best in avoiding foliar symptom formation in acute Fe stress, while an O. rufipogon accession produced the highest grain yields in both chronic and acute Fe stress. In conclusion, this study provides the basis for using interspecific crosses for adapting rice to Fe toxicity.


Assuntos
Resistência à Doença/genética , Ferro/toxicidade , Oryza/genética , Doenças das Plantas/genética , Animais , Grão Comestível/efeitos dos fármacos , Grão Comestível/genética , Grão Comestível/crescimento & desenvolvimento , Etanol , Genótipo , Oryza/efeitos dos fármacos , Oryza/crescimento & desenvolvimento , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/genética , Folhas de Planta/crescimento & desenvolvimento , Sementes/genética , Sementes/crescimento & desenvolvimento , Estresse Fisiológico/efeitos dos fármacos , Estresse Fisiológico/genética
4.
Mol Genet Genomics ; 295(2): 465-474, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31863176

RESUMO

Rice yield potential is partially affected by grain size and weight, which associates with a great number of genes and QTLs. However, it is still unclear that how multiple alleles in different genes take a combined effect on grain shape/size. Here, we investigated seven core grain size-related functional genes (GL7, GS3, GW8, GS5, TGW6, WTG1, and An-1) and observed a wide phenotypic variation for five agronomic traits (grain length, grain width, grain length-width ratio, grain thickness and thousand-grain weight) in 521 rice germplasm. The correlation analysis showed a strong association among these grain traits which have distinct impacts on determining the final rice grain size. Genotyping analysis demonstrated that a relatively small number of allele combinations were preserved in the diverse population and these allele combinations were significantly associated with differences in grain size. Furthermore, alleles were regarded as individual variables to develop the multiple regression equation. We found that B and C allelic types of GS3 and conventional type of WTG1 played relevant roles in grain size and thousand-grain weight, separately. The models would conduce to devise instructive approaches by selecting appropriate candidate alleles, which could fuel further research for breeding preferred grain shape and high-yielding crop.


Assuntos
Grão Comestível/genética , Oryza/genética , Proteínas de Plantas/genética , Locos de Características Quantitativas/genética , Alelos , Mapeamento Cromossômico , Cromossomos de Plantas/genética , Grão Comestível/crescimento & desenvolvimento , Haplótipos/genética , Oryza/crescimento & desenvolvimento , Fenótipo
5.
Plant Mol Biol ; 102(4-5): 373-388, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31872309

RESUMO

KEY MESSAGE: CRISPR-edited variants at the 3'-end of OsLOGL5's coding sequence (CDS), significantly increased rice grain yield under well-watered, drought, normal nitrogen, and low nitrogen field conditions at multiple geographical locations. Cytokinins impact numerous aspects of plant growth and development. This study reports that constitutive ectopic overexpression of a rice cytokinin-activation enzyme-like gene, OsLOGL5, significantly reduced primary root growth, tiller number, and yield. Conversely, mutations at the 3'-end of OsLOGL5 CDS resulted in normal rice plant morphology but with increased grain yield under well-watered, drought, normal nitrogen, and low nitrogen field conditions at multiple geographical locations. Six gene edited variants (Edit A to F) were created and tested in the field. Edit-B and Edit-F plants increased, but Edit-D and Edit-E plants decreased, the panicle number per plant. All OsLOGL5-edited plants significantly increased seed setting rate, total grain numbers, full-filled grain numbers per panicle, and thousand seed weight under drought conditions, suggesting that OsLOGL5 is likely involved in the regulation of both seed development and grain filling processes. Our results indicate that the C-terminal end of OsLOGL5 protein plays an important role in regulating rice yield improvement under different abiotic stress conditions, and OsLOGL5 is important for rice yield enhancement and stability.


