RESUMEN
BACKGROUND: Phytochrome-interacting factors (PIFs) plays an important role in plants as hubs for intracellular signaling regulation. The PIF gene family has been identified and characterized in many plants, but alfalfa (Medicago sativa L.), an important perennial high-quality legume forage, has not been reported on the PIF gene family. RESULTS: In this study, we presented the identification and characterization of five MsPIF genes in alfalfa (Medicago sativa L.). Phylogenetic analysis indicated that PIFs from alfalfa and other four plant species could be divided into three groups supported by similar motif analysis. The collinearity analysis of the MsPIF gene family showed the presence of two gene pairs, and the collinearity analysis with AtPIFs showed three gene pairs, indicating that the evolutionary process of this family is relatively conservative. Analysis of cis-acting elements in promoter regions of MsPIF genes indicated that various elements were related to light, abiotic stress, and plant hormone responsiveness. Gene expression analyses demonstrated that MsPIFs were primarily expressed in the leaves and were induced by various abiotic stresses. CONCLUSION: This study conducted genome-wide identification, evolution, synteny analysis, and expression analysis of the PIFs in alfalfa. Our study lays a foundation for the study of the biological functions of the PIF gene family and provides a useful reference for improving abiotic stress resistance in alfalfa.
Asunto(s)
Regulación de la Expresión Génica de las Plantas , Medicago sativa , Familia de Multigenes , Filogenia , Proteínas de Plantas , Estrés Fisiológico , Medicago sativa/genética , Estrés Fisiológico/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Genoma de Planta , Regiones Promotoras Genéticas/genética , Perfilación de la Expresión GénicaRESUMEN
BACKGROUND: In alfalfa (Medicago sativa), the coexistence of interfertile subspecies (i.e. sativa, falcata and coerulea) characterized by different ploidy levels (diploidy and tetraploidy) and the occurrence of meiotic mutants capable of producing unreduced (2n) gametes, have been efficiently combined for the establishment of new polyploids. The wealth of agronomic data concerning forage quality and yield provides a thorough insight into the practical benefits of polyploidization. However, many of the underlying molecular mechanisms regarding gene expression and regulation remained completely unexplored. In this study, we aimed to address this gap by examining the transcriptome profiles of leaves and reproductive tissues, corresponding to anthers and pistils, sampled at different time points from diploid and tetraploid Medicago sativa individuals belonging to progenies produced by bilateral sexual polyploidization (dBSP and tBSP, respectively) and tetraploid individuals stemmed from unilateral sexual polyploidization (tUSP). RESULTS: Considering the crucial role played by anthers and pistils in the reduced and unreduced gametes formation, we firstly analyzed the transcriptional profiles of the reproductive tissues at different stages, regardless of the ploidy level and the origin of the samples. By using and combining three different analytical methodologies, namely weighted-gene co-expression network analysis (WGCNA), tau (τ) analysis, and differentially expressed genes (DEGs) analysis, we identified a robust set of genes and transcription factors potentially involved in both male sporogenesis and gametogenesis processes, particularly in crossing-over, callose synthesis, and exine formation. Subsequently, we assessed at the same floral stage, the differences attributable to the ploidy level (tBSP vs. dBSP) or the origin (tBSP vs. tUSP) of the samples, leading to the identification of ploidy and parent-specific genes. In this way, we identified, for example, genes that are specifically upregulated and downregulated in flower buds in the comparison between tBSP and dBSP, which could explain the reduced fertility of the former compared to the latter materials. CONCLUSIONS: While this study primarily functions as an extensive investigation at the transcriptomic level, the data provided could represent not only a valuable original asset for the scientific community but also a fully exploitable genomic resource for functional analyses in alfalfa.
Asunto(s)
Medicago sativa , RNA-Seq , Medicago sativa/genética , Transcriptoma , Ploidias , Regulación de la Expresión Génica de las Plantas , Genes de Plantas , Reproducción/genética , Flores/genética , Flores/crecimiento & desarrollo , Perfilación de la Expresión GénicaRESUMEN
Crop height and biomass are the two important phenotyping traits to screen forage population types at local and regional scales. This study aims to compare the performances of multispectral and RGB sensors onboard drones for quantitative retrievals of forage crop height and biomass at very high resolution. We acquired the unmanned aerial vehicle (UAV) multispectral images (MSIs) at 1.67 cm spatial resolution and visible data (RGB) at 0.31 cm resolution and measured the forage height and above-ground biomass over the alfalfa (Medicago sativa L.) breeding trials in the Canadian Prairies. (1) For height estimation, the digital surface model (DSM) and digital terrain model (DTM) were extracted from MSI and RGB data, respectively. As the resolution of the DTM is five times less than that of the DSM, we applied an aggregation algorithm to the DSM to constrain the same spatial resolution between DSM and DTM. The difference between DSM and DTM was computed as the canopy height model (CHM), which was at 8.35 cm and 1.55 cm for MSI and RGB data, respectively. (2) For biomass estimation, the normalized difference vegetation index (NDVI) from MSI data and excess green (ExG) index from RGB data were analyzed and regressed in terms of ground measurements, leading to empirical models. The results indicate better performance of MSI for above-ground biomass (AGB) retrievals at 1.67 cm resolution and better performance of RGB data for canopy height retrievals at 1.55 cm. Although the retrieved height was well correlated with the ground measurements, a significant underestimation was observed. Thus, we developed a bias correction function to match the retrieval with the ground measurements. This study provides insight into the optimal selection of sensor for specific targeted vegetation growth traits in a forage crop.
