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1.
Molecules ; 26(13)2021 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-34202405

RESUMO

The bacterial leaf blight (BLB) caused by Xanthomonas oryzae pv. oryzae (Xoo) is one of the most serious rice diseases, causing huge yield losses worldwide. Several technologies and approaches have been opted to reduce the damage; however, these have had limited success. Recently, scientists have been focusing their efforts on developing efficient and environmentally friendly nanobactericides for controlling bacterial diseases in rice fields. In the present study, a scanning electron microscope (SEM), transmission electron microscope (TEM), and a confocal laser scanning microscope (CLSM) were utilized to investigate the mode of actions of ginger EOs on the cell structure of Xoo. The ginger EOs caused the cells to grow abnormally, resulting in an irregular form with hollow layers, whereas the dimethylsulfoxide (DMSO) treatment showed a typical rod shape for the Xoo cell. Ginger EOs restricted the growth and production of biofilms by reducing the number of biofilms generated as indicated by CLSM. Due to the instability, poor solubility, and durability of ginger EOs, a nanoemulsions approach was used, and a glasshouse trial was performed to assess their efficacy on BLB disease control. The in vitro antibacterial activity of the developed nanobactericides was promising at different concentration (50-125 µL/mL) tested. The efficacy was concentration-dependent. There was significant antibacterial activity recorded at higher concentrations. A glasshouse trial revealed that developed nanobactericides managed to suppress BLB disease severity effectively. Treatment at a concentration of 125 µL/mL was the best based on the suppression of disease severity index, AUDPC value, disease reduction (DR), and protection index (PI). Furthermore, findings on plant growth, physiological features, and yield parameters were significantly enhanced compared to the positive control treatment. In conclusion, the results indicated that ginger essential oils loaded-nanoemulsions are a promising alternative to synthetic antibiotics in suppressing Xoo growth, regulating the BLB disease, and enhancing rice yield under a glasshouse trial.


Assuntos
Gengibre/química , Óleos Voláteis , Oryza , Doenças das Plantas/microbiologia , Xanthomonas/crescimento & desenvolvimento , Óleos Voláteis/química , Óleos Voláteis/farmacologia , Oryza/química , Oryza/crescimento & desenvolvimento , Oryza/microbiologia , Oryza/ultraestrutura , Xanthomonas/ultraestrutura
2.
Int J Mol Sci ; 22(11)2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-34206144

RESUMO

The Casparian strip domain protein 1 (OsCASP1) is necessary for the formation of the Casparian strip (CS) in the rice endodermis. It also controls Ca2+ transport to the stele. Here, we demonstrated that OsCASP1 overexpression enhanced Ca tolerance in rice. Under normal conditions, OsCASP1-overexpressed lines showed similar concentrations of essential metals in the roots and shoots compared to the wild type, while under high Ca conditions, Ca in the roots, shoots, and xylem sap of the OsCASP1-overexpressed lines was significantly decreased. This did not apply to other essential metals. Ca-inhibited growth was significantly alleviated in the OsCASP1-overexpressed lines. Furthermore, OsCASP1 overexpression resulted in earlier formation of both the CS and functional apoplastic barrier in the endodermis but did not induce ectopic CS formation in non-endodermal cell layers and affect suberin accumulation in the endodermis. These results indicate that the overexpression of OsCASP1 promotes CS formation in endodermal cells and inhibits Ca2+ transport by the apoplastic pathway, restricting Ca accumulation in the roots and shoots under high Ca conditions. Taken together, the results suggest that OsCASP1 overexpression is an effective way to improve rice adaptation to high Ca environments.


Assuntos
Cálcio/metabolismo , Caspase 1/genética , Oryza/genética , Caspase 1/metabolismo , Parede Celular/genética , Regulação da Expressão Gênica de Plantas/genética , Oryza/crescimento & desenvolvimento , Raízes de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento
3.
Gene ; 796-797: 145806, 2021 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-34197950

RESUMO

To sustain high crop yield, a comprehensive understanding of the processes by which plants sense and acquire nutrients is of great importance. For the efficiency of crop fertilizer, it is essential to exploring the the signaling networks that coordinate the usage of nitrogen and phosphorus, the most demanding two mineral nutrients in plants. Here, we found that a protein OsCBL1 (Calcineurin B-like protein 1) is involved in the regulation of nitrogen and phosphorus signaling in rice. The nitrogen element, existing as ammonium or nitrate in the environment, affects nitrate signaling in vivo and root growth. Compared with the wild type, knockdown of OsCBL1 inhibit the growth of rice to the same extent, when nitrogen is deficient or nitrogen is present in the form of ammonium-nitrate mixture. The growth inhibition by OsCBL1-knockdown is more pronounced when nitrogen is present as ammonium. The phosphorus starvation-responsive genes is also regulated by the compound of nitrogen present in vitro and OsCBL1, while the phosphorus content is not affected. These results suggest that OsCBL1 may be involved in the response of rice to nitrogen and phosphorus nutrition in the environment, as well as the regulation of rice growth by environmental nutrition.


