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1.
Plant J ; 119(1): 348-363, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38606539

RESUMO

The Phyllanthaceae family comprises a diverse range of plants with medicinal, edible, and ornamental value, extensively cultivated worldwide. Polyploid species commonly occur in Phyllanthaceae. Due to the rather complex genomes and evolutionary histories, their speciation process has been still lacking in research. In this study, we generated chromosome-scale haplotype-resolved genomes of two octoploid species (Phyllanthus emblica and Sauropus spatulifolius) in Phyllanthaceae family. Combined with our previously reported one tetraploid (Sauropus androgynus) and one diploid species (Phyllanthus cochinchinensis) from the same family, we explored their speciation history. The three polyploid species were all identified as allopolyploids with subgenome A/B. Each of their two distinct subgenome groups from various species was uncovered to independently share a common diploid ancestor (Ancestor-AA and Ancestor-BB). Via different evolutionary routes, comprising various scenarios of bifurcating divergence, allopolyploidization (hybrid polyploidization), and autopolyploidization, they finally evolved to the current tetraploid S. androgynus, and octoploid S. spatulifolius and P. emblica, respectively. We further discuss the variations in copy number of alleles and the potential impacts within the two octoploids. In addition, we also investigated the fluctuation of metabolites with medical values and identified the key factor in its biosynthesis process in octoploids species. Our study reconstructed the evolutionary history of these Phyllanthaceae species, highlighting the critical roles of polyploidization and hybridization in their speciation processes. The high-quality genomes of the two octoploid species provide valuable genomic resources for further research of evolution and functional genomics.


Assuntos
Genoma de Planta , Haplótipos , Hibridização Genética , Poliploidia , Genoma de Planta/genética , Haplótipos/genética , Filogenia , Especiação Genética , Evolução Molecular
2.
Plant Cell ; 33(3): 566-580, 2021 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-33955496

RESUMO

The external application of nitrogen (N) fertilizers is an important practice for increasing crop production. However, the excessive use of fertilizers significantly increases production costs and causes environmental problems, making the improvement of crop N-use efficiency (NUE) crucial for sustainable agriculture in the future. Here we show that the rice (Oryza sativa) NUE quantitative trait locus DULL NITROGEN RESPONSE1 (qDNR1), which is involved in auxin homeostasis, reflects the differences in nitrate (NO3-) uptake, N assimilation, and yield enhancement between indica and japonica rice varieties. Rice plants carrying the DNR1indica allele exhibit reduced N-responsive transcription and protein abundance of DNR1. This, in turn, promotes auxin biosynthesis, thereby inducing AUXIN RESPONSE FACTOR-mediated activation of NO3- transporter and N-metabolism genes, resulting in improved NUE and grain yield. We also show that a loss-of-function mutation at the DNR1 locus is associated with increased N uptake and assimilation, resulting in improved rice yield under moderate levels of N fertilizer input. Therefore, modulating the DNR1-mediated auxin response represents a promising strategy for achieving environmentally sustainable improvements in rice yield.


Assuntos
Ácidos Indolacéticos/metabolismo , Mutação com Perda de Função/genética , Nitrogênio/metabolismo , Oryza/genética , Oryza/metabolismo , Alelos , Homeostase/genética , Homeostase/fisiologia
3.
Planta ; 258(2): 42, 2023 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-37432475

RESUMO

MAIN CONCLUSION: A novel QTL GS6.1 increases yield per plant by controlling kernel size, plant architecture, and kernel filling in rice. Kernel size and plant architecture are critical agronomic traits that greatly influence kernel yield in rice. Using the single-segment substitution lines (SSSLs) with an indica cultivar Huajingxian74 as a recipient parent and American Jasmine as a donor parent, we identified a novel quantitative trait locus (QTL), named GS6.1. Near isogenic line-GS6.1 (NIL-GS6.1) produces long and narrow kernels by regulating cell length and width in the spikelet hulls, thus increasing the 1000-kernel weight. Compared with the control, the plant height, panicles per plant, panicle length, kernels per plant, secondary branches per panicle, and yield per plant of NIL-GS6.1 are increased. In addition, GS6.1 regulates the kernel filling rate. GS6.1 controls kernel size by modulating the transcription levels of part of EXPANSINs, kernel filling-related genes, and kernel size-related genes. These results indicate that GS6.1 might be beneficial for improving kernel yield and plant architecture in rice breeding by molecular design.