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Biomasa , Algoritmos , Dispositivos Aéreos No Tripulados , Medicago sativa/crecimiento & desarrollo , Productos Agrícolas/crecimiento & desarrolloRESUMEN
Drought stress is a predominant abiotic factor leading to decreased alfalfa yield. Genomic ploidy differences contribute to varying adaptation mechanisms of different alfalfa cultivars to drought conditions. This study employed a multi-omics approach to characterize the molecular basis of drought tolerance in a tetraploid variant of alfalfa (Medicago sativa, Xinjiang-Daye). Under drought treatment, a total of 4446 genes, 859 proteins, and 524 metabolites showed significant differences in abundance. Integrative analysis of the multi-omics data revealed that regulatory modules involved in flavonoid biosynthesis, plant hormone signalling transduction, linoleic acid metabolism, and amino acid biosynthesis play crucial roles in alfalfa adaptation to drought stress. The severity of drought led to the substantial accumulation of flavonoids, plant hormones, free fatty acids, amino acids, and their derivatives in the leaves. Genes such as PAL, 4CL, CHI, CHS, PP2C, ARF_3, and AHP_4 play pivotal regulatory roles in flavonoid biosynthesis and hormone signalling pathways. Differential expression of the LOX gene emerged as a key factor in the elevated levels of free fatty acids. Upregulation of P5CS_1 and GOT1/2 contributed significantly to the accumulation of Pro and Phe contents. ERF19 emerged as a principal positive regulator governing the synthesis of the aforementioned compounds. Furthermore, observations suggest that Xinjiang-Daye alfalfa may exhibit widespread post-transcriptional regulatory mechanisms in adapting to drought stress. The study findings unveil the critical mechanisms by which Xinjiang-Daye alfalfa adapts to drought stress, offering novel insights for the improvement of alfalfa germplasm resources.
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Adaptación Fisiológica , Sequías , Regulación de la Expresión Génica de las Plantas , Medicago sativa , Tetraploidía , Medicago sativa/genética , Medicago sativa/fisiología , Medicago sativa/metabolismo , Adaptación Fisiológica/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Estrés Fisiológico/genética , Flavonoides/metabolismo , Flavonoides/biosíntesis , Reguladores del Crecimiento de las Plantas/metabolismo , MultiómicaRESUMEN
This study investigated the influence of different temperatures (35â High temperature and average indoor ambient temperature of 25â) and lactic acid bacterial additives (Lactiplantibacillus plantarym, Lentilactobacillus buchneri, or a combination of Lactiplantibacillus plantarym and Lentilactobacillus buchneri) on the chemical composition, fermentation quality, and microbial community of alfalfa silage feed. After a 60-day ensiling period, a significant interaction between temperature and additives was observed, affecting the dry matter (DM), crude protein (CP), acid detergent fiber (ADF), and neutral detergent fiber (NDF) of the silage feed (p < 0.05). Temperature had a highly significant impact on the pH value of the silage feed (p < 0.0001). However, the effect of temperature on lactic acid, acetic acid, propionic acid, and butyric acid was not significant (p > 0.05), while the inoculation of additives had a significant effect on lactic acid, acetic acid, and butyric acid (p > 0.05). As for the dynamic changes of microbial community after silage, the addition of three kinds of bacteria increased the abundance of lactobacillus. Among all treatment groups, the treatment group using complex bacteria had the best fermentation effect, indicating that the effect of complex lactic acid bacteria was better than that of single bacteria in high temperature fermentation. In summary, this study explained the effects of different temperatures and lactic acid bacterial additives on alfalfa fermentation quality and microbial community, and improved our understanding of the mechanism of alfalfa related silage at high temperatures.