Assuntos
Proteínas de Ligação ao Cálcio/fisiologia , Nitratos/metabolismo , Oryza/crescimento & desenvolvimento , Fosfatos/metabolismo , Proteínas de Plantas/fisiologia , Plântula/crescimento & desenvolvimento , Proteínas de Ligação ao Cálcio/genética , Técnicas de Silenciamento de Genes , Oryza/genética , Proteínas de Plantas/genética , Plântula/genética , Transdução de Sinais
4.
Int J Mol Sci ; 22(11)2021 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-34199720

RESUMO

The underground reserve (root) has been an uncharted research territory with its untapped genetic variation yet to be exploited. Identifying ideal traits and breeding new rice varieties with efficient root system architecture (RSA) has great potential to increase resource-use efficiency and grain yield, especially under direct-seeded rice, by adapting to aerobic soil conditions. In this review, we tried to mine the available research information on the direct-seeded rice (DSR) root system to highlight the requirements of different root traits such as root architecture, length, number, density, thickness, diameter, and angle that play a pivotal role in determining the uptake of nutrients and moisture at different stages of plant growth. RSA also faces several stresses, due to excess or deficiency of moisture and nutrients, low or high temperature, or saline conditions. To counteract these hindrances, adaptation in response to stress becomes essential. Candidate genes such as early root growth enhancer PSTOL1, surface rooting QTL qSOR1, deep rooting gene DRO1, and numerous transporters for their respective nutrients and stress-responsive factors have been identified and validated under different circumstances. Identifying the desired QTLs and transporters underlying these traits and then designing an ideal root architecture can help in developing a suitable DSR cultivar and aid in further advancement in this direction.


Assuntos
Adaptação Fisiológica/fisiologia , Oryza/fisiologia , Raízes de Plantas/anatomia & histologia , Raízes de Plantas/fisiologia , Sementes/fisiologia , Germinação/fisiologia , Oryza/genética , Oryza/crescimento & desenvolvimento , Locos de Características Quantitativas/genética , Sementes/genética , Sementes/crescimento & desenvolvimento
5.
BMC Plant Biol ; 21(1): 278, 2021 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-34147069

RESUMO

BACKGROUND: Cold stress caused by low temperatures is an important factor restricting rice production. Identification of cold-tolerance genes that can stably express in cold environments is crucial for molecular rice breeding. RESULTS: In this study, we employed high-throughput quantitative trait locus sequencing (QTL-seq) analyses in a 460-individual F2:3 mapping population to identify major QTL genomic regions governing cold tolerance at the seedling stage in rice. A novel major QTL (qCTS6) controlling the survival rate (SR) under low-temperature conditions of 9°C/10 days was mapped on the 2.60-Mb interval on chromosome 6. Twenty-seven single-nucleotide polymorphism (SNP) markers were designed for the qCST6 region based on re-sequencing data, and local QTL mapping was conducted using traditional linkage analysis. Eventually, we mapped qCTS6 to a 96.6-kb region containing 13 annotated genes, of which seven predicted genes contained 13 non-synonymous SNP loci. Quantitative reverse transcription PCR analysis revealed that only Os06g0719500, an OsbZIP54 transcription factor, was strongly induced by cold stress. Haplotype analysis confirmed that +376 bp (T>A) in the OsbZIP54 coding region played a key role in regulating cold tolerance in rice. CONCLUSION: We identified OsbZIP54 as a novel regulatory gene associated with rice cold-responsive traits, with its Dongfu-104 allele showing specific cold-induction expression serving as an important molecular variation for rice improvement. This result is expected to further exploration of the genetic mechanism of rice cold tolerance at the seedling stage and improve cold tolerance in rice varieties by marker-assisted selection.


Assuntos
Aclimatação/genética , Genes de Plantas , Oryza/genética , Mapeamento Cromossômico , Oryza/crescimento & desenvolvimento , Oryza/fisiologia , Polimorfismo de Nucleotídeo Único , Locos de Características Quantitativas , Plântula/genética , Plântula/fisiologia , Sequenciamento Completo do Genoma
6.
BMC Plant Biol ; 21(1): 282, 2021 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-34154533