Assuntos
Citocininas/metabolismo , Grão Comestível/genética , Oryza/genética , Proteínas de Plantas/metabolismo , Sistemas CRISPR-Cas , Secas , Grão Comestível/enzimologia , Edição de Genes , Regulação da Expressão Gênica de Plantas , Nitrogênio , Oryza/enzimologia , Proteínas de Plantas/genética , Raízes de Plantas/fisiologia , Domínios Proteicos , Sementes/fisiologia , Estresse Fisiológico
6.
Int J Mol Sci ; 21(1)2019 Dec 25.
Artigo em Inglês | MEDLINE | ID: mdl-31881728

RESUMO

Secondary traits from high-throughput phenotyping could be used to select for complex target traits to accelerate plant breeding and increase genetic gains. This study aimed to evaluate the potential of using spectral reflectance indices (SRI) for indirect selection of winter-wheat lines with high yield potential and to assess the effects of including secondary traits on the prediction accuracy for yield. A total of five SRIs were measured in a diversity panel, and F5 and doubled haploid wheat breeding populations planted between 2015 and 2018 in Lind and Pullman, WA. The winter-wheat panels were genotyped with 11,089 genotyping-by-sequencing derived markers. Spectral traits showed moderate to high phenotypic and genetic correlations, indicating their potential for indirect selection of lines with high yield potential. Inclusion of correlated spectral traits in genomic prediction models resulted in significant (p < 0.001) improvement in prediction accuracy for yield. Relatedness between training and test populations and heritability were among the principal factors affecting accuracy. Our results demonstrate the potential of using spectral indices as proxy measurements for selecting lines with increased yield potential and for improving prediction accuracy to increase genetic gains for complex traits in US Pacific Northwest winter wheat.


Assuntos
Seleção Genética , Triticum/genética , Grão Comestível/genética , Grão Comestível/metabolismo , Genoma de Planta , Genótipo , Fenótipo , Análise de Componente Principal , Triticum/crescimento & desenvolvimento
7.
BMC Genomics ; 20(1): 1025, 2019 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-31881839

RESUMO

BACKGROUND: Agropyron cristatum (L.) Gaertn. (2n = 4x = 28; genomes PPPP) is a wild relative of common wheat (Triticum aestivum L.) and provides many desirable genetic resources for wheat improvement. However, there is still a lack of reference genome and transcriptome information for A. cristatum, which severely impedes functional and molecular breeding studies. RESULTS: Single-molecule long-read sequencing technology from Pacific Biosciences (PacBio) was used to sequence full-length cDNA from a mixture of leaves, roots, stems and caryopses and constructed the first full-length transcriptome dataset of A. cristatum, which comprised 44,372 transcripts. As expected, the PacBio transcripts were generally longer and more complete than the transcripts assembled via the Illumina sequencing platform in previous studies. By analyzing RNA-Seq data, we identified tissue-enriched transcripts and assessed their GO term enrichment; the results indicated that tissue-enriched transcripts were enriched for particular molecular functions that varied by tissue. We identified 3398 novel and 1352 A. cristatum-specific transcripts compared with the wheat gene model set. To better apply this A. cristatum transcriptome, the A. cristatum transcripts were integrated with the wheat genome as a reference sequence to try to identify candidate A. cristatum transcripts associated with thousand-grain weight in a wheat-A. cristatum translocation line, Pubing 3035. CONCLUSIONS: Full-length transcriptome sequences were used in our study. The present study not only provides comprehensive transcriptomic insights and information for A. cristatum but also proposes a new method for exploring the functional genes of wheat relatives under a wheat genetic background. The sequence data have been deposited in the NCBI under BioProject accession number PRJNA534411.


Assuntos
Agropyron/genética , Grão Comestível/genética , Genes de Plantas , Sequenciamento de Nucleotídeos em Larga Escala , Característica Quantitativa Herdável , Transcriptoma , Mapeamento Cromossômico , Cromossomos de Plantas , Biologia Computacional/métodos , Bases de Dados Genéticas , Anotação de Sequência Molecular
8.
BMC Plant Biol ; 19(1): 483, 2019 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-31703630