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Medicago sativa , Ensilaje , Temperatura , Medicago sativa/microbiología , Ensilaje/microbiología , Fermentación , Microbiota , Lactobacillales , Ácido Láctico/metabolismoRESUMEN
Protein grass hay (PGH) was used as a new feed source for lambs to study its effect on fattening performance and meat quality. Fifty-six male lambs were allotted to four experimental groups and fed for eight weeks either alfalfa hay (AH)-based diet (control) or diets in which AH was replaced with 33 %, 66 %, or 99 % PGH. The inclusion of PGH did not affect final body weight, dry matter intake, average daily gain, feed conversion ratio, or carcass weight. Moreover, substituting AH with PGH at any level did not influence the ruminal fermentation or serum biochemical parameters, meat color, water holding capacity, shear force, or amino acid profile. However, relative liver weight was increased with 66 % substitutions. Furthermore, replacing 99 % AH with PGH decreased the meat's pH at 24 h. Higher levels of C18:3n-3, C20:5n-3, and total n-3 PUFA and a lower ratio of n-6: n-3 PUFA were also observed in meat from lambs fed PGH at 99 %. These findings suggest that PGH could be incorporated into the lamb's diet up to 99 % without compromising fattening performance and body health while improving their meat n-3 PUFA deposition.
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Alimentación Animal , Dieta , Poaceae , Carne Roja , Oveja Doméstica , Animales , Masculino , Alimentación Animal/análisis , Dieta/veterinaria , Carne Roja/análisis , Proteínas en la Dieta/análisis , Fenómenos Fisiológicos Nutricionales de los Animales , Rumen/metabolismo , Medicago sativa , Concentración de Iones de Hidrógeno , Ácidos Grasos Omega-3/análisis , Hígado/metabolismo , Hígado/química , Aminoácidos/análisis , Fermentación , Color , Músculo Esquelético/químicaRESUMEN
BACKGROUND: Alfalfa (Medicago sativa L.) is an essential leguminous forage with high nutrition and strong adaptability. The TIFY family is a plant-specific transcription factor identified in many plants. However, few reports have been reported on the phylogenetic analysis and gene expression profiling of TIFY family genes in alfalfa. RESULT: A total of 84 TIFY genes belonging to 4 categories were identified in alfalfa, including 58 MsJAZs, 18 MsZMLs, 4 MsTIFYs and 4 MsPPDs, respectively. qRT-PCR data from 8 genes in different tissues revealed that most MsTIFY genes were highly expressed in roots. The expression of MsTIFY14 was up-regulated after different times in both thrips-resistant and susceptible alfalfa after thrips feeding, and the expression of the remaining MsTIFYs had a strong correlation with the time of thrips feeding. Different abiotic stresses, including drought, salt, and cold, could induce or inhibit the expression of MsTIFY genes to varying degrees. In addition, the eight genes were all significantly up-regulated by JA and/or SA. Interestingly, MsTIFY77 was induced considerably by all the biotic, abiotic, or plant hormones (JA or SA) except ABA. CONCLUSION: Our study identified members of the TIFY gene family in alfalfa and analyzed their structures and possible functions. It laid the foundation for further research on the molecular functions of TIFYs in alfalfa.
Asunto(s)
Regulación de la Expresión Génica de las Plantas , Medicago sativa , Proteínas de Plantas , Factores de Transcripción , Animales , Perfilación de la Expresión Génica , Genes de Plantas , Genoma de Planta , Medicago sativa/genética , Filogenia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Estrés Fisiológico/genética , Factores de Transcripción/genética , Factores de Transcripción/metabolismoRESUMEN
In view of the lack of accurate models for discrete element simulation in the current research and development process of forage harvesting and crushing machinery, the contact parameters were calibrated based on Hertz-Mindlin (no slip) contact model by EDEM simulation software with alfalfa stalk at primary florescence as the research object. Based on the angle of repose, the restitution coefficient, static friction coefficient, rolling friction coefficient of alfalfa stalks were determined through the Placket-Burman test, steepest ascent test and Box-Behnken test. The simulation test of the repose angle was carried out with the determined contact parameters. The results showed that the relative error between the simulated repose angle and the physical test repose angle was 0.48%, which indicated that the calibrated contact parameters could truly reflect the physical characteristics of alfalfa stalks at the primary florescence. It provided a reliable model and parameter calibration method for the discrete element simulation in the research and development process of forage machinery, and also provided a reference for the research and optimization design of forage harvesting, crushing and processing machinery.