RESUMO

BACKGROUND: Phosphorus (P), being one of the essential components of nucleic acids, cell membranes and enzymes, indispensable for diverse cellular processes like photosynthesis/carbohydrate metabolism, energy production, redox homeostasis and signaling. Crop yield is severely affected due to Phosphate (Pi) deficiency; and to cope with Pi-deficiency, plants have evolved several strategies. Some rice genotypes are compatible with low Pi availability, whereas others are sensitive to Pi deficiency. However, the underlying molecular mechanism for low Pi tolerance remains largely unexplored. RESULT: Several studies were carried out to understand Pi-deficiency responses in rice at seedling stage, but few of them targeted molecular aspects/responses of Pi-starvation at the advanced stage of growth. To delineate the molecular mechanisms for low Pi tolerance, a pair of contrasting rice (Oryza sativa L.) genotypes [viz. Pusa-44 (Pi-deficiency sensitive) and its near isogenic line (NIL-23, Pi-deficiency tolerant) harboring Phosphorus uptake 1 (Pup1) QTL from an aus landrace Kasalath] were used. Comparative morphological, physiological, and biochemical analyses confirmed some of the well-known findings. Transcriptome analysis of shoot and root tissues from 45-day-old rice plants grown hydroponically under P-sufficient (16 ppm Pi) or P-starved (0 ppm Pi) medium revealed that Pi-starvation stress causes global transcriptional reprogramming affecting several transcription factors, signaling pathways and other regulatory genes. We could identify several significantly up-regulated genes in roots of NIL-23 under Pi-starvation which might be responsible for the Pi starvation tolerance. Pathway enrichment analysis indicated significant role of certain phosphatases, transporters, transcription factors, carbohydrate metabolism, hormone-signaling, and epigenetic processes in improving P-starvation stress tolerance in NIL-23. CONCLUSION: We report the important candidate mechanisms for Pi acquisition/solubilization, recycling, remobilization/transport, sensing/signalling, genetic/epigenetic regulation, and cell wall structural changes to be responsible for P-starvation tolerance in NIL-23. The study provides some of the novel information useful for improving phosphorus-use efficiency in rice cultivars.


Assuntos
Adaptação Fisiológica , Oryza/genética , Oryza/metabolismo , Fósforo/metabolismo , Fosfatase Ácida/metabolismo , Epigênese Genética , Genes de Plantas , Genótipo , Oryza/crescimento & desenvolvimento , Reguladores de Crescimento de Plantas/metabolismo , Folhas de Planta/metabolismo , Raízes de Plantas/metabolismo , Locos de Características Quantitativas , Plântula/crescimento & desenvolvimento , Transdução de Sinais , Fatores de Transcrição/metabolismo , Transcriptoma
7.
Ecotoxicol Environ Saf ; 220: 112404, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34111660

RESUMO

Cadmium (Cd), chromium (Cr), lead (Pb), mercury (Hg) and arsenic (As) are potent toxicants to human health via dietary intake. It is imperative to establish accurate soil thresholds based on soil-plant transfer models and food safety standards for safe agricultural production. This study takes rice genotypes and soil properties into account to derive soil thresholds for five heavy metal(loid)s using the bioconcentration factors (BCF) and species sensitivity distribution (SSD) based on the food safety standard. The BCF generated from two paddy soils was calculated to investigate the sensitivity of heavy metal accumulation in nine rice cultivars in a greenhouse pot experiment. Then, empirical soil-plant transfer models were developed from a middle-sensitivity rice cultivar (Denong 2000, one selected from nine rice) grown in nineteen paddy soils with various soil properties under a proper exogenously metal(loid)s concentration gradient. After normalization, hazardous concentrations from the fifth percentile (HC5) were calculated from the SSD curves, and the derived soil thresholds were obtained from HC5 prediction models that based on the combination of pH and organic carbon (OC) or cation exchange capacity (CEC). The soil Cd threshold derived based on pH and organic carbon (pH < 7.5, OC ≥ 20 g kg-1) was 1.3-fold of those only considering pH, whereas the Pb threshold (pH > 6, CEC ≥ 20 cmolc kg-1) was 3.1 times lower than the current threshold. The derived thresholds for five elements were validated to be reliable through literature data and field experiments. The results suggested that deriving soil heavy metal(loid)s threshold using SSD method and local food safety standards is feasible and also applicable to other crops as well as other regions with potential health risks of toxic elements contamination in agricultural production.


Assuntos
Metais Pesados/normas , Oryza/crescimento & desenvolvimento , Poluentes do Solo/normas , Solo/normas , Arsênio/análise , Arsênio/normas , Cádmio/análise , Cádmio/normas , Cromo/análise , Cromo/normas , Produtos Agrícolas/crescimento & desenvolvimento , Produtos Agrícolas/normas , Inocuidade dos Alimentos , Humanos , Chumbo/análise , Chumbo/normas , Mercúrio/análise , Mercúrio/normas , Metais Pesados/análise , Oryza/química , Oryza/genética , Solo/química , Poluentes do Solo/análise
8.
Ecotoxicol Environ Saf ; 220: 112401, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34118747