Assuntos
Oryza , Oryza/genética , Melhoramento Vegetal , Agricultura , Fenótipo , Locos de Características Quantitativas/genética
4.
Theor Appl Genet ; 136(11): 225, 2023 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-37847396

RESUMO

KEY MESSAGE: A novel QTL qGLF5 from Oryza rufipogon Griff. improves yield per plant and plant architecture in rice. Kernel size and plant architecture are critical agronomic traits that are key targets for improving crop yield. From the single-segment substitution lines of Oryza rufipogon Griff. in the indica cultivar Huajingxian74 (HJX74) background, we identified a novel quantitative trait locus (QTL), named qGLF5, which improves kernel shape, plant architecture, and yield per plant in rice. Compared with the control HJX74, the plant height, panicles per plant, panicle length, primary branches per panicle, secondary branches per panicle, and kernels per plant of the near-isogenic line-qGLF5 (NIL-qGLF5) are significantly increased. NIL-qGLF5 has long and narrow kernels by regulating cell number, cell length and width in the spikelet hulls. Yield per plant of NIL-qGLF5 is increased by 35.02% compared with that of HJX74. In addition, qGLF5 significantly improves yield per plant and plant architecture of NIL-gw5 and NIL-GW7. These results indicate that qGLF5 might be beneficial for improving plant architecture and kernel yield in rice breeding by molecular design.


Assuntos
Oryza , Mapeamento Cromossômico , Oryza/genética , Genes de Plantas , Melhoramento Vegetal , Locos de Características Quantitativas
5.
J Integr Plant Biol ; 65(8): 1890-1903, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37097077

RESUMO

Lipid droplet (LD) in vegetative tissues has recently been implicated in environmental responses in plants, but its regulation and its function in stress tolerance are not well understood. Here, we identified a Membrane Occupation and Recognition Nexus 1 (MORN1) gene as a contributor to natural variations of stress tolerance through genome-wide association study in Arabidopsis thaliana. Characterization of its loss-of-function mutant and natural variants revealed that the MORN1 gene is a positive regulator of plant growth, disease resistance, cold tolerance, and heat tolerance. The MORN1 protein is associated with the Golgi and is also partly associated with LD. Protein truncations that disrupt these associations abolished the biological function of the MORN1 protein. Furthermore, the MORN1 gene is a positive regulator of LD abundance, and its role in LD number regulation and stress tolerance is highly linked. Therefore, this study identifies MORN1 as a positive regulator of LD abundance and a contributor to natural variations of stress tolerance. It implicates a potential involvement of Golgi in LD biogenesis and strongly suggests a contribution of LD to diverse processes of plant growth and stress responses.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Gotículas Lipídicas/metabolismo , Estudo de Associação Genômica Ampla , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Complexo de Golgi/metabolismo , Regulação da Expressão Gênica de Plantas/genética , Plantas Geneticamente Modificadas/metabolismo , Estresse Fisiológico/genética
6.
Yi Chuan ; 45(9): 835-844, 2023 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-37731237

RESUMO

Kernel size and plant architecture play important roles in kernel yield in rice. Cloning and functional study of genes related to kernel size and plant architecture are of great significance for breeding high-yield rice. Using the single-segment substitution lines which developed with Oryza barthii as a donor parent and an elite indica cultivar Huajingxian74 (HJX74) as a recipient parent, we identified a novel QTL (quantitative trait locus), named qGL3.4, which controls kernel size and plant architecture. Compared with HJX74, the kernel length, kernel width, 1000-kernel weight, panicle length, kernels per plant, primary branches, yield per plant, and plant height of near isogenic line-qGL3.4 (NIL-qGL3.4) are increased, whereas the panicles per plant and secondary branches per panicle of NIL-qGL3.4 are comparable to those of HJX74. qGL3.4 was narrowed to a 239.18 kb interval on chromosome 3. Cell analysis showed that NIL-qGL3.4 controlled kernel size by regulating cell growth. qGL3.4 controls kernel size at least in part through regulating the transcription levels of EXPANSINS, GS3, GL3.1, PGL1, GL7, OsSPL13 and GS5. These results indicate that qGL3.4 might be beneficial for improving kernel yield and plant architecture in rice breeding.