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Medicago sativa , Calibración , Fricción , Simulación por ComputadorRESUMEN
Extensive bodies of research are dedicated to the study of seed aging with a particular focus on the roles of reactive oxygen species (ROS), and the ensuing oxidative damage during storage, as a primary cause of seed vigor decreasing. ROS diffuse to the nucleus and damage the telomeres, resulting in a loss of genetic integrity. Protection of telomeres 1 (POT1) is a telomeric protein that binds to the telomere region, and plays an essential role in maintaining genomic stability in plants. In this study, there were totally four MsPOT1 genes obtained from alfalfa genome. Expression analysis of four MsPOT1 genes in germinated seed presented the different expressions. Four MsPOT1 genes displayed high expression levels at the early stage of seed germination, Among the four POT1 genes, it was found that MS. gene040108 was significantly up-regulated in the early germination stage of CK seeds, but down-regulated in aged seeds. RT-qPCR assays and RNA-seq data revealed that MsPOT1-X gene was significantly induced by seed aging treatment. Transgenic seeds overexpressing MsPOT1-X gene in Arabidopsis thaliana and Medicago trunctula exhibited enhanced seed vigor, telomere length, telomerase activity associated with reduced H2O2 content. These results would provide a new way to understand aging stress-responsive MsPOT1 genes for genetic improvement of seed vigor. Although a key gene regulating seed vigor was identified in this study, the specific mechanism of MsPOT1-X gene regulating seed vigor needs to be further explored.
Asunto(s)
Regulación de la Expresión Génica de las Plantas , Medicago sativa , Proteínas de Plantas , Semillas , Medicago sativa/genética , Medicago sativa/metabolismo , Semillas/genética , Semillas/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Telómero/metabolismo , Telómero/genética , Germinación/genética , Plantas Modificadas Genéticamente , Proteínas de Unión a Telómeros/metabolismo , Proteínas de Unión a Telómeros/genética , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Arabidopsis/crecimiento & desarrollo , Especies Reactivas de Oxígeno/metabolismoRESUMEN
Leaves are a key forage part for livestock, and the aging of leaves affects forage biomass and quality. Preventing or delaying premature leaf senescence leads to an increase in pasture biomass accumulation and an improvement in alfalfa quality. NAC transcription factors have been reported to affect plant growth and abiotic stress responses. In this study, 48 NAC genes potentially associated with leaf senescence were identified in alfalfa under dark or salt stress conditions. A phylogenetic analysis divided MsNACs into six subgroups based on similar gene structure and conserved motif. These MsNACs were unevenly distributed in 26 alfalfa chromosomes. The results of the collinearity analysis show that all of the MsNACs were involved in gene duplication. Some cis-acting elements related to hormones and stress were screened in the 2-kb promoter regions of MsNACs. Nine of the MsNAC genes were subjected to qRT-PCR to quantify their expression and Agrobacterium-mediated transient expression to verify their functions. The results indicate that Ms.gene031485, Ms.gene032313, Ms.gene08494, and Ms.gene77666 might be key NAC genes involved in alfalfa leaf senescence. Our findings extend the understanding of the regulatory function of MsNACs in leaf senescence.
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Regulación de la Expresión Génica de las Plantas , Medicago sativa , Filogenia , Hojas de la Planta , Proteínas de Plantas , Factores de Transcripción , Medicago sativa/genética , Medicago sativa/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Hojas de la Planta/genética , Hojas de la Planta/metabolismo , Hojas de la Planta/crecimiento & desarrollo , Transcriptoma , Familia de Multigenes , Senescencia de la Planta/genética , Estrés Salino/genética , Perfilación de la Expresión Génica , OscuridadRESUMEN
BACKGROUND: Drought stress restricts the growth, distribution and productivity of alfalfa (Medicago sativa L.). In order to study the response differences of alfalfa cultivars to drought stress, we previously carried out physiological and molecular comparative analysis on two alfalfa varieties with contrasting drought resistance (relatively drought-tolerant Longdong and drought-sensitive Algonquin). However, the differences in proteomic factors of the two varieties in response to drought stress still need to be further studied. Therefore, TMT-based quantitative proteomic analysis was performed using leaf tissues of the two alfalfa cultivars to identify and uncover differentially abundant proteins (DAPs). RESULTS: In total, 677 DAPs were identified in Algonquin and 277 in Longdong under drought stress. Subsequently, we conducted various bioinformatics analysis on these DAPs, including subcellular location, functional classification and biological pathway enrichment. The first two main COG functional categories of DAPs in both alfalfa varieties after drought stress were 'Translation, ribosomal structure and biogenesis' and 'Posttranslational modification, protein turnover, chaperones'. According to KEGG database, the DAPs of the two alfalfa cultivars after drought treatment were differentially enriched in different biological pathways. The DAPs from Algonquin were enriched in 'photosynthesis' and 'ribosome'. The pathways of 'linoleic acid metabolism', 'protein processing in endoplasmic reticulum' and 'RNA transport' in Longdong were significantly enriched. Finally, we found significant differences in DAP enrichment and expression patterns between Longdong and Algonquin in glycolysis/glycogenesis, TCA cycle, photosynthesis, protein biosynthesis, flavonoid and isoflavonoid biosynthesis, and plant-pathogen interaction pathway after drought treatment. CONCLUSIONS: The differences of DAPs involved in various metabolic pathways may explain the differences in the resistance of the two varieties to drought stress. These DAPs can be used as candidate proteins for molecular breeding of alfalfa to cultivate new germplasm with more drought tolerance to adapt to unfavorable environments.