RESUMO

Cadmium (Cd) is a trace element causing severe toxicity symptoms in plants, besides posing hazardous fitness issue due to its buildup in the human body through food chain. Nanoparticles (NPs) are recently employed as a novel strategy to directly ameliorate the Cd stress and acted as nano-fertilizers. The intend of the current study was to explore the effects of zinc oxide nanoparticles (ZnO-NPs; 50 mg/L) on plant growth, photosynthetic activity, elemental status and antioxidant activity in Oryza sativa (rice) under Cd (0.8 mM) stress. To this end, the rice plants are treated by Cd stress at 15 days after sowing (DAS), and the treatment was given directly into the soil. Supply of ZnO-NPs as foliar spray was given for five consecutive days from 30 to 35 DAS, and sampling was done at 45 DAS. However, rice plants supplemented with ZnO-NPs under the Cd toxicity revealed significantly increased shoot length (SL; 34.0%), root fresh weight (RFW; 30.0%), shoot dry weight (SDW; 23.07%), and root dry weight (RDW; 12.24%). Moreover, the ZnO-NPs supplement has also positive effects on photosynthesis related parameters, SPAD value (40%), chloroplast structure, and qualitatively high fluorescence observed by confocal microscopy even under Cd stress. ZnO-NPs also substantially prevented the increases of hydrogen peroxide (H2O2) and malondialdehyde (MDA) triggered by Cd. Physiological and biochemical analysis showed that ZnO-NPs increased enzymatic activities of superoxide dismutase (SOD; 59%), catalase (CAT; 52%), and proline (17%) that metabolize reactive oxygen species (ROS); these increases coincided with the changes observed in the H2O2 and MDA accumulation after ZnO-NPs application. In conclusion, ZnO-NPs application to foliage has great efficiency to improve biomass, photosynthesis, protein, antioxidant enzymes activity, mineral nutrient contents and reducing Cd levels in rice. This can be attributed mainly from reduced oxidative damage resulted due to the ZnO-NPs application.


Assuntos
Antioxidantes/metabolismo , Cádmio/efeitos adversos , Nanopartículas , Oryza/efeitos dos fármacos , Fotossíntese/efeitos dos fármacos , Poluentes do Solo/efeitos adversos , Óxido de Zinco/farmacologia , Biomassa , Catalase/metabolismo , Produtos Agrícolas/efeitos adversos , Produtos Agrícolas/fisiologia , Fertilizantes , Humanos , Peróxido de Hidrogênio/metabolismo , Malondialdeído/metabolismo , Oryza/crescimento & desenvolvimento , Oryza/metabolismo , Oryza/fisiologia , Estresse Oxidativo/efeitos dos fármacos , Folhas de Planta , Solo/química , Superóxido Dismutase/metabolismo , Óxido de Zinco/administração & dosagem
9.
BMC Plant Biol ; 21(1): 298, 2021 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-34187351

RESUMO

BACKGROUND: Awn of rice is an important domestication trait closely associated with yield traits. Therefore, the identification of genes for awn development is of great significance for the elucidation of molecular mechanism of awn development and the genetic improvement of yield traits in rice. RESULTS: In this study, using chromosome segment substitution lines (CSSLs) derived from a long-awned Guangxi common wild rice (GXCWR, Oryza rufipogon Griff.) and a short-awned indica cultivar 9311, we identified An-4, a potential quantitative trait locus (QTL) for awn development. Then, An-4 was fine mapped into a 56-kb region of chromosome 2, which contained four annotated genes. Among these four annotated genes, Os02g0594800 was concluded to be the potential candidate gene for An-4. An-4 exhibited pleiotropic effects on awn development and several yield traits. Scanning electron microscopy (SEM) analysis showed that An-4 significantly promoted awn development at Sp7 and Sp8 stage of spikelet development. Transcriptome analysis suggested that An-4 might influence the development of awn by regulating the expression of genes related to growth, developmental process, channel regulation and extracellular region. By contrast to those of 9311, the expression level of OsRR5 in CSSL128 was significantly down-regulated, whereas the expression levels of OsCKX2 and OsGA2ox5 in CSSL128 were significantly up-regulated. In addition, our study showed that An-4 had additive effects with other genes for awn development, such as An-1, An-2/LABA1 and An-3/GAD1/RAE2. CONCLUSIONS: The identification of An-4 lays a foundation for cloning of An-4 and further elucidation of the molecular mechanism of awn development. Moreover, the identification of favorable allelic variation of An-4 from 9311 will be useful to improve rice yield traits.


Assuntos
Genes de Plantas/genética , Oryza/crescimento & desenvolvimento , Componentes Aéreos da Planta/crescimento & desenvolvimento , Locos de Características Quantitativas/genética , Mapeamento Cromossômico , Cromossomos de Plantas/genética , Perfilação da Expressão Gênica , Genes de Plantas/fisiologia , Microscopia Eletrônica de Varredura , Oryza/genética , Componentes Aéreos da Planta/genética , Característica Quantitativa Herdável
10.
Int J Mol Sci ; 22(9)2021 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-34063649

RESUMO

The waxy (Wx) gene, encoding the granule-bound starch synthase (GBSS), is responsible for amylose biosynthesis and plays a crucial role in defining eating and cooking quality. The waxy locus controls both the non-waxy and waxy rice phenotypes. Rice starch can be altered into various forms by either reducing or increasing the amylose content, depending on consumer preference and region. Low-amylose rice is preferred by consumers because of its softness and sticky appearance. A better way of improving crops other than downregulation and overexpression of a gene or genes may be achieved through the posttranslational modification of sites or regulatory enzymes that regulate them because of their significance. The impact of posttranslational GBSSI modifications on extra-long unit chains (ELCs) remains largely unknown. Numerous studies have been reported on different crops, such as wheat, maize, and barley, but the rice starch granule proteome remains largely unknown. There is a need to improve the yield of low-amylose rice by employing posttranslational modification of Wx, since the market demand is increasing every day in order to meet the market demand for low-amylose rice in the regional area that prefers low-amylose rice, particularly in China. In this review, we have conducted an in-depth review of waxy rice, starch properties, starch biosynthesis, and posttranslational modification of waxy protein to genetically improve starch quality in rice grains.