Assuntos
Oryza , Oryza/genética , Melhoramento Vegetal , Ciclo Celular , Proliferação de Células , Locos de Características Quantitativas
7.
Mol Genet Genomics ; 296(6): 1279-1286, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34536132

RESUMO

Understanding dynamic changes in the genetic architecture of quantitative traits is crucial in developmental genetics. Functional mapping is an appropriate method that passes a mathematical equation to describe a biological developmental process with the genetic mapping framework. Appropriate genetic model and applicable mapping population are indispensable condition for functional mapping of important agronomic traits in plants. Based on the Wang-Lan-Ding model, we ever applied a DH population to carry out functional mapping QTLs underlying growth trajectory on tiller number. However, inconsistent genetic background among the DH lines might disturb the mapping results. With the advent of innovative research materials, single segment substitution lines, allows us to do more precise genetic analyses. Thus functional mapping was again conducted on tiller number using the Wang-Lan-Ding model and a single segment substitution line population with the genetic background of Huajingxian 74 so as to explore QTL dynamic mechanism to regulate developmental traits. We detected that all five single segment substitution lines harbored tillering QTLs with additives and/or dominances to influence the four functional parameters, the optimum tillering time (t0), the maximum tiller number (K), the tillering increased rate (r) and the tillering decreased rate (c), which were estimated from the Wang-Lan-Ding model and with some biological meaning. They mainly brought the inflexion point (t0) delay, the peak increase (K) and the degradation (c) acceleration, while the growth (r) slow down. Moreover, epistatic interactions among these QTLs were confirmed to be prevalent. A total of 39 significant epistatic effects were detected to associate with the four parameters, occupying 34.8% of 112 pairs of epistatic interactions investigated. Contrary to the QTL effects, these epistatic effects largely decreased t0, K and c, while increased r. Our results indicated that the five QTL effects and their epistatic effects significantly changed the shape and trajectory of tiller number via influence of the four functional parameters. Rational use of these QTLs is expected to improve tillering number of rice by molecular design breeding.


Assuntos
Mapeamento Cromossômico/métodos , Cromossomos de Plantas/genética , Oryza/genética , Locos de Características Quantitativas/genética , Epistasia Genética/genética , Modelos Teóricos , Oryza/classificação , Fenótipo , Melhoramento Vegetal/métodos
8.
Theor Appl Genet ; 134(4): 1253-1262, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33492412

RESUMO

KEY MESSAGE: Through substitution mapping strategy, two pairs of closely linked QTLs controlling stigma exsertion rate were dissected from chromosomes 2 and 3 and the four QTLs were fine mapped. Stigma exsertion rate (SER) is an important trait affecting the outcrossing ability of male sterility lines in hybrid rice. This complex trait was controlled by multiple QTLs and affected by environment condition. Here, we dissected, respectively, two pairs of tightly linked QTLs for SER on chromosomes 2 and 3 by substitution mapping. On chromosome 2, two linkage QTLs, qSER-2a and qSER-2b, were located in the region of 1288.0 kb, and were, respectively, delimited to the intervals of 234.9 kb and 214.3 kb. On chromosome 3, two QTLs, qSER-3a and qSER-3b, were detected in the region of 3575.5 kb and were narrowed down to 319.1 kb and 637.3 kb, respectively. The additive effects of four QTLs ranged from 7.9 to 9.0%. The epistatic effect produced by the interaction of qSER-2a and qSER-2b was much greater than that of qSER-3a and qSER-3b. The open reading frames were identified within the maximum intervals of qSER-2a, qSER-2b and qSER-3a, respectively. These results revealed that there are potential QTL clusters for SER in the two regions of chromosome 2 and chromosome 3. Fine mapping of the QTLs laid a foundation for cloning of the genes of SER.