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Sequías , Medicago sativa , Proteínas de Plantas , Proteómica , Estrés Fisiológico , Medicago sativa/genética , Medicago sativa/metabolismo , Medicago sativa/fisiología , Proteómica/métodos , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Espectrometría de Masas en Tándem , Proteoma/metabolismo , Biología Computacional/métodos , Regulación de la Expresión Génica de las Plantas , Hojas de la Planta/metabolismoRESUMEN
Alfalfa (Medicago L.) is a high-quality perennial leguminous forage with the advantages of salt tolerance, mowing tolerance, high protein content, and other economically valuable characteristics. As the sixth class of plant hormones, brassinosteroids (BRs) play indispensable roles in modulating a variety of plant growth, maturation, and environmental adaptation processes, thereby influencing vegetal expansion and development. Brassinosteroid signal kinases (BSKs) are key cytoplasmic receptor kinases downstream of the BR signaling transduction pathway, participating in plant growth, development, and stress regulation. However, the phylogenetic and expression pattern analyses of the BSK gene family among the five alfalfa species have rarely been reported; in this study, 52 BSK family members were found in the genomes of the five subspecies, and phylogenetic trees were constructed according to protein sequences, allowing us to categorize all BSKs into seven distinct groups. Domain, conserved motif, and exon-intron structural analyses showed that most BSK members were relatively conserved, except for MtBSK3-2, MtBSK7-1, and MtBSK7-2, which may be truncated members. Intra-species collinearity and Ka/Ks analyses showed that purifying selection influenced BSK genes during evolution; most of the cis-acting elements in the promoter region were associated with responses, such as light, defense, and stress, anaerobic induction, MeJA, and abscisic acid. Expression pattern analysis indicated that the majority of alfalfa genes exhibited downregulation after reaching a peak at 0.5 h after treatment with 250 mM NaCl, especially for MsBSK14, MsBSK15, MsBSK17, MsBSK19, and MsBSK21; meanwhile, MsBSK4, MsBSK7, and MsBSK9 increased and were highly expressed at 12 h, demonstrating significantly altered expression patterns under salt stress; furthermore, MsBSK4, MsBSK7, and MsBSK9 exhibited expression specifically in the leaves. qRT-PCR analysis confirmed the expression trends for MsBSK4, MsBSK7, MsBSK9, MsBSK14, MsBSK15, and MsBSK16 matched the transcriptome data. However, the trends for MsBSK17, MsBSK19, and MsBSK21 diverged from the transcriptome data. Our study may provide a foundation for further functional analyses of BSK genes in growth, development, and salt stress tolerance in alfalfa.
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Brasinoesteroides , Regulación de la Expresión Génica de las Plantas , Familia de Multigenes , Filogenia , Proteínas de Plantas , Estrés Salino , Brasinoesteroides/metabolismo , Estrés Salino/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Genoma de Planta , Transducción de Señal/genética , Perfilación de la Expresión Génica , Proteínas Quinasas/genética , Proteínas Quinasas/metabolismo , Medicago sativa/genéticaRESUMEN
BACKGROUND: Researchers have investigated different techniques for synthesis of carbon dots. These techniques include Arc discharge, laser ablation, oxidation, water/solvothermal, and chemical vapor deposition. However, these techniques suffer from some limitations like the utilization of gaseous charged particles, high current, high temperature, potent oxidizing agents, non-environmentally friendly carbon sources, and the generation of uneven particle size. Therefore, there was a significant demand for the adoption of a new technology that combines the environmentally friendly aspects of both bio-based carbon sourcing and synthesis technique. RESULTS: Medicago sativa L (alfalfa)-derived N, S-CDs have been successfully synthesized via microwave irradiation. The N,S-CDs exhibit strong fluorescence (λex/em of 320/420 nm) with fluorescence quantum yield of 2.2 % and high-water solubility. The produced N,S-CDs were characterized using TEM, EDX, Zeta potential analysis, IR, UV-Visible, and fluorescence spectroscopy. The average diameter of the produced N, S-CDs was 4.01 ± 1.2 nm, and the Zeta potential was -24.5 ± 6.63 mv. The stability of the produced nano sensors was also confirmed over wide pH range, long time, and in presence of different ions. The synthesized N, S-CDs were employed to quantify the antibacterial drug, nifuroxazide (NFZ), by fluorescence quenching via inner filter effect mechanism. The method was linear with NFZ concentration ranging from 1.0 to 30.0 µM. LOD and LOQ were 0.16 and 0.49 µM, respectively. The method was applied to quantify NFZ in simulated gastric juice (SGJ) with % recovery 99.59 ± 1.4 in addition to pharmaceutical dosage forms with % recovery 98.75 ± 0.61 for Antinal Capsules® and 100.63 ± 1.54 for Antinal suspension®. The Method validation was performed in compliance with the criteria outlined by ICH. SIGNIFICANCE AND NOVELTY: The suggested approach primarily centers on the first-time use of alfalfa, an ecologically sustainable source of dopped-CDs, and a cost-effective synthesis technique via microwave irradiation, which is characterized by low energy consumption, minimized reaction time, and the ability to control the size of the produced CDs. This is in line with the growing global recognition of the implementation of green analytical chemistry principles.