RESUMO

BACKGROUND: Wheat is a momentous crop and feeds billions of people in the world. The improvement of wheat yield is very important to ensure world food security. Normal development of grain is the essential guarantee for wheat yield formation. The genetic study of grain phenotype and identification of key genes for grain filling are of great significance upon dissecting the molecular mechanism of wheat grain morphogenesis and yield potential. RESULTS: Here we identified a pair of defective kernel (Dek) isogenic lines, BL31 and BL33, with plump and shrunken mature grains, respectively, and constructed a genetic population from the BL31/BL33 cross. Ten chromosomes had higher frequency of polymorphic single nucleotide polymorphism (SNP) markers between BL31 and BL33 using Wheat660K chip. Totally 783 simple sequence repeat (SSR) markers were chosen from the above chromosomes and 15 of these were integrated into two linkage groups using the genetic population. Genetic mapping identified three QTL, QDek.caas-3BS.1, QDek.caas-3BS.2 and QDek.caas-4AL, explaining 14.78-18.17%, 16.61-21.83% and 19.08-28.19% of phenotypic variances, respectively. Additionally, five polymorphic SNPs from Wheat660K were successfully converted into cleaved amplified polymorphic sequence (CAPS) markers and enriched the target regions of the above QTL. Biochemical analyses revealed that BL33 has significantly higher grain sucrose contents at filling stages and lower mature grain starch contents than BL31, indicating that the Dek QTL may be involved in carbohydrate metabolism. As such, the candidate genes for each QTL were predicated according to International Wheat Genome Sequence Consortium (IWGSC) RefSeq v1.0. CONCLUSIONS: Three major QTL for Dek were identified and their causal genes were predicted, laying a foundation to conduct fine mapping and dissect the regulatory mechanism underlying Dek trait in wheat.


Assuntos
Ligação Genética , Genoma de Planta , Genótipo , Fenótipo , Locos de Características Quantitativas/genética , Triticum/genética , Mapeamento Cromossômico , Grão Comestível/genética , Técnicas de Genotipagem , Triticum/metabolismo
9.
BMC Plant Biol ; 19(1): 502, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31730480

RESUMO

BACKGROUND: Selenium (Se) is a beneficial element for higher plants and essential for mammals. To study the effect of the foliar application of sodium selenate on fragrant rice performance, a pot experiment was conducted in Guangdong, China. At the initial heading stage, one-time foliar application of sodium selenate with concentrations of 0, 10, 20, 30, 40 and 50 µmol·L- 1 (named CK, Se1, Se2, Se3, Se4 and Se5, respectively) were foliar applied on two fragrant rice varieties, 'Meixiangzhan-2' and 'Xiangyaxiangzhan'. RESULTS: Selenate application at the initial heading stage not only improved the grain yield of fragrant rice by increasing the seed-setting rate and grain weight, but also promoted the grain quality by increasing crude protein contents and lowering the chalky rice rate. Furthermore, Se applications enhanced the biosynthesis of 2-acetyl-1- pyrroline (2-AP), the main aromatic compound, by increasing the contents of precursors (△1- pyrroline, proline and pyrroline-5-carboxylic acid (P5C)) and the activities of enzymes (proline dehydrogenase (PRODH), △1-pyrroline-5-carboxylic acid synthetase (P5CS), and ornithine aminotransferase (OAT)) in fragrant rice. The results also showed that foliar application of sodium selenate enhanced the antioxidant system of both varieties by promoting the activities of peroxidase (POD), superoxide dismutase (SOD), catalase (CAT) and reducing the contents of malondialdehyde (MDA). Furthermore, the real-time PCR analyses depicted that foliar application of selenate up-regulated the GPX1, GPX4 and CATC transcripts. The higher antioxidative enzymatic activities might strength the stress resistant to ensure the stability of yield in fragrant rice form abiotic stress. CONCLUSIONS: Foliar applications of sodium selenate at the initial heading stage increased the grain 2-AP content by enhancing the biosynthesis-related enzymes and precursors. The grain yield and quality of fragrant rice also increased due to selenate application. Furthermore, foliar application of selenate promoted the activities of enzymes such as POD, SOD and CAT and up-regulated the expression of gene GPX4, GPX1 and CATC.


Assuntos
Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Oryza/efeitos dos fármacos , Pirróis/metabolismo , Ácido Selênico/administração & dosagem , Antioxidantes/metabolismo , Biomassa , Catalase/metabolismo , Grão Comestível/efeitos dos fármacos , Grão Comestível/enzimologia , Grão Comestível/genética , Grão Comestível/crescimento & desenvolvimento , Malondialdeído/metabolismo , Oryza/enzimologia , Oryza/genética , Oryza/crescimento & desenvolvimento , Peroxidases/metabolismo , Proteínas de Plantas/metabolismo , Prolina/metabolismo , Superóxido Dismutase/metabolismo
10.
Ecotoxicol Environ Saf ; 186: 109795, 2019 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-31648160