Assuntos
Amilose/genética , Oryza/genética , Proteínas de Plantas/genética , Sintase do Amido/genética , Grão Comestível/genética , Grão Comestível/crescimento & desenvolvimento , Regulação da Expressão Gênica de Plantas/genética , Oryza/crescimento & desenvolvimento , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/crescimento & desenvolvimento , Processamento de Proteína Pós-Traducional/genética , Amido/genética
11.
Gene ; 792: 145742, 2021 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-34051336

RESUMO

Given the complexity of nutrient stress responses and the availability of a few validated reference genes, we aimed to identify robust and stable reference genes for macronutrient stress in rice and soybean. Ten potential reference genes were evaluated using geNorm, NormFinder, BestKeeper, Comparative ΔCt method, and RefFinder algorithms under low and completely starved conditions of nitrogen (N), phosphorus (P), potassium (K), and sulphur (S). Results revealed distinct sets of reference gene pairs, showing stable expression under different experimental conditions. The gene pairs TIP41/UBC(9/10/18) and F-box/UBC10 were most stable in rice and soybean, respectively under N stress. Under P stress, UBC9/UBC10 in rice and F-Box/UBC10 in soybean were most stable. Similarly, TIP41/UBC10 in rice and RING FINGER/UBC9 in soybean were the best gene pairs under K stress while F-Box/TIP41 in rice and UBC9/UBC10 in soybean were the most stable gene pairs under S stress. These reference gene pairs were validated by quantifying the expression levels of high-affinity transporters like NRT2.1/NRT2.5, PT1, AKT1, and SULTR1 for N, P, K, and S stress, respectively. This study reiterates the importance of choosing reference genes based on crop species and the experimental conditions, in order to obtain concrete answers to missing links of gene regulation in response to macronutrient deficiencies.


Assuntos
Regulação da Expressão Gênica de Plantas , Genes Essenciais , Oryza/genética , Proteínas de Plantas/genética , Soja/genética , Estresse Fisiológico/genética , Perfilação da Expressão Gênica , Hidroponia/métodos , Nitrogênio/deficiência , Nitrogênio/farmacologia , Oryza/efeitos dos fármacos , Oryza/crescimento & desenvolvimento , Oryza/metabolismo , Fósforo/deficiência , Fósforo/farmacologia , Proteínas de Plantas/classificação , Proteínas de Plantas/metabolismo , Potássio/farmacologia , Deficiência de Potássio/metabolismo , Padrões de Referência , Plântula/efeitos dos fármacos , Plântula/genética , Plântula/crescimento & desenvolvimento , Plântula/metabolismo , Soja/efeitos dos fármacos , Soja/crescimento & desenvolvimento , Soja/metabolismo , Enxofre/deficiência , Enxofre/farmacologia
12.
Ecotoxicol Environ Saf ; 217: 112100, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-33933890

RESUMO

Studies focusing on arsenic methylation and volatilization in paddy soil, aiming to limit bioaccumulation of arsenic (As) in rice grains, have attracted global attention. In this study, we explored three aspects of these topics. First, rainwater and trace H2O2 were compared for their influence on the arsenic methylation and volatilization of paddy soil in different rice growth stages. Second, the arsenic accumulation in different parts of rice was affected by rainwater and trace H2O2. Third, we determined whether rice fields were affected by rainwater and trace H2O2. The result showed that the rainwater or trace H2O2 irrigation caused As(III) to significantly decrease and As(V) to significantly increase in soil. A similar consequence occurred in the filling stage and mature stage of rice. The arsenic volatilization rates of the rainwater and trace H2O2 irrigation were significantly higher than the control, and the arsenic volatilization of rainwater irrigation was the highest (51.0 µg m-2 d-1) in the filling stage. Compared to the control, the total arsenic and iAs of treatments decreased by 14-41% and 12-32% respectively. Finally, we found that rainwater and trace H2O2 irrigation likely increased rice fields.


Assuntos
Poluentes Atmosféricos/química , Arsênio/toxicidade , Peróxido de Hidrogênio/química , Oryza/fisiologia , Poluentes do Solo/toxicidade , Arsênio/química , Arsênio/metabolismo , Metilação , Oryza/crescimento & desenvolvimento , Solo , Poluentes do Solo/análise , Poluentes do Solo/química , Poluentes do Solo/metabolismo , Volatilização
13.
BMC Plant Biol ; 21(1): 211, 2021 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-33975546