Assuntos
Mapeamento Cromossômico/métodos , Cromossomos de Plantas/genética , Flores/crescimento & desenvolvimento , Ligação Genética , Oryza/crescimento & desenvolvimento , Locos de Características Quantitativas , Flores/genética , Oryza/genética , Fenótipo
9.
Theor Appl Genet ; 134(12): 3941-3950, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34420062

RESUMO

KEY MESSAGE: A quantitative trait locus GW10 is located on Chromosome 10 by map-based cloning, which encodes a P450 Subfamily protein. The GW10 regulates grain size and grain number in rice involved in the BR pathway. Grain size and grain number play extremely important roles in rice grain yield. Here, we identify GW10, which encodes a P450 subfamily protein and controls grain size and grain number by using Lemont (tropical japonica) as donor parent and HJX74 (indica) as recipient parent. The GW10 locus was mapped into a 14.6 kb region in HJX74 genomic on the long arm of chromosome 10. Lower expression of the gw10 in panicle is contributed to the shorter and narrower rice grain, and the increased number of grains per panicle. In contrast, overexpression of GW10 is contributed to longer and wider rice grain. Furthermore, the higher expression levels of some of the brassinosteroid (BR) biosynthesis and response genes are associated with the NIL-GW10. The sensitivity of the leaf angle to exogenous BR in NIL-GW10 is lower than that in NIL-gw10 and in the KO-GW10, which implied that the GW10 should involve in the brassinosteroid-mediated regulation of rice grain size and grain number.


Assuntos
Sistema Enzimático do Citocromo P-450/genética , Oryza/genética , Locos de Características Quantitativas , Sementes/crescimento & desenvolvimento , Mapeamento Cromossômico , Cruzamentos Genéticos , Grão Comestível/genética , Genes de Plantas , Oryza/crescimento & desenvolvimento
10.
Theor Appl Genet ; 134(8): 2613-2637, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34018019

RESUMO

KEY MESSAGE: Association analysis for ionomic concentrations of 20 elements identified independent genetic factors underlying the root and shoot ionomes of rice, providing a platform for selecting and dissecting causal genetic variants. Understanding the genetic basis of mineral nutrient acquisition is key to fully describing how terrestrial organisms interact with the non-living environment. Rice (Oryza sativa L.) serves both as a model organism for genetic studies and as an important component of the global food system. Studies in rice ionomics have primarily focused on above ground tissues evaluated from field-grown plants. Here, we describe a comprehensive study of the genetic basis of the rice ionome in both roots and shoots of 6-week-old rice plants for 20 elements using a controlled hydroponics growth system. Building on the wealth of publicly available rice genomic resources, including a panel of 373 diverse rice lines, 4.8 M genome-wide single-nucleotide polymorphisms, single- and multi-marker analysis pipelines, an extensive tome of 321 candidate genes and legacy QTLs from across 15 years of rice genetics literature, we used genome-wide association analysis and biparental QTL analysis to identify 114 genomic regions associated with ionomic variation. The genetic basis for root and shoot ionomes was highly distinct; 78 loci were associated with roots and 36 loci with shoots, with no overlapping genomic regions for the same element across tissues. We further describe the distribution of phenotypic variation across haplotypes and identify candidate genes within highly significant regions associated with sulfur, manganese, cadmium, and molybdenum. Our analysis provides critical insight into the genetic basis of natural phenotypic variation for both root and shoot ionomes in rice and provides a comprehensive resource for dissecting and testing causal genetic variants.


Assuntos
Mapeamento Cromossômico/métodos , Cromossomos de Plantas/genética , Regulação da Expressão Gênica de Plantas , Oryza/genética , Proteínas de Plantas/metabolismo , Raízes de Plantas/genética , Brotos de Planta/genética , Estudo de Associação Genômica Ampla , Oryza/crescimento & desenvolvimento , Fenótipo , Proteínas de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento , Brotos de Planta/crescimento & desenvolvimento , Locos de Características Quantitativas
11.
BMC Plant Biol ; 20(1): 478, 2020 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-33081724

RESUMO

BACKGROUND: Drought stress is an adverse factor with deleterious effects on several aspects of rice growth. However, the mechanism underlying drought resistance in rice remains unclear. To understand the molecular mechanism of the drought response in rice, drought-sensitive CSSL (Chromosome Single-substitution Segment Line) PY6 was used to map QTLs of sensitive phenotypes and to reveal the impact of the QTLs on transcriptional profiling. RESULTS: The QTL dss-1 was mapped onto the short arm of chromosome 1 of rice. According to transcriptomic analysis, the identified differentially expressed genes (DEGs) exhibited a downregulated pattern and were mainly enriched in photosynthesis-related GO terms, indicating that photosynthesis was greatly inhibited under drought. Further, according to weighted gene coexpression network analysis (WGCNA), specific gene modules (designating a group of genes with a similar expression pattern) were strongly correlated with H2O2 (4 modules) and MDA (3 modules), respectively. Likewise, GO analysis revealed that the photosynthesis-related GO terms were consistently overrepresented in H2O2-correlated modules. Functional annotation of the differentially expressed hub genes (DEHGs) in the H2O2 and MDA-correlated modules revealed cross-talk between abiotic and biotic stress responses for these genes, which were annotated as encoding WRKYs and PR family proteins, were notably differentially expressed between PY6 and PR403. CONCLUSIONS: We speculated that drought-induced photosynthetic inhibition leads to H2O2 and MDA accumulation, which can then trigger the reprogramming of the rice transcriptome, including the hub genes involved in ROS scavenging, to prevent oxidative stress damage. Our results shed light on and provide deep insight into the drought resistance mechanism in rice.