RESUMO

Excessive cadmium (Cd) in rice grains is of great concern worldwide, particularly in southern China where heavy metal pollution in the soil is widespread. Much work has been done regarding the key genes responsible for Cd absorption, transport, and accumulation in rice, but little is known about the differences of Cd accumulation between indica and japonica rice cultivars during the reproductive stage. Furthermore, physiological parameters, such as nonstructural carbohydrate content, involved in Cd accumulation have not been fully elucidated. We studied several indica and japonica cultivars under three different Cd treatment levels and harvested them at different periods after heading. Differences in Cd accumulation between subspecies mainly were generated during the reproductive stage. An increase in the Cd pollution level caused the average absorption rate of Cd in the aerial parts of the indica cultivars in the reproductive stage to be 6.17, 4.52, and 3.89 times greater than that of the japonica cultivars across the three Cd treatments. The contribution of Cd absorption by shoots to Cd accumulation at the pre- or postheading stages was 33.8% and 66.2% in indica, and 44.9% and 55.1% in japonica. We found a significant negative correlation between Cd content in the rice grains and the content of nonstructural carbohydrates in the sheath (P < 0.05). Cd translocation from sheath to grain occurred along with sugar transfer in the indica cultivars. The Cd content of the indica cultivar grain was 1.84-4.14 times higher than that of the japonica cultivars (P < 0.05). The japonica cultivars thus met the cereal Cd limits of China (0.2 mg kg-1) under low and moderate soil Cd pollution. These findings are helpful for the selection of proper cultivars and field management practices to alleviate Cd exposure risk in rice production.


Assuntos
Cádmio/metabolismo , Oryza/classificação , Oryza/metabolismo , Poluentes do Solo/metabolismo , China , Grão Comestível/genética , Grão Comestível/metabolismo , Metais Pesados/análise , Oryza/genética , Brotos de Planta/genética , Brotos de Planta/metabolismo , Especificidade da Espécie , Açúcares/metabolismo
11.
Nat Genet ; 51(10): 1530-1539, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31548720

RESUMO

Bread wheat improvement using genomic tools is essential for accelerating trait genetic gains. Here we report the genomic predictabilities of 35 key traits and demonstrate the potential of genomic selection for wheat end-use quality. We also performed a large genome-wide association study that identified several significant marker-trait associations for 50 traits evaluated in South Asia, Africa and the Americas. Furthermore, we built a reference wheat genotype-phenotype map, explored allele frequency dynamics over time and fingerprinted 44,624 wheat lines for trait-associated markers, generating over 7.6 million data points, which together will provide a valuable resource to the wheat community for enhancing productivity and stress resilience.


Assuntos
Resistência à Doença/genética , Genômica/métodos , Locos de Características Quantitativas , Estresse Fisiológico/imunologia , Triticum/crescimento & desenvolvimento , Triticum/imunologia , Ascomicetos/fisiologia , Mapeamento Cromossômico , Grão Comestível/genética , Grão Comestível/crescimento & desenvolvimento , Estudos de Associação Genética , Marcadores Genéticos , Genoma de Planta , Estudo de Associação Genômica Ampla , Melhoramento Vegetal , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Seleção Genética , Estresse Fisiológico/genética , Triticum/genética
12.
Genes (Basel) ; 10(9)2019 09 10.
Artigo em Inglês | MEDLINE | ID: mdl-31510067

RESUMO

Late embryogenesis-abundant (LEA) genes play important roles in plant growth and development, especially the cellular dehydration tolerance during seed maturation. In order to comprehensively understand the roles of LEA family members in wheat, we carried out a series of analyses based on the latest genome sequence of the bread wheat Chinese Spring. 121 Triticum aestivum L. LEA (TaLEA) genes, classified as 8 groups, were identified and characterized. TaLEA genes are distributed in all chromosomes, most of them with a low number of introns (≤3). Expression profiles showed that most TaLEA genes expressed specifically in grains. By qRT-PCR analysis, we confirmed that 12 genes among them showed high expression levels during late stage grain maturation in two spring wheat cultivars, Yangmai16 and Yangmai15. For most genes, the peak of expression appeared earlier in Yangmai16. Statistical analysis indicated that expression level of 8 genes in Yangmai 16 were significantly higher than Yangmai 15 at 25 days after anthesis. Taken together, our results provide more knowledge for future functional analysis and potential utilization of TaLEA genes in wheat breeding.