RESUMO

BACKGROUND: Nitrogen (N) is an important nutrient for plant growth, development, and agricultural production. Nitrogen stress could induce epigenetic changes in plants. In our research, overexpression of the OsNAR2.1 line was used as a testing target in rice plants with high nitrogen-use efficiency to study the changes of rice methylation and growth in respond of the endogenous and external nitrogen stress. RESULTS: Our results showed that external N deficiency could decrease seed N content and plant growth of the overexpression line. During the filial growth, we found that the low parent seed nitrogen (LPSN) in the overexpression line could lead to a decrease in the filial seed nitrogen content, total plant nitrogen content, yield, and OsNAR2.1 expression (28, 35, 23, and 55%, respectively) compared with high parent seed nitrogen (HPSN) in high nitrogen external supply. However, such decreases were not observed in wild type. Furthermore, methylation sequencing results showed that LPSN caused massive gene methylation changes, which enriched in over 20 GO pathways in the filial overexpression line, and the expression of OsNAR2.1 in LPSN filial overexpression plants was significantly reduced compared to HPSN filial plants in high external N, which was not shown in wild type. CONCLUSIONS: We suggest that the parent seed nitrogen content decreased induced DNA methylation changes at the epigenetic level and significantly decreased the expression of OsNAR2.1, resulting in a heritable phenotype of N deficiency over two generations of the overexpression line.


Assuntos
Metilação de DNA , Nitrogênio/análise , Oryza/crescimento & desenvolvimento , Oryza/genética , Oryza/metabolismo , Sementes/química , Sementes/metabolismo , Produtos Agrícolas/genética , Produtos Agrícolas/crescimento & desenvolvimento , Produtos Agrícolas/metabolismo , DNA de Plantas , Regulação da Expressão Gênica de Plantas , Variação Genética , Genótipo , Plantas Geneticamente Modificadas
14.
BMC Plant Biol ; 21(1): 233, 2021 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-34034675

RESUMO

BACKGROUND: Lanthanum (La) is a rare earth element that can influence plant growth and development. However, the effect of La on growth, yield formation and 2-acetyl-1-pyrroline (2-AP, a key compound responsible for the aroma of rice) biosynthesis in aromatic rice (Oryza sativa L. subsp. japonica Kato) has not been reported. Therefore, the present study investigated the effects of La on growth, photosynthesis, yield formation and 2-AP biosynthesis in aromatic rice through three experiments. RESULTS: Two pot experiments and a two-year field trial were conducted with different rates of La application (20-120 LaCl3 mg kg-1 and 12 kg ha-1 LaCl3), and treatments without La application were used as controls. The results showed that the application of LaCl3 at 80 and 100 mg kg-1 and at 12 kg ha-1 greatly increased the 2-AP content (by 6.45-43.03%) in aromatic rice seedlings and mature grains compared with the control. The La treatments also increased the chlorophyll content, net photosynthetic rate and total aboveground biomass of rice seedlings. Higher antioxidant enzyme (superoxide, peroxidase, and catalase) activity was detected in the La treatments than in the control. The La treatments also increased the grain yield, grain number per panicle and seed-setting rate of aromatic rice relative to the control. Moreover, the grain proline and γ-aminobutyric acid contents and the activity of betaine aldehyde dehydrogenase significantly decreased under the La treatment. The application of La to soil enhanced the activity of proline dehydrogenase by 20.62-56.95%. CONCLUSIONS: La improved the growth, yield formation and 2-AP content of aromatic rice and enhanced 2-AP biosynthesis by increasing the conversion of proline to 2-AP and decreasing the conversion of GABald to GABA.


Assuntos
Antioxidantes/metabolismo , Lantânio/farmacologia , Oryza/fisiologia , Proteínas de Plantas/metabolismo , Pirróis/metabolismo , Clorofila/metabolismo , Grão Comestível , Oryza/genética , Oryza/crescimento & desenvolvimento , Fotossíntese , Proteínas de Plantas/genética , Prolina/metabolismo , Prolina Oxidase/genética , Prolina Oxidase/metabolismo , Sementes/genética , Sementes/crescimento & desenvolvimento , Sementes/fisiologia
15.
Plant Sci ; 307: 110907, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33902846

RESUMO

Chloroplasts are closely associated with the growth and development of higher plants. Accumulating evidence has revealed that the multiple organellar RNA editing factors (MORF) family of proteins influences plastidic and mitochondrial development through post-transcriptional regulation. However, the role of MORFs in regulating the development of chloroplasts in rice is still unclear. The OsMORF9 gene belongs to a small family of 7 genes in rice and is highly expressed in young leaves. We used the CRISPR/Cas9 system to mutate OsMORF9. The resulting knockout lines osmorf9-1 and osmorf9-2 exhibited an albino seedling lethal phenotype. Besides, the expression of many plastid-encoded genes involved in photosynthesis, the biogenesis of plastidic ribosomes and the editing and splicing of specific plastidic RNA molecules were severely affected in these two OsMORF9 mutants. Furthermore, yeast two-hybrid analysis revealed that OsMORF9 could interact with OsSLA4 and DUA1 which are members of the pentatricopeptide repeat (PPR) family of proteins. Analysis of subcellular localization of OsMORF9 also suggested that it might function in chloroplasts. The findings from the present study demonstrated the critical role of OsMORF9 in the biogenesis of chloroplast ribosomes, chloroplast development and seedling survival. This therefore provides new insights on the function of MORF proteins in rice.