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Biomasa , Jugo Gástrico , Medicago sativa , Microondas , Nitrofuranos , Medicago sativa/química , Nitrofuranos/análisis , Jugo Gástrico/química , Tecnología Química Verde , Hidroxibenzoatos/análisis , Hidroxibenzoatos/química , Puntos Cuánticos/química , Humanos , Tamaño de la PartículaRESUMEN
BACKGROUND: Alfalfa (Medicago sativa L.) is the most widely planted legume forage and one of the most economically valuable crops in the world. Serine hydroxymethyltransferase (SHMT), a pyridoxal phosphate-dependent enzyme, plays crucial roles in plant growth, development, and stress responses. To date, there has been no comprehensive bioinformatics investigation conducted on the SHMT genes in M. sativa. RESULTS: Here, we systematically analyzed the phylogenetic relationship, expansion pattern, gene structure, cis-acting elements, and expression profile of the MsSHMT family genes. The result showed that a total of 15 SHMT members were identified from the M. sativa genome database. Phylogenetic analysis demonstrated that the MsSHMTs can be divided into 4 subgroups and conserved with other plant homologues. Gene structure analysis found that the exons of MsSHMTs ranges from 3 to 15. Analysis of cis-acting elements found that each of the MsSHMT genes contained different kinds of hormones and stress-related cis-acting elements in their promoter regions. Expression and function analysis revealed that MsSHMTs expressed in all plant tissues. qRT-PCR analysis showed that MsSHMTs induced by ABA, Salt, and drought stresses. CONCLUSIONS: These results provided definite evidence that MsSHMTs might involve in growth, development and adversity responses in M. sativa, which laid a foundation for future functional studies of MsSHMTs.
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Regulación de la Expresión Génica de las Plantas , Glicina Hidroximetiltransferasa , Medicago sativa , Familia de Multigenes , Filogenia , Estrés Fisiológico , Medicago sativa/genética , Estrés Fisiológico/genética , Glicina Hidroximetiltransferasa/genética , Glicina Hidroximetiltransferasa/metabolismo , Genoma de Planta , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Perfilación de la Expresión Génica , Sequías , Regiones Promotoras GenéticasRESUMEN
Numerous studies have investigated seed aging, with a particular emphasis on the involvement of reactive oxygen species. Reactive oxygen species diffuse into the nucleus and damage telomeres, resulting in loss of genetic integrity. Telomerase reverse transcriptase (TERT) plays an essential role in maintaining plant genomic stability. Genome-wide analyses of TERT genes in alfalfa (Medicago sativa) have not yet been conducted, leaving a gap in our understanding of the mechanisms underlying seed aging associated with TERT genes. In this study, four MsTERT genes were identified in the alfalfa genome. The expression profiles of the four MsTERT genes during seed germination indicated that MS. gene79077 was significantly upregulated by seed aging. Transgenic seeds overexpressing MS. gene79077 in Arabidopsis exhibited enhanced tolerance to seed aging by reducing the levels of H2O2 and increasing telomere length and telomerase activity. Furthermore, transcript profiling of aging-treated Arabidopsis wild-type and overexpressing seeds showed an aging response in genes related to glutathione-dependent detoxification and antioxidant defense pathways. These results revealed that MS. gene79077 conferred Arabidopsis seed-aging tolerance via modulation of antioxidant defense and telomere homeostasis. This study provides a new way to understand stress-responsive MsTERT genes for the potential genetic improvement of seed vigor.