Assuntos
Grão Comestível/genética , Genoma de Planta , Proteínas de Plantas/genética , Triticum/genética , Grão Comestível/crescimento & desenvolvimento , Proteínas de Plantas/metabolismo , Triticum/crescimento & desenvolvimento
13.
Genes (Basel) ; 10(9)2019 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-31480272

RESUMO

ZmPGP1, involved in the polar auxin transport, has been shown to be associated with plant height, leaf angle, yield traits, and root development in maize. To explore natural variation and domestication selection of ZmPGP1, we re-sequenced the ZmPGP1 gene in 349 inbred lines, 68 landraces, and 32 teosintes. Sequence polymorphisms, nucleotide diversity, and neutral tests revealed that ZmPGP1 might be selected during domestication and improvement processes. Marker-trait association analysis in inbred lines identified 11 variants significantly associated with 4 plant architecture and 5 ear traits. SNP1473 was the most significant variant for kernel length and ear grain weight. The frequency of an increased allele T was 40.6% in teosintes, and it was enriched to 60.3% and 89.1% during maize domestication and improvement. This result revealed that ZmPGP1 may be selected in the domestication and improvement process, and significant variants could be used to develop functional markers to improve plant architecture and ear traits in maize.


Assuntos
Transportadores de Cassetes de Ligação de ATP/genética , Proteínas de Plantas/genética , Polimorfismo Genético , Seleção Artificial , Zea mays/genética , Transportadores de Cassetes de Ligação de ATP/metabolismo , Domesticação , Grão Comestível/genética , Grão Comestível/crescimento & desenvolvimento , Proteínas de Plantas/metabolismo , Característica Quantitativa Herdável , Zea mays/crescimento & desenvolvimento
14.
Genes (Basel) ; 10(9)2019 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-31480460

RESUMO

Use of genetic markers and genomic prediction might improve genetic gain for quality traits in wheat breeding programs. Here, flour yield and Alveograph quality traits were inspected in 635 F6 winter wheat breeding lines from two breeding cycles. Genome-wide association studies revealed single nucleotide polymorphisms (SNPs) on chromosome 5D significantly associated with flour yield, Alveograph P (dough tenacity), and Alveograph W (dough strength). Additionally, SNPs on chromosome 1D were associated with Alveograph P and W, SNPs on chromosome 1B were associated with Alveograph P, and SNPs on chromosome 4A were associated with Alveograph L (dough extensibility). Predictive abilities based on genomic best linear unbiased prediction (GBLUP) models ranged from 0.50 for flour yield to 0.79 for Alveograph W based on a leave-one-out cross-validation strategy. Predictive abilities were negatively affected by smaller training set sizes, lower genetic relationship between lines in training and validation sets, and by genotype-environment (G×E) interactions. Bayesian Power Lasso models and genomic feature models resulted in similar or slightly improved predictions compared to GBLUP models. SNPs with the largest effects can be used for screening large numbers of lines in early generations in breeding programs to select lines that potentially have good quality traits. In later generations, genomic predictions might be used for a more accurate selection of high quality wheat lines.


Assuntos
Grão Comestível/genética , Farinha/normas , Estudo de Associação Genômica Ampla/métodos , Melhoramento Vegetal/métodos , Característica Quantitativa Herdável , Triticum/genética , Algoritmos , Grão Comestível/normas , Polimorfismo de Nucleotídeo Único , Locos de Características Quantitativas
15.
J Genet ; 982019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31544775

RESUMO

Iron (Fe) and zinc (Zn) deficiencies are wide spread in South Asia and Africa. Biofortification of food crops is a viable means of addressing micronutrient deficiencies. Lentil is an important pulse crop that provides affordable source of proteins, minerals, fibre and carbohydrates for micronutrient deficient countries. An association mapping (AM) panel of 96 diverse lentil genotypes from India and Mediterranean region was evaluated for three seasons and genotyped using 80 polymorphic simple-sequence repeat (SSR) markers for identification of the markers associated with grain Fe and Zn concentrations. A Bayesian model based clustering identified five subpopulations, adequately explaining the genetic structure of the AM panel. The linkage disequilibrium (LD) analysis using mixed linear model (MLM) identified two SSR markers, GLLC106 and GLLC108, associated with grain Fe concentration explaining 17% and 6% phenotypic variation, respectively and three SSR markers (PBALC 364, PBALC 92 and GLLC592) associated with grain Zn concentration, explaining 6%, 8% and 13% phenotypic variation, respectively. The identified SSRs exhibited consistent performance across three seasons and have potential for utilization in lentil molecular breeding programme.