Assuntos
Regulação da Expressão Gênica de Plantas/genética , Genes de Plantas/genética , Oryza/fisiologia , Ácido Abscísico/metabolismo , Desidratação , Genes de Plantas/fisiologia , Peróxido de Hidrogênio/metabolismo , Malondialdeído/metabolismo , Oryza/genética , Oryza/metabolismo , Reguladores de Crescimento de Plantas/metabolismo , Folhas de Planta/metabolismo , Estômatos de Plantas/fisiologia , Transcriptoma
12.
BMC Plant Biol ; 20(1): 512, 2020 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-33172402

RESUMO

An amendment to this paper has been published and can be accessed via the original article.

13.
Int J Mol Sci ; 20(20)2019 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-31614592

RESUMO

As organelles for photosynthesis in green plants, chloroplasts play a vital role in solar energy capture and carbon fixation. The maintenance of normal chloroplast physiological functions is essential for plant growth and development. Low temperature is an adverse environmental stress that affects crop productivity. Low temperature severely affects the growth and development of plants, especially photosynthesis. To date, many studies have reported that chloroplasts are not only just organelles of photosynthesis. Chloroplasts can also perceive chilling stress signals via membranes and photoreceptors, and they maintain their homeostasis and promote photosynthesis by regulating the state of lipid membranes, the abundance of photosynthesis-related proteins, the activity of enzymes, the redox state, and the balance of hormones and by releasing retrograde signals, thus improving plant resistance to low temperatures. This review focused on the potential functions of chloroplasts in fine tuning photosynthesis processes under low-temperature stress by perceiving stress signals, modulating the expression of photosynthesis-related genes, and scavenging excess reactive oxygen species (ROS) in chloroplasts to survive the adverse environment.


Assuntos
Cloroplastos/metabolismo , Estresse Fisiológico , Viridiplantae/crescimento & desenvolvimento , Ciclo do Carbono , Temperatura Baixa , Regulação da Expressão Gênica no Desenvolvimento , Regulação da Expressão Gênica de Plantas , Fotossíntese , Proteínas de Plantas/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Viridiplantae/metabolismo
14.
Theor Appl Genet ; 130(6): 1191-1205, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28283703

RESUMO

KEY MESSAGE: A permanent advanced population containing 388 SSSLs was used for genetic analysis of seed dormancy; 25 QTLs including eight stable, six major and five new were identified. Seed dormancy (SD) is not only a complex biological phenomenon, but also a key practical problem in agricultural production closely related with pre-harvest sprouting (PHS). However, the genetic mechanisms of SD remain elusive. Here, we report the genetic dissection of SD in rice using 388 single segment substitution lines (SSSLs) derived from 16 donor parents. Continuous variation and positive correlations in seed germination percentages were observed in seven seasons. Genetic analysis revealed the narrow sense heritability in different seasons varied from 31.4 to 82.2% with an average value of 56.8%. In addition, 49 SSSLs exhibited significant difference to recipient parent HJX74 on SD in at least two seasons, and 12 of them were stably identified with putative QTLs in all of their corresponding cropping seasons. Based on substitution mapping, a total of 25 dormancy QTLs were detected on 11 chromosomes except the chromosome 5 with an interval length of 1.1 to 31.3 cM. The additive effects of these QTLs changed from -0.31 to -0.13, and the additive effect contributions ranged from 16.7 to 41.4%. Six QTLs, qSD3-2, qSD4-1, qSD7-1, qSD7-2, qSD7-3 and qSD11-2, showed large additive effect contributions (≥30%). Five QTLs, qSD3-3, qSD7-1, qSD7-4, qSD9-1 and qSD10-1, may represent novel ones. Furthermore, linkage and recombinant analysis delimited qSD7-1 to a locus 1.5 cM away from marker Oi2 and a 355-kb fragment flanked by RM1134 and Ui159, respectively. Taken together, this work conducts a comprehensive genetic dissection of SD and will provide more selections for breeding elite PHS-resistant rice varieties.


Assuntos
Oryza/genética , Dormência de Plantas/genética , Locos de Características Quantitativas , Mapeamento Cromossômico , Ligação Genética , Variação Genética , Oryza/fisiologia , Estações do Ano
15.
Breed Sci ; 66(5): 768-775, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28163593

RESUMO

Exploitation of the heterosis of hybrid rice has shown great success in the improvement of rice yields. However, few genotypes exhibit strong restoration ability as effective restorers of cytoplasmic male sterility (CMS) in the development of hybrid rice. In this study, we developed a platform for the breeding by design of CMS restorer lines based on a library of chromosomal single segment substitution lines (SSSLs) in the Huajingxian74 (HJX74) genetic background. The target genes for breeding by design, Rf34 and Rf44, which are associated with a strong restoration ability, and gs3, gw8, Wxg1 and Alk, which are associated with good grain quality, were selected from the HJX74 SSSL library. Through pyramiding of the target genes, a restorer line, H121R, was developed. The H121R line was then improved regarding blast resistance by pyramiding of the qBLAST11 gene. Hence, a new restorer line with blast resistance, H131R, was developed. The platform involving the Rf34 and Rf44 restorer genes would be used for the continuous improvement of restorer lines through breeding by design in rice.

16.
Breed Sci ; 65(3): 192-200, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26175615

RESUMO

Hua-jing-xian 74 and its 12 single segment substitution lines (SSSLs) in rice were used as crossing parents to construct a half diallel crossing population. A total number of 91 materials were grown under three planting densities. By analysis of average plant height (PH) over all environments 10 SSSLs were detected with significant additives and 6 SSSLs with significant dominances. These SSSLs were further tested under different densities respectively, indicating that some of single locus effects were sensitive to densities and the conditions under the density of 16.7 cm × 16.7 cm maybe inhibited the expressing of these PH QTLs. Qualitative and quantitative analyses of each four participating genotypes indicated that digenic interactions among these QTLs were prevalent. Of 66 tested interactions, about 42.4% were epistatic (P < 5%). Although some QTLs hadn't single locus effects, they were possible to form digenic interactions. A significant finding was that the detected epistases were mostly negative. Additionally, these epistases were also found being sensitive to planting densities, the conditions under the density of 10 cm × 16.7 cm perhaps promoted the expressing of epistatic interactions among PH QTLs.

17.
Sci Rep ; 14(1): 373, 2024 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-38172169

RESUMO

If there was no gene interaction, the gene aggregation effect would increase infinitely with the increase of gene number. Epistasis avoids the endless accumulation of gene effects, playing a role of homeostasis. To confirm the role, QTL epistases were analyzed by four single-segment substitution lines with heading date QTLs in this paper. We found that QTLs of three positive effects and one negative effect generated 62.5% negative dual QTL epistatic effects and 57.7% positive triple QTL epistatic effects, forming the relationship "positive QTLs-negative one order interactions-positive two order interactions". In this way, the aggregation effect of QTLs was partially neutralized by the opposite epistatic effect sum. There also were two exceptions, QTL OsMADS50 and gene Hd3a-2 were always with consistent effect directions with their epistases, implying they could be employed in pyramiding breeding with different objectives. This study elucidated the mechanism of epistatic interactions among four QTLs and provided valuable genetic resources for improving heading date in rice.


Assuntos
Oryza , Mapeamento Cromossômico , Oryza/genética , Fenótipo , Epistasia Genética , Cromossomos de Plantas , Melhoramento Vegetal , Homeostase/genética
18.
Rice (N Y) ; 17(1): 4, 2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-38185771

RESUMO

Rice chalkiness is a key limiting factor of high-quality rice. The breeding of low chalkiness varieties has always been a challenging task due to the complexity of chalkiness and its susceptibility to environmental factors. In previous studies, we identified six QTLs for the percentage of grain chalkiness (PGC), named qPGC5, qPGC6, qPGC8.1, qPGC8.2, qPGC9 and qPGC11, using single-segment substitution lines (SSSLs) with genetic background of Huajingxian 74 (HJX74). In this study, we utilized the six low chalkiness QTLs to develop 17 pyramiding lines with 2-4 QTLs. The results showed that the PGC decreased with the increase of QTLs in the pyramiding lines. The pyramiding lines with 4 QTLs significantly reduced the chalkiness of rice and reached the best quality level. Among the six QTLs, qPGC5 and qPGC6 showed greater additive effects and were classified as Group A, while the other four QTLs showed smaller additive effects and were classified as Group B. In pyramiding lines, although the presence of epistasis, additivity remained the main component of QTL effects. qPGC5 and qPGC6 showed stronger ability to reduce rice chalkiness, particularly in the environment of high temperature (HT) in the first cropping season (FCS). Our research demonstrates that by pyramiding low chalkiness QTLs, it is feasible to develop the high-quality rice varieties with low chalkiness at the best quality level even in the HT environment of FCS.

19.
Biosensors (Basel) ; 13(4)2023 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-37185558

RESUMO

Sleep apnea syndrome (SAS) is a common but underdiagnosed health problem related to impaired quality of life and increased cardiovascular risk. In order to solve the problem of complicated and expensive operation procedures for clinical diagnosis of sleep apnea, here we propose a small and low-cost wearable apnea diagnostic system. The system uses a photoplethysmography (PPG) optical sensor to collect human pulse wave signals and blood oxygen saturation synchronously. Then multiscale entropy and random forest algorithms are used to process the PPG signal for analysis and diagnosis of sleep apnea. The SAS determination is based on the comprehensive diagnosis of the PPG signal and blood oxygen saturation signal, and the blood oxygen is used to exclude the error induced by non-pathological factors. The performance of the system is compared with the Compumedics Grael PSG (Polysomnography) sleep monitoring system. This simple diagnostic system provides a feasible technical solution for portable and low-cost screening and diagnosis of SAS patients with a high accuracy of over 85%.


Assuntos
Síndromes da Apneia do Sono , Dispositivos Eletrônicos Vestíveis , Humanos , Qualidade de Vida , Síndromes da Apneia do Sono/diagnóstico , Polissonografia/métodos , Aprendizado de Máquina , Fotopletismografia/métodos
20.
Spectrochim Acta A Mol Biomol Spectrosc ; 297: 122720, 2023 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-37058840

RESUMO

Monitoring (including prediction and visualization) the gene modulated cadmium (Cd) accumulation in rice grains is one of the most important steps for identification of key transporter genes responsible for grain Cd accumulation and breeding low grain-Cd-accumulating rice cultivars. A method to predict and visualize the gene modulated ultralow Cd accumulation in brown rice grains based on the hyperspectral image (HSI) technology is proposed in this study. Firstly, the Vis-NIR HSIs of brown rice grain samples with 48Cd content levels induced by gene modulation (ranging from 0.0637 to 0.1845 mg/kg) are collected using HSI system. Then, Kernel-ridge (KRR) and random forest (RFR) regression models based on full spectral data and the data after feature dimension reduction (FDR) with kernel principal component analysis (KPCA) and truncated singular value decomposition (TSVD) algorithms are established to predict the Cd contents. RFR model shows poor performance due to the over-fitting based on the full spectral data, while the KRR model can obtain a good predict accuracy with Rp2 of 0.9035, RMSEP of 0.0037 and RPD of 3.278. After the FDR of the full spectral data, the RFR model combined with TSVD reaches the optimum prediction accuracy with Rp2 of 0.9056, RMSEP of 0.0074 and RPD of 3.318, and the best prediction precision of KRR model can also be further enhanced by TSVD with Rp2 of 0.9224, RMSEP of 0.0067 and RPD of 3.512. Finally, the visualization of the predicted Cd accumulation in brown rice grains are realized based on the best regression model (KRR + TSVD). The results of this work indicate that Vis-NIR HSI has great potential for detection and visualization gene modulation induced ultralow Cd accumulation and transport in rice crops.


Assuntos
Oryza , Poluentes do Solo , Cádmio/análise , Oryza/genética , Imageamento Hiperespectral , Poluentes do Solo/análise , Algoritmos
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