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Arabidopsis , Regulación de la Expresión Génica de las Plantas , Medicago sativa , Semillas , Telomerasa , Homeostasis del Telómero , Telómero , Arabidopsis/genética , Medicago sativa/genética , Telomerasa/genética , Telomerasa/metabolismo , Semillas/genética , Telómero/genética , Telómero/metabolismo , Plantas Modificadas Genéticamente , Germinación/genética , Peróxido de Hidrógeno/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Antioxidantes/metabolismo , Senescencia de la Planta/genéticaRESUMEN
Endophytic bacteria can promote plant growth and accelerate pollutant degradation. However, it is unclear whether endophytic consortia (Consortium_E) can stabilize colonisation and degradation. We inoculated Consortium_E into the rhizosphere to enhance endophytic bacteria survival and promote pollutant degradation. Rhizosphere-inoculated Consortium_E enhanced polycyclic aromatic hydrocarbon (PAH) degradation rates by 11.5-13.1 % compared with sole bioaugmentation and plant treatments. Stable-isotope-probing (SIP) showed that the rhizosphere-inoculated Consortium_E had the largest number of degraders (8 amplicon sequence variants). Furthermore, only microbes from Consortium_E were identified among the degraders in bioaugmentation treatments, indicating that directly participated in phenanthrene metabolism. Interestingly, Consortium_E reshaped the community structure of degraders without significantly altering the rhizosphere community structure, and strengthened the core position of degraders in the network, facilitating close interactions between degraders and non-degraders in the rhizosphere, which were crucial for ensuring stable functionality. The synergistic effect between plants and Consortium_E significantly enhanced the upregulation of aromatic hydrocarbon degradation and auxiliary degradation pathways in the rhizosphere. These pathways showed a non-significant increasing trend in the uninoculated rhizosphere compared with the control, indicating that Consortium_E primarily promotes rhizosphere effects. Our results explore the Consortium_E bioaugmentation mechanism, providing a theoretical basis for the ecological restoration of contaminated soils.
Asunto(s)
Biodegradación Ambiental , Medicago sativa , Hidrocarburos Policíclicos Aromáticos , Rizosfera , Contaminantes del Suelo , Hidrocarburos Policíclicos Aromáticos/metabolismo , Contaminantes del Suelo/metabolismo , Medicago sativa/microbiología , Medicago sativa/metabolismo , Microbiota , Endófitos/metabolismo , Microbiología del Suelo , Bacterias/metabolismo , Bacterias/genéticaRESUMEN
Soil salinity constrains growth, development and yield of alfalfa (Medicago sativa L.). To illustrate the molecular mechanisms responsible for salt tolerance, a comparative proteome analysis was explored to characterize protein profiles of alfalfa seedling roots exposed to 100 and 200 mM NaCl for three weeks. There were 52 differentially expressed proteins identified, among which the mRNA expressions of 12 were verified by Real-Time-PCR analysis. The results showed increase in abundance of ascorbate peroxidase, POD, CBS protein and PR-10 in salt-stressed alfalfa, suggesting an effectively antioxidant and defense systems. Alfalfa enhanced protein quality control system to refold or degrade abnormal proteins induced by salt stress through upregulation of unfolded protein response (UPR) marker PDIs and molecular chaperones (eg. HSP70, TCP-1, and GroES) as well as the ubiquitin-proteasome system (UPS) including ubiquitin ligase enzyme (E3) and proteasome subunits. Upregulation of proteins responsible for calcium signal transduction including calmodulin and annexin helped alfalfa adapt to salt stress. Specifically, annexin (MsANN2), a key Ca2+-binding protein, was selected for further characterization. The heterologous of the MsANN2 in Arabidopsis conferred salt tolerance. These results provide detailed information for salt-responsive root proteins and highlight the importance of MsANN2 in adapting to salt stress in alfalfa.
Asunto(s)
Anexinas , Medicago sativa , Proteínas de Plantas , Raíces de Plantas , Proteómica , Tolerancia a la Sal , Medicago sativa/genética , Medicago sativa/efectos de los fármacos , Medicago sativa/metabolismo , Raíces de Plantas/metabolismo , Raíces de Plantas/efectos de los fármacos , Raíces de Plantas/genética , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Tolerancia a la Sal/genética , Proteómica/métodos , Anexinas/metabolismo , Anexinas/genética , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , Plantas Modificadas Genéticamente , Estrés Salino , Arabidopsis/genética , Arabidopsis/metabolismo , Arabidopsis/efectos de los fármacos , Proteoma/metabolismoRESUMEN
Saline-alkali stress is one of the main abiotic stresses that limits plant growth. Salt stress has been widely studied, but alkaline salt degradation caused by NaHCO3 has rarely been investigated. In the present study, the alfalfa cultivar 'Zhongmu No. 1' was treated with 50 mM NaHCO3 (0, 4, 8, 12 and 24 h) to study the resulting enzyme activity and changes in mRNA, miRNA and metabolites in the roots. The results showed that the enzyme activity changed significantly after alkali stress treatment. The genomic analysis revealed 14,970 differentially expressed mRNAs (DEMs), 53 differentially expressed miRNAs (DEMis), and 463 differentially accumulated metabolites (DAMs). Combined analysis of DEMs and DEMis revealed that 21 DEMis negatively regulated 42 DEMs. In addition, when combined with Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis of DEMs and DAMs, we found that phenylpropanoid biosynthesis, flavonoid biosynthesis, starch and sucrose metabolism and plant hormone signal transduction played important roles in the alkali stress response. The results of this study further elucidated the regulatory mechanism underlying the plant response to alkali stress and provided valuable information for the breeding of new saline-alkaline tolerance plant varieties.