Assuntos
Ferro/metabolismo , Lens (Planta)/genética , Zinco/metabolismo , África , Teorema de Bayes , Biofortificação , DNA de Plantas/genética , Grão Comestível/genética , Ligação Genética , Genótipo , Índia , Lens (Planta)/metabolismo , Modelos Lineares , Locos de Características Quantitativas
16.
BMC Plant Biol ; 19(1): 392, 2019 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-31500559

RESUMO

BACKGROUND: Utilization of heterosis in maize could be critical in maize breeding for boosting grain yield. However, the genetic architecture of heterosis is not fully understood. To dissect the genetic basis of yield-related traits and heterosis in maize, 301 recombinant inbred lines derived from 08 to 641 × YE478 and 298 hybrids from the immortalized F2 (IF2) population were used to map quantitative trait loci (QTLs) for nine yield-related traits and mid-parent heterosis. RESULTS: We observed 156 QTLs, 28 pairs of loci with epistatic interaction, and 10 significant QTL × environment interactions in the inbred and hybrid mapping populations. The high heterosis in F1 and IF2 populations for kernel weight per ear (KWPE), ear weight per ear (EWPE), and kernel number per row (KNPR) matched the high percentages of QTLs (over 50%) for those traits exhibiting overdominance, whereas a notable predominance of loci with dominance effects (more than 70%) was observed for traits that show low heterosis such as cob weight per ear (CWPE), rate of kernel production (RKP), ear length (EL), ear diameter (ED), cob diameter, and row number (RN). The environmentally stable QTL qRKP3-2 was identified across two mapping populations, while qKWPE9, affecting the trait mean and the mid-parent heterosis (MPH) level, explained over 18% of phenotypic variations. Nine QTLs, qEWPE9-1, qEWPE10-1, qCWPE6, qEL8, qED2-2, qRN10-1, qKWPE9, qKWPE10-1, and qRKP4-3, accounted for over 10% of phenotypic variation. In addition, QTL mapping identified 95 QTLs that were gathered together and integrated into 33 QTL clusters on 10 chromosomes. CONCLUSIONS: The results revealed that (1) the inheritance of yield-related traits and MPH in the heterotic pattern improved Reid (PA) × Tem-tropic I (PB) is trait-dependent; (2) a large proportion of loci showed dominance effects, whereas overdominance also contributed to MPH for KNPR, EWPE, and KWPE; (3) marker-assisted selection for markers at genomic regions 1.09-1.11, 2.04, 3.08-3.09, and 10.04-10.05 contributed to hybrid performance per se and heterosis and were repeatedly reported in previous studies using different heterotic patterns is recommended.


Assuntos
Grão Comestível/genética , Vigor Híbrido/genética , Locos de Características Quantitativas , Zea mays/genética , Mapeamento Cromossômico , Grão Comestível/fisiologia , Epistasia Genética/genética , Zea mays/fisiologia
17.
Plant Sci ; 288: 110214, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31521222

RESUMO

Biofortification of staple crops with essential micronutrients is the sustainable way to overcome the hidden hunger. A large number of quantitative trait loci (QTL) linked with grain micronutrient contents have been reported in different mapping studies. Identification of consistent QTLs across diverse genetic backgrounds is useful for candidate gene analysis and marker assisted selection of target traits. In this study, an up to date meta-analysis of grain iron and zinc associated QTLs was performed and 48 meta-QTLs (MQTLs) distributed across 12 rice chromosomes were identified. The 95% confidence intervals of identified genomic regions were significantly narrower than the average of their corresponding original QTLs. A total of 9308 genes/transcripts physically located within or near MQTL regions were retrieved and through prioritization of candidate genes (CGs) 663 non-redundant iron and zinc CGs were selected and studied in detailed. Several functionally characterized iron and zinc homoeostasis related genes e.g OsATM3, OsDMAS1, OsFRO2, OsNAS1-3, OsVIT2, OsYSL16, OsZIP3 and OsZIP7 were also included in our MQTL analysis. More than 64% genes were enriched with zinc and iron binding gene ontology terms and were involved in oxidation reduction process, carbohydrate metabolic process, regulation of transcription, trans-membrane transport, response to oxidative stress, cell redox homeostasis and proteolysis etc. In-silico transcriptomic analysis of rice identified 260 CGs which were regulated in response to iron and zinc stresses. We also identified at least 37 genes which were differentially expressed under both stress conditions and majority of these have not been studied in detailed before. Our results strongly indicate that majority of the MQTLs identified in this study are hotspots for grain iron and zinc concentration and are worth of intensive functional studies in near future.