Assuntos
Cloroplastos/fisiologia , Oryza/crescimento & desenvolvimento , Oryza/genética , Edição de RNA , RNA de Plantas , Plântula/crescimento & desenvolvimento , Plântula/genética , Cloroplastos/genética , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Fenótipo
16.
Molecules ; 26(8)2021 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-33920363

RESUMO

As one of the common abiotic stresses, chilling stress has negative effects on rice growth and development. Minimization of these adverse effects through various ways is vital for the productivity of rice. Nanoparticles (NPs) serve as one of the effective alleviation methods against abiotic stresses. In our research, zinc oxide (ZnO) NPs were utilized as foliar sprays on rice leaves to explore the mechanism underlying the effect of NPs against the negative impact of chilling stress on rice seedlings. We revealed that foliar application of ZnO NPs significantly alleviated chilling stress in hydroponically grown rice seedlings, including improved plant height, root length, and dry biomass. Besides, ZnO NPs also restored chlorophyll accumulation and significantly ameliorated chilling-induced oxidative stress with reduced levels of H2O2, MDA, proline, and increased activities of major antioxidative enzymes, superoxide dismutase (SOD), catalase (CAT), and peroxidase (POD). We further found that foliar application of ZnO NPs induced the chilling-induced gene expression of the antioxidative system (OsCu/ZnSOD1, OsCu/ZnSOD2, OsCu/ZnSOD3, OsPRX11, OsPRX65, OsPRX89, OsCATA, and OsCATB) and chilling response transcription factors (OsbZIP52, OsMYB4, OsMYB30, OsNAC5, OsWRKY76, and OsWRKY94) in leaves of chilling-treated seedlings. Taken together, our results suggest that foliar application of ZnO NPs could alleviate chilling stress in rice via the mediation of the antioxidative system and chilling response transcription factors.


Assuntos
Antioxidantes/farmacologia , Clorofila/biossíntese , Nanopartículas/química , Oryza/efeitos dos fármacos , Fatores de Transcrição/genética , Óxido de Zinco/farmacologia , Catalase/genética , Catalase/metabolismo , Clorofila/agonistas , Temperatura Baixa , Regulação da Expressão Gênica de Plantas , Hidroponia/métodos , Malondialdeído/metabolismo , Nanopartículas/ultraestrutura , Oryza/genética , Oryza/crescimento & desenvolvimento , Oryza/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Peroxidase/genética , Peroxidase/metabolismo , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/genética , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Prolina/metabolismo , Espécies Reativas de Oxigênio/antagonistas & inibidores , Espécies Reativas de Oxigênio/metabolismo , Plântula/efeitos dos fármacos , Plântula/genética , Plântula/crescimento & desenvolvimento , Plântula/metabolismo , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismo , Fatores de Transcrição/agonistas , Fatores de Transcrição/metabolismo
17.
Int J Mol Sci ; 22(9)2021 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-33923150

RESUMO

Tolerance of anaerobic germination (AG) is a key trait in the development of direct seeded rice. Through rapid and sustained coleoptile elongation, AG tolerance enables robust seedling establishment under flooded conditions. Previous attempts to fine map and characterize AG2 (qAG7.1), a major centromere-spanning AG tolerance QTL, derived from the indica variety Ma-Zhan Red, have failed. Here, a novel approach of "enriched haplotype" genome-wide association study based on the Ma-Zhan Red haplotype in the AG2 region was successfully used to narrow down AG2 from more than 7 Mb to less than 0.7 Mb. The AG2 peak region contained 27 genes, including the Rc gene, responsible for red pericarp development in pigmented rice. Through comparative variant and transcriptome analysis between AG tolerant donors and susceptible accessions several candidate genes potentially controlling AG2 were identified, among them several regulatory genes. Genome-wide comparative transcriptome analysis suggested differential regulation of sugar metabolism, particularly trehalose metabolism, as well as differential regulation of cell wall modification and chloroplast development to be implicated in AG tolerance mechanisms.


Assuntos
Cromossomos de Plantas/genética , Estudo de Associação Genômica Ampla , Germinação , Oryza/genética , Proteínas de Plantas/metabolismo , Polimorfismo de Nucleotídeo Único , Locos de Características Quantitativas , Anaerobiose , Mapeamento Cromossômico , Perfilação da Expressão Gênica , Oryza/crescimento & desenvolvimento , Proteínas de Plantas/genética
18.
Int J Mol Sci ; 22(8)2021 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-33920962

RESUMO

The plant hormone auxin acts as a mediator providing positional instructions in a range of developmental processes. Studies in Arabidopsis thaliana L. show that auxin acts in large part via activation of Auxin Response Factors (ARFs) that in turn regulate the expression of downstream genes. The rice (Oryza sativa L.) gene OsARF11 is of interest because of its expression in developing rice organs and its high sequence similarity with MONOPTEROS/ARF5, a gene with prominent roles in A. thaliana development. We have assessed the phenotype of homozygous insertion mutants in the OsARF11 gene and found that in relation to wildtype, osarf11 seedlings produced fewer and shorter roots as well as shorter and less wide leaves. Leaves developed fewer veins and larger areoles. Mature osarf11 plants had a reduced root system, fewer branches per panicle, fewer grains per panicle and fewer filled seeds. Mutants had a reduced sensitivity to auxin-mediated callus formation and inhibition of root elongation, and phenylboronic acid (PBA)-mediated inhibition of vein formation. Taken together, our results implicate OsARF11 in auxin-mediated growth of multiple organs and leaf veins. OsARF11 also appears to play a central role in the formation of lateral root, panicle branch, and grain meristems.


Assuntos
Meristema/crescimento & desenvolvimento , Oryza/crescimento & desenvolvimento , Oryza/metabolismo , Desenvolvimento Vegetal , Proteínas de Plantas/metabolismo , Feixe Vascular de Plantas/crescimento & desenvolvimento , Sementes/crescimento & desenvolvimento , Ácidos Borônicos/farmacologia , Gravitropismo/efeitos dos fármacos , Ácidos Indolacéticos/metabolismo , Mutação/genética , Tamanho do Órgão , Oryza/genética , Fenótipo , Feixe Vascular de Plantas/metabolismo , Plântula/metabolismo
19.
Int J Mol Sci ; 22(5)2021 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-33801226

RESUMO

Ubiquitination is an important environmental stress response, and E3 ubiquitin ligases play a major role in the process. T-DNA insertion mutants of rice, Oscbe1-1, and Oscbe1-2, were identified through the screening of cold stress tolerance at seedling stage. Oscbe1 mutants showed a significantly higher cold stress tolerance in the fresh weight, chlorophyll content, and photosynthetic efficiency than wild type. Molecular prediction showed that OsCBE1 (Oryza sativa Cullin4-Based E3 ubiquitin ligase1) encoded a novel substrate receptor of Cullin4-based E3 ubiquitin ligase complex (C4E3). Whereas Oscbe1 mutants had fewer panicles and grains than wild type in the paddy field, the overexpression lines of OsCBE1 had more panicles and grains, suggesting that OsCBE1 is involved in the regulation of both abiotic stress response and development. Oscbe1 mutants also showed ABA hypersensitivity during seed germination, suggesting OsCBE1 function for the stress response via ABA signaling. In silico analysis of OsCBE1 activity predicted a CCCH-type transcription factor, OsC3H32, as a putative substrate. Co-IP (Co-immunoprecipitation) study showed that OsCBE1 interacts with OsDDB1, an expected binding component of OsCBE1 and OsC3H32. Additionally, expression of OsOLE16, OsOLE18, and OsBURP5 were negatively related with expression of OsCBE1. These results suggest that OsCBE1 functions as a regulator of the abiotic stress response via CCCH as a member of the C4E3.


Assuntos
Proteínas Culina/metabolismo , Regulação da Expressão Gênica de Plantas , Oryza/metabolismo , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/metabolismo , Estresse Fisiológico/genética , Ubiquitina-Proteína Ligases/metabolismo , Proteínas Culina/genética , Oryza/genética , Oryza/crescimento & desenvolvimento , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/crescimento & desenvolvimento , Ubiquitina/metabolismo , Ubiquitina-Proteína Ligases/genética , Ubiquitinação
20.
Int J Mol Sci ; 22(7)2021 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-33805287

RESUMO

Flowering plants develop new organs throughout their life cycle. The vegetative shoot apical meristem (SAM) generates leaf whorls, branches and stems, whereas the reproductive SAM, called the inflorescence meristem (IM), forms florets arranged on a stem or an axis. In cereal crops, the inflorescence producing grains from fertilized florets makes the major yield contribution, which is determined by the numbers and structures of branches, spikelets and florets within the inflorescence. The developmental progression largely depends on the activity of IM. The proper regulations of IM size, specification and termination are outcomes of complex interactions between promoting and restricting factors/signals. Here, we focus on recent advances in molecular mechanisms underlying potential pathways of IM identification, maintenance and differentiation in cereal crops, including rice (Oryza sativa), maize (Zea mays), wheat (Triticum aestivum), and barley (Hordeum vulgare), highlighting the researches that have facilitated grain yield by, for example, modifying the number of inflorescence branches. Combinatorial functions of key regulators and crosstalk in IM determinacy and specification are summarized. This review delivers the knowledge to crop breeding applications aiming to the improvements in yield performance and productivity.


Assuntos
Grão Comestível , Inflorescência/genética , Meristema/genética , Poaceae/metabolismo , Transdução de Sinais , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Hordeum/genética , Hordeum/crescimento & desenvolvimento , Hordeum/metabolismo , Inflorescência/anatomia & histologia , Inflorescência/crescimento & desenvolvimento , Inflorescência/metabolismo , Meristema/crescimento & desenvolvimento , Meristema/metabolismo , Meristema/fisiologia , Oryza/genética , Oryza/crescimento & desenvolvimento , Oryza/metabolismo , Poaceae/genética , Poaceae/crescimento & desenvolvimento , Triticum/genética , Triticum/crescimento & desenvolvimento , Triticum/metabolismo , Zea mays/genética , Zea mays/crescimento & desenvolvimento , Zea mays/metabolismo
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