Asunto(s)
Regulación de la Expresión Génica de las Plantas , Medicago sativa , MicroARNs , Estrés Fisiológico , Medicago sativa/genética , Medicago sativa/metabolismo , Medicago sativa/efectos de los fármacos , Estrés Fisiológico/genética , MicroARNs/genética , MicroARNs/metabolismo , Álcalis , Raíces de Plantas/metabolismo , Raíces de Plantas/genética , ARN Mensajero/genética , ARN Mensajero/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , MultiómicaRESUMEN
Cadmium (Cd) toxicity poses a significant threat to soil health and sustainable food production. Its bioaccumulation in plant tissues induces phytotoxicity by affecting physiological and biochemical attributes, leading to a reduction in plant biomass and production. Recently, nanotechnology has emerged as a promising approach for addressing heavy metal toxicity in an eco-friendly manner to enhance crop production. However, the comparative role of foliar applied calcium oxide nanoparticles (CaO-NPs) and bulk calcium fertilizer under Cd stress in alfalfa remains unexplored. Herein, we studied the ameliorative role of CaO-NPs and bulk calcium (50 and 100 mg L-1) to alleviate Cd stress (30 mg kg-1) in alfalfa seedlings. Plants exposed to Cd exhibited significant decreases in morpho-physiological traits, gas exchange attributes, and pigment contents as well as increase in Cd bioaccumulation in plant tissues. Notably, exogenous application of CaO-NPs ameliorates the toxic impact of Cd by enhancing plant biomass (45%), fluorescence efficiency and gaseous exchange attributes. The maximum dose of CaO-NPs induced Cd-tolerance response accompanied by a significant increase in antioxidative enzyme activities, such as superoxide dismutase (SOD; 29%), peroxidase (POD; 41%), catalase (CAT; 36%) and ascorbate peroxidase (APX; 49%), which play positive roles in ROS scavenging. TEM examination further revealed the protective role of these NPs in averting Cd-induced damage to leaf ultrastructure and mesophyll cells. Furthermore, CaO-NPs had a substantial influence on both Cd and Ca2+ accumulation in plant tissues, while qRTâPCR analysis demonstrated higher expression of antioxidant defense genes viz. Cu/ZnSOD (0.38 fold change (FC)), MtPOD (0.51 FC), MtCAT (0.61 FC) and MtAPX (0.79 FC) under CaO-NPs application, over Cd control. Overall, our findings suggested that exogenous CaO-NPs could be effective in alleviating the adverse effects of Cd on alfalfa seedlings to ensure food safety and support sustainable agriculture.
Asunto(s)
Antioxidantes , Cadmio , Compuestos de Calcio , Fertilizantes , Medicago sativa , Nanopartículas , Estrés Oxidativo , Óxidos , Fotosíntesis , Medicago sativa/efectos de los fármacos , Medicago sativa/metabolismo , Medicago sativa/genética , Cadmio/toxicidad , Compuestos de Calcio/farmacología , Óxidos/farmacología , Estrés Oxidativo/efectos de los fármacos , Fotosíntesis/efectos de los fármacos , Antioxidantes/metabolismo , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , Calcio/metabolismoRESUMEN
Alfalfa often suffers from low temperature during spring rejuvenation, so it is important to improve the cold tolerance of alfalfa leaves for its smooth rejuvenation, and the alternative pathway (AP) could effectively improve the plant's tolerance. In this study, the contribution of AP on spring rejuvenation of alfalfa was investigated in Xinmu No.4 and Gannong No.5 with different fall dormancy levels. Though the protein and AP capacity were decreased during the rejuvenation, the ratio of AP/TP were increased in two alfalfa varieties, compared to those in alfalfa before overwintering. This indicated that AP had positive response to alfalfa rejuvenation. The limitation of AP significantly affected the leaf length, leaf width and growth rate of greening alfalfa, showing that AP played an important role in alfalfa rejuvenation. Inhibition of AP resulted in a significant decrease in Pn, Ci, Gs and stomatal structure deformity, suggestion that AP affected photosynthesis by influencing stomatal development during rejuvenation. AP reduces oxidative damage to PSII core protein repair in alfalfa leaves and optimizes photosynthesis by up-regulating NADP-MDH activity, decreasing the accumulation of excess reducing power in the chloroplasts, and by increasing SOD and POD activities and decreasing the accumulation of hydrogen peroxide. The higher proportion of AP keeps it more tolerant to low temperature for rejuvenation in Xinmu No.4 with a lower fall dormancy level.