Assuntos
Cromossomos de Plantas , Grão Comestível/química , Oryza/genética , Melhoramento Vegetal , Locos de Características Quantitativas , Mapeamento Cromossômico , Grão Comestível/genética , Genes de Plantas , Ferro/metabolismo , Zinco/metabolismo
19.
Science ; 365(6454): 658-664, 2019 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-31416957

RESUMO

Increased planting densities have boosted maize yields. Upright plant architecture facilitates dense planting. Here, we cloned UPA1 (Upright Plant Architecture1) and UPA2, two quantitative trait loci conferring upright plant architecture. UPA2 is controlled by a two-base sequence polymorphism regulating the expression of a B3-domain transcription factor (ZmRAVL1) located 9.5 kilobases downstream. UPA2 exhibits differential binding by DRL1 (DROOPING LEAF1), and DRL1 physically interacts with LG1 (LIGULELESS1) and represses LG1 activation of ZmRAVL1 ZmRAVL1 regulates brd1 (brassinosteroid C-6 oxidase1), which underlies UPA1, altering endogenous brassinosteroid content and leaf angle. The UPA2 allele that reduces leaf angle originated from teosinte, the wild ancestor of maize, and has been lost during maize domestication. Introgressing the wild UPA2 allele into modern hybrids and editing ZmRAVL1 enhance high-density maize yields.


Assuntos
Grão Comestível/anatomia & histologia , Grão Comestível/genética , Regulação da Expressão Gênica de Plantas , Folhas de Planta/anatomia & histologia , Folhas de Planta/genética , Zea mays/anatomia & histologia , Zea mays/genética , Alelos , Sequência de Bases , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Brassinosteroides/metabolismo , Quimera , Clonagem Molecular , Domesticação , Proteínas de Ligação ao GTP/genética , Proteínas de Ligação ao GTP/metabolismo , Edição de Genes , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Polimorfismo Genético , Locos de Características Quantitativas
20.
BMC Genet ; 20(1): 68, 2019 08 14.
Artigo em Inglês | MEDLINE | ID: mdl-31412771

RESUMO

BACKGROUND: Yellow lupin (Lupinus luteus L.) is a promising grain legume for productive and sustainable crop rotations. It has the advantages of high tolerance to soil acidity and excellent seed quality, but its current yield potential is poor, especially in low rainfall environments. Key adaptation traits such as phenology and enhanced stress tolerance are often complex and controlled by several genes. Genomic-enabled technologies may help to improve our basic understanding of these traits and to provide selective markers in breeding. However, in yellow lupin there are very limited genomic resources to support research and no published information is available on the genetic control of adaptation traits. RESULTS: We aimed to address these deficiencies by developing the first linkage map for yellow lupin and conducting quantitative trait locus (QTL) analysis of yield under well-watered (WW) and water-deficit (WT) conditions. Two next-generation sequencing marker approaches - genotyping-by-sequencing (GBS) and Diversity Array Technology (DArT) sequencing - were employed to genotype a recombinant inbred line (RIL) population developed from a bi-parental cross between wild and domesticated parents. A total of 2,458 filtered single nucleotide polymorphism (SNP) and presence / absence variation (PAV) markers were used to develop a genetic map comprising 40 linkage groups, the first reported for this species. A number of significant QTLs controlling total biomass and 100-seed weight under two water (WW and WD) regimes were found on linkage groups YL-03, YL-09 and YL-26 that together explained 9 and 28% of total phenotypic variability. QTLs associated with length of the reproductive phase and time to flower were found on YL-01, YL-21, YL-35 and YL-40 that together explained a total of 12 and 44% of total phenotypic variation. CONCLUSION: These genomic resources and the QTL information offer significant potential for use in marker-assisted selection in yellow lupin.


Assuntos
Mapeamento Cromossômico , Produtos Agrícolas/genética , Grão Comestível/genética , Lupinus/genética , Locos de Características Quantitativas , Característica Quantitativa Herdável , Análise de Variância , Ligação Genética , Marcadores Genéticos , Genótipo , Endogamia , Fenótipo , Melhoramento Vegetal
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA