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1.
Int J Mol Sci ; 22(17)2021 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-34502209

RESUMO

The contamination of maize by Fusarium species able to produce mycotoxins raises great concern worldwide since they can accumulate these toxic metabolites in field crop products. Furthermore, little information exists today on the ability of Fusarium proliferatum and Fusarium graminearum, two well know mycotoxigenic species, to translocate from the seeds to the plants up to the kernels. Marketing seeds coated with fungicide molecules is a common practice; however, since there is a growing need for reducing chemicals in agriculture, new eco-friendly strategies are increasingly tested. Technologies based on ionized gases, known as plasmas, have been used for decades, with newer material surfaces, products, and approaches developed continuously. In this research, we tested a plasma-generated bilayer coating for encapsulating prothioconazole at the surface of maize seeds, to protect them from F. graminearum and F. proliferatum infection. A minimum amount of chemical was used, in direct contact with the seeds, with no dispersion in the soil. The ability of F. graminearum and F. proliferatum species to translocate from seeds to seedlings of maize has been clearly proven in our in vitro experiments. As for the use of plasma technology, the combined use of the plasma-generated coating with embedded prothioconazole was the most efficient approach, with a higher reduction of the infection of the maize seminal root system and stems. The debated capability of the two Fusarium species to translocate from seeds to seedlings has been demonstrated. The plasma-generated coating with embedded prothioconazole resulted in a promising sustainable approach for the protection of maize seedlings.


Assuntos
Contaminação de Alimentos/análise , Fungicidas Industriais/farmacologia , Fusarium/crescimento & desenvolvimento , Gases em Plasma/farmacologia , Plântula/crescimento & desenvolvimento , Triazóis/farmacologia , Zea mays/crescimento & desenvolvimento , Contaminação de Alimentos/prevenção & controle , Fusarium/efeitos dos fármacos , Plântula/efeitos dos fármacos , Plântula/microbiologia , Zea mays/efeitos dos fármacos , Zea mays/microbiologia
2.
Int J Mol Sci ; 22(17)2021 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-34502218

RESUMO

Phosphorus (P) deficiency is an important challenge the world faces while having to increase crop yields. It is therefore necessary to select maize (Zea may L.) genotypes with high phosphorus use efficiency (PUE). Here, we extensively analyzed the biomass, grain yield, and PUE-related traits of 359 maize inbred lines grown under both low-P and normal-P conditions. A significant decrease in grain yield per plant and biomass, an increase in PUE under low-P condition, as well as significant correlations between the two treatments were observed. In a genome-wide association study, 49, 53, and 48 candidate genes were identified for eleven traits under low-P, normal-P conditions, and in low-P tolerance index (phenotype under low-P divided by phenotype under normal-P condition) datasets, respectively. Several gene ontology pathways were enriched for the genes identified under low-P condition. In addition, seven key genes related to phosphate transporter or stress response were molecularly characterized. Further analyses uncovered the favorable haplotype for several core genes, which is less prevalent in modern lines but often enriched in a specific subpopulation. Collectively, our research provides progress in the genetic dissection and molecular characterization of PUE in maize.


Assuntos
Regulação da Expressão Gênica de Plantas , Fósforo/metabolismo , Proteínas de Plantas/metabolismo , Polimorfismo de Nucleotídeo Único , Locos de Características Quantitativas , Estresse Fisiológico , Zea mays/genética , Mapeamento Cromossômico , Cromossomos de Plantas , Estudo de Associação Genômica Ampla , Fenótipo , Proteínas de Plantas/genética , Zea mays/crescimento & desenvolvimento , Zea mays/metabolismo
3.
BMC Plant Biol ; 21(1): 434, 2021 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-34556041

RESUMO

BACKGROUND: Kernel development and starch formation are the primary determinants of maize yield and quality, which are considerably influenced by drought stress. To clarify the response of maize kernel to drought stress, we established well-watered (WW) and water-stressed (WS) conditions at 1-30 days after pollination (dap) on waxy maize (Zea mays L. sinensis Kulesh). RESULTS: Kernel development, starch accumulation, and activities of starch biosynthetic enzymes were significantly reduced by drought stress. The morphology of starch granules changed, whereas the grain filling rate was accelerated. A comparative proteomics approach was applied to analyze the proteome change in kernels under two treatments at 10 dap and 25 dap. Under the WS conditions, 487 and 465 differentially accumulated proteins (DAPs) were identified at 10 dap and 25 dap, respectively. Drought induced the downregulation of proteins involved in the oxidation-reduction process and oxidoreductase, peroxidase, catalase, glutamine synthetase, abscisic acid stress ripening 1, and lipoxygenase, which might be an important reason for the effect of drought stress on kernel development. Notably, several proteins involved in waxy maize endosperm and starch biosynthesis were upregulated at early-kernel stage under WS conditions, which might have accelerated endosperm development and starch synthesis. Additionally, 17 and 11 common DAPs were sustained in the upregulated and downregulated DAP groups, respectively, at 10 dap and 25 dap. Among these 28 proteins, four maize homologs (i.e., A0A1D6H543, B4FTP0, B6SLJ0, and A0A1D6H5J5) were considered as candidate proteins that affected kernel development and drought stress response by comparing with the rice genome. CONCLUSIONS: The proteomic changes caused by drought were highly correlated with kernel development and starch accumulation, which were closely related to the final yield and quality of waxy maize. Our results provided a foundation for the enhanced understanding of kernel development and starch formation in response to drought stress in waxy maize.


Assuntos
Secas , Grão Comestível/crescimento & desenvolvimento , Grão Comestível/metabolismo , Amido/metabolismo , Ceras/metabolismo , Zea mays/crescimento & desenvolvimento , Zea mays/metabolismo , China , Desidratação/metabolismo , Proteômica , Água/metabolismo
4.
Int J Mol Sci ; 22(16)2021 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-34445334

RESUMO

The aim of the study was to demonstrate the biostimulating effect of exogenous melatonin (MEL) applied to seeds via hydroconditioning. It was indicated that only well-chosen application technique and MEL dose guarantees success concerning seed germination and young seedlings growth under stress conditions. For maize seed, 50 µM of MEL appeared to be the optimal dose. It improved seed germination and embryonic axes growth especially during chilling stress (5 °C/14 days) and during regeneration after its subsided. Unfortunately, MEL overdosing lowered IAA level in dry seeds and could disrupt the ROS-dependent signal transduction pathways. Very effective antioxidant MEL action was confirmed by low level of protein oxidative damage and smaller quantity of lipid oxidation products in embryonic axes isolated from seeds pre-treated with MEL and then exposed to cold. The stimulatory effects of MEL on antioxidant enzymes: SOD, APX and GSH-PX and on GST-a detoxifying enzyme, was also demonstrated. It was indicated for the first time, that MEL induced defence strategies against stress at the cytological level, as appearing endoreplication in embryonic axes cells even in the seeds germinating under optimal conditions (preventive action), but very intensively in those germinating under chilling stress conditions (intervention action), and after stress removal, to improve regeneration.


Assuntos
Resposta ao Choque Frio , Melatonina/farmacologia , Zea mays , Agricultura/métodos , Antioxidantes/metabolismo , Resposta ao Choque Frio/efeitos dos fármacos , Resposta ao Choque Frio/genética , Endorreduplicação/efeitos dos fármacos , Germinação/efeitos dos fármacos , Germinação/genética , Plântula/efeitos dos fármacos , Plântula/genética , Plântula/crescimento & desenvolvimento , Plântula/metabolismo , Sementes/efeitos dos fármacos , Sementes/genética , Sementes/crescimento & desenvolvimento , Sementes/metabolismo , Temperatura , Zea mays/efeitos dos fármacos , Zea mays/genética , Zea mays/crescimento & desenvolvimento , Zea mays/metabolismo
5.
Biomolecules ; 11(7)2021 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-34356629

RESUMO

Soil salinity is the major limiting factor restricting plant growth and development. Little is known about the comparative and combined effects of gibberellic acid (GA3) seed priming and foliar application on maize under salt stress. The current study determined the impact of different application methods of GA3 on morpho-physiological, biochemical and molecular responses of maize seedlings under three salinity stress treatments (no salinity, moderate salinity-6 dS m-1, and severe salinity-12 dS m-1). The GA3 treatments consisted of control, hydro-priming (HP), water foliar spray (WFS), HP + WFS, seed priming with GA3 (GA3P, 100 mg L-1), foliar spray with GA3 (GA3FS, 100ppm) and GA3P + GA3FS. Salt stress particularly at 12 dS m-1 reduced the length of shoots and roots, fresh and dry weights, chlorophyll, and carotenoid contents, K+ ion accumulation and activities of antioxidant enzymes, while enhanced the oxidative damage and accumulation of the Na+ ion in maize plants. Nevertheless, the application of GA3 improved maize growth, reduced oxidative stress, and increased the antioxidant enzymes activities, antioxidant genes expression, and K+ ion concentration under salt stress. Compared with control, the GA3P + GA3FS recorded the highest increase in roots and shoots length (19-37%), roots fresh and dry weights (31-43%), shoots fresh and dry weights (31-47%), chlorophyll content (21-70%), antioxidant enzymes activities (73.03-150.74%), total soluble protein (13.05%), K+ concentration (13-23%) and antioxidants genes expression levels under different salinity levels. This treatment also reduced the H2O2 content, and Na+ ion concentration. These results indicated that GA3P + GA3FS could be used as an effective tool for improving the maize growth and development, and reducing the oxidative stress in salt-contaminated soils.


Assuntos
Antioxidantes/metabolismo , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Giberelinas/farmacologia , Tolerância ao Sal/efeitos dos fármacos , Zea mays , Tolerância ao Sal/genética , Zea mays/genética , Zea mays/crescimento & desenvolvimento
6.
Molecules ; 26(16)2021 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-34443651

RESUMO

Caraway (Carum carvi L.) essential oil is a candidate for botanical herbicides. A hypothesis was formulated that the sand-applied maltodextrin-coated caraway oil (MCEO) does not affect the growth of maize (Zea mays L.). In the pot experiment, pre-emergence application of five doses of MCEO was tested on four maize cultivars up to the three-leaf growth stage. The morphological analyses were supported by the measurements of relative chlorophyll content (SPAD), two parameters of chlorophyll a fluorescence, e.g., Fv/Fm and Fv/F0, and fluorescence emission spectra. The analyzed MCEO contained 6.5% caraway EO with carvone and limonene as the main compounds, constituting 95% of the oil. The MCEO caused 7-day delays in maize emergence from the dose of 0.9 g per pot (equal to 96 g m-2). Maize development at the three-leaf growth stage, i.e., length of roots, length of leaves, and biomass of shoots and leaves, was significantly impaired already at the lowest dose of MCEO: 0.4 g per pot, equal to 44 g m-2. A significant drop of both chlorophyll a fluorescence parameters was noted, on average, from the dose of 0.7 g per pot, equal to 69 g m-2. Among the tested cultivars, cv. Rywal and Pomerania were less susceptible to the MCEO compared to the cv. Kurant and Podole. In summary, maize is susceptible to the pre-emergence, sand-applied MCEO from the dose of 44 g m-2.


Assuntos
Óleos Voláteis/farmacologia , Óleos Vegetais/farmacologia , Zea mays/efeitos dos fármacos , Zea mays/crescimento & desenvolvimento , Biomassa , Carum/química , Clorofila A/metabolismo , Monoterpenos Cicloexânicos/química , Monoterpenos Cicloexânicos/farmacologia , Fluorescência , Herbicidas/farmacologia , Limoneno/química , Limoneno/farmacologia , Fotossíntese/efeitos dos fármacos , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/metabolismo , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Zea mays/metabolismo
7.
Int J Mol Sci ; 22(16)2021 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-34445561

RESUMO

Among numerous contaminants, the ubiquitous occurrence of nonsteroidal anti-inflammatory drugs (NSAIDs) in the environment and their plausible harmful impact on nontarget organisms have made them one of the most important areas of concern in recent years. Crop plants can also potentially be exposed to NSAIDs, since the concentration of these pharmaceuticals is constantly rising in the surface water and soil. Our goal was to evaluate the stress response of two crop plants, maize and tomato, to treatment with selected NSAIDs, naproxen and diclofenac. The focus of the research was on the growth response, photosynthetic efficiency, selected oxidative stress factors (such as the H2O2 level and the rate of lipid peroxidation) as well as the total phenolic content, which represents the non-enzymatic protectants against oxidative stress. The results indicate that susceptibility to the NSAIDs that were tested is dependent on the plant species. A higher sensitivity of tomato manifested in growth inhibition, a decrease in the content of the photosynthetic pigments and a reduction in the maximum quantum efficiency of PSII and the activity of PSII, which was estimated using the Fv/Fm and Fv/F0 ratios. Based on the growth results, it was also possible to reveal that diclofenac had a more toxic effect on tomato. In contrast to tomato, in maize, neither the content of the photosynthetic pigments nor growth appeared to be affected by DFC and NPX. However, both drugs significantly decreased in maize Fv and Fm, which are particularly sensitive to stress. A higher H2O2 concentration accompanied, in most cases, increasing lipid peroxidation, indicating that oxidative stress occurred in response to the selected NSAIDs in the plant species that were studied. The higher phenolic content of the plants after NSAIDs treatment may, in turn, indicate the activation of defense mechanisms in response to the oxidative stress that is triggered by these drugs.


Assuntos
Diclofenaco/farmacologia , Peroxidação de Lipídeos/efeitos dos fármacos , Lycopersicon esculentum/efeitos dos fármacos , Naproxeno/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Zea mays/efeitos dos fármacos , Anti-Inflamatórios não Esteroides/farmacologia , Peróxido de Hidrogênio/farmacologia , Lycopersicon esculentum/crescimento & desenvolvimento , Lycopersicon esculentum/metabolismo , Oxidantes/farmacologia , Fenóis/farmacologia , Zea mays/crescimento & desenvolvimento , Zea mays/metabolismo
8.
Molecules ; 26(15)2021 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-34361755

RESUMO

Zinc (Zn) is an essential micronutrient for plant growth, and Zn deficiency is a global issue, especially in tropical soils. This study aimed to investigate the effects of humic acid (HA) and the Zn addition (Zn sulfate + HA) on the growth of maize and brachiaria in two contrasting Oxisols. The potential complexation of Zn sulfate by HA was evaluated by Fourier-transform infrared (FTIR) spectroscopy analysis. Zinc content and its availability in solution and the shoot and root biomass of maize and brachiaria were determined. FTIR spectroscopy revealed the complexation of Zn sulfate by HA through its S and C functional groups. In both Oxisols, solution Zn increased due to the combined use of Zn and HA. In a soil type-dependent manner, maize biomass and Zn in its shoots were affected only by the exclusive use of Zn fertilization. In the Yellow Oxisol, brachiaria growth and Zn accumulated in its shoot were positively affected by the combined use of Zn fertilization with HA. In the Oxisol with lower organic matter content, HA can assure adequate supplying of residual Zn, while increasing growth of brachiaria cultivated in sequence to maize.


Assuntos
Brachiaria/efeitos dos fármacos , Substâncias Húmicas/análise , Solo/química , Zea mays/efeitos dos fármacos , Sulfato de Zinco/farmacologia , Brachiaria/crescimento & desenvolvimento , Brasil , Fertilizantes/análise , Concentração de Íons de Hidrogênio , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/crescimento & desenvolvimento , Brotos de Planta/efeitos dos fármacos , Brotos de Planta/crescimento & desenvolvimento , Análise de Componente Principal , Espectroscopia de Infravermelho com Transformada de Fourier , Zea mays/crescimento & desenvolvimento , Sulfato de Zinco/análise , Sulfato de Zinco/química
9.
Int J Mol Sci ; 22(16)2021 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-34445215

RESUMO

Zea mays L. is one of the most produced crops, and there are still parts of the world where maize is the basic staple food. To improve agriculture, mankind always looks for new, better methods of growing crops, especially in the current changing climatic conditions. Cold atmospheric pressure plasma (CAPP) has already showed its potential to enhance the culturing of crops, but it still needs more research for safe implementation into agriculture. In this work, it was shown that short CAPP treatment of maize grains had a positive effect on the vitality of grains and young seedlings, which may be connected to stimulation of antioxidant and lytic enzyme activities by short CAPP treatment. However, the prolonged treatment had a negative impact on the germination, growth, and production indexes. CAPP treatment caused the increased expression of genes for heat shock proteins HSP101 and HSP70 in the first two days after sowing. Using comet assay it was observed that shorter treatment times (30-120 s) did not cause DNA damage. Surface diagnostics of plasma-treated grains showed that plasma increases the hydrophilicity of the surface but does not damage the chemical bonds on the surface.


Assuntos
Grão Comestível/crescimento & desenvolvimento , Proteínas de Choque Térmico HSP70/metabolismo , Peptídeo Hidrolases/metabolismo , Proteínas de Plantas/metabolismo , Gases em Plasma/farmacologia , Fatores de Transcrição/metabolismo , Zea mays/crescimento & desenvolvimento , Pressão Atmosférica
10.
BMC Plant Biol ; 21(1): 368, 2021 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-34384391

RESUMO

BACKGROUND: Melatonin is considered a potential plant growth regulator to enhance the growth of plants and increase tolerance to various abiotic stresses. Nevertheless, melatonin's role in mediating stress response in different plant species and growth cycles still needs to be explored. This study was conducted to understand the impact of different melatonin concentrations (0, 50, 100, and 150 µM) applied as a soil drench to maize seedling under drought stress conditions. A decreased irrigation approach based on watering was exposed to maize seedling after drought stress was applied at 40-45% of field capacity. RESULTS: The results showed that drought stress negatively affected the growth behavior of maize seedlings, such as reduced biomass accumulation, decreased photosynthetic pigments, and enhanced the malondialdehyde and reactive oxygen species (ROS). However, melatonin application enhanced plant growth; alleviated ROS-induced oxidative damages by increasing the photosynthetic pigments, antioxidant enzyme activities, relative water content, and osmo-protectants of maize seedlings. CONCLUSIONS: Melatonin treatment also enhanced the stomatal traits, such as stomatal length, width, area, and the number of pores under drought stress conditions. Our data suggested that 100 µM melatonin application as soil drenching could provide a valuable foundation for improving plant tolerance to drought stress conditions.


Assuntos
Melatonina/farmacologia , Reguladores de Crescimento de Plantas/farmacologia , Zea mays/efeitos dos fármacos , Zea mays/crescimento & desenvolvimento , Antioxidantes/metabolismo , Biomassa , Clorofila/metabolismo , Secas , Estresse Oxidativo , Fotossíntese/efeitos dos fármacos , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/ultraestrutura , Proteínas de Plantas/metabolismo , Estômatos de Plantas/efeitos dos fármacos , Estômatos de Plantas/ultraestrutura , Prolina/metabolismo , Espécies Reativas de Oxigênio , Plântula/efeitos dos fármacos , Plântula/crescimento & desenvolvimento , Açúcares/metabolismo , Zea mays/enzimologia , Zea mays/fisiologia
11.
Int J Mol Sci ; 22(15)2021 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-34360681

RESUMO

The function and regulation of lipid metabolic genes are essential for plant male reproduction. However, expression regulation of lipid metabolic genic male sterility (GMS) genes by noncoding RNAs is largely unclear. Here, we systematically predicted the microRNA regulators of 34 maize white brown complex members in ATP-binding cassette transporter G subfamily (WBC/ABCG) genes using transcriptome analysis. Results indicate that the ZmABCG26 transcript was predicted to be targeted by zma-miR164h-5p, and their expression levels were negatively correlated in maize B73 and Oh43 genetic backgrounds based on both transcriptome data and qRT-PCR experiments. CRISPR/Cas9-induced gene mutagenesis was performed on ZmABCG26 and another lipid metabolic gene, ZmFAR1. DNA sequencing, phenotypic, and cytological observations demonstrated that both ZmABCG26 and ZmFAR1 are GMS genes in maize. Notably, ZmABCG26 proteins are localized in the endoplasmic reticulum (ER), chloroplast/plastid, and plasma membrane. Furthermore, ZmFAR1 shows catalytic activities to three CoA substrates in vitro with the activity order of C12:0-CoA > C16:0-CoA > C18:0-CoA, and its four key amino acid sites were critical to its catalytic activities. Lipidomics analysis revealed decreased cutin amounts and increased wax contents in anthers of both zmabcg26 and zmfar1 GMS mutants. A more detailed analysis exhibited differential changes in 54 monomer contents between wild type and mutants, as well as between zmabcg26 and zmfar1. These findings will promote a deeper understanding of miRNA-regulated lipid metabolic genes and the functional diversity of lipid metabolic genes, contributing to lipid biosynthesis in maize anthers. Additionally, cosegregating molecular markers for ZmABCG26 and ZmFAR1 were developed to facilitate the breeding of male sterile lines.


Assuntos
Subfamília G de Transportadores de Cassetes de Ligação de ATP/genética , Aldeído Oxirredutases/genética , Flores/metabolismo , Metabolismo dos Lipídeos , MicroRNAs/metabolismo , Zea mays/metabolismo , Subfamília G de Transportadores de Cassetes de Ligação de ATP/metabolismo , Aldeído Oxirredutases/metabolismo , Flores/genética , Flores/crescimento & desenvolvimento , Regulação da Expressão Gênica de Plantas , Filogenia , Proteínas de Plantas , Pólen/crescimento & desenvolvimento , Pólen/metabolismo , RNA-Seq , Zea mays/genética , Zea mays/crescimento & desenvolvimento
12.
Theor Appl Genet ; 134(10): 3459-3472, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34247253

RESUMO

KEY MESSAGE: Twelve QTL for flowering and leaf number were detected. The ZmWRKY14Hap4 could increase leaf number, flowering time and biomass yield which are promising for silage maize breeding. Silage maize, one of the most important feedstock for ruminants, is widely grown from temperate regions to the tropics. Flowering time and leaf number are two significantly correlated traits and important for the quality, adaptation and biomass yield of silage maize. In this study, a recombinant inbred line population consisting of 215 individuals and an association panel of 369 inbred lines were analysed in field conditions in three locations for 2 consecutive years, and five, four and three quantitative trait loci for the total leaf number, days to anthesis (DTA) and silking (DTS) were detected, which could explain 48.55, 35.37 and 34.22% of total phenotypic variation, respectively. Association analysis of qLN10 on chromosome 10 found that ZmWRKY14 was the candidate gene for leaf number, whose expression level was negatively correlated with the leaf number. There are five haplotypes for ZmWRKY14, and haplotype 4 could significantly increase flowering time, leaf number and biomass yield, but has no obvious influence on ear weight. The optimal allelic combination of ZmWRKY14 and ZCN8 could further increase leaf number and biomass yield. The results will provide important genetic information for silage maize breeding.


Assuntos
Mapeamento Cromossômico/métodos , Flores/crescimento & desenvolvimento , Regulação da Expressão Gênica de Plantas , Folhas de Planta/anatomia & histologia , Proteínas de Plantas/metabolismo , Locos de Características Quantitativas , Zea mays/crescimento & desenvolvimento , Cromossomos de Plantas/genética , Flores/genética , Fenótipo , Melhoramento Vegetal , Folhas de Planta/genética , Folhas de Planta/crescimento & desenvolvimento , Proteínas de Plantas/genética , Zea mays/genética
13.
Int J Mol Sci ; 22(11)2021 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-34199464

RESUMO

The influence of salt stress on gene expression, promoter methylation, and enzymatic activity of the mitochondrial and cytosolic forms of aconitase and fumarase has been investigated in maize (Zea mays L.) seedlings. The incubation of maize seedlings in 150-mM NaCl solution resulted in a several-fold increase of the mitochondrial activities of aconitase and fumarase that peaked at 6 h of NaCl treatment, while the cytosolic activity of aconitase and fumarase decreased. This corresponded to the decrease in promoter methylation of the genes Aco1 and Fum1 encoding the mitochondrial forms of these enzymes and the increase in promoter methylation of the genes Aco2 and Fum2 encoding the cytosolic forms. The pattern of expression of the genes encoding the mitochondrial forms of aconitase and fumarase corresponded to the profile of the increase of the stress marker gene ZmCOI6.1. It is concluded that the mitochondrial and cytosolic forms of aconitase and fumarase are regulated via the epigenetic mechanism of promoter methylation of their genes in the opposite ways in response to salt stress. The role of the mitochondrial isoforms of aconitase and fumarase in the elevation of respiration under salt stress is discussed.


Assuntos
Aconitato Hidratase/genética , Metilação de DNA/genética , Fumarato Hidratase/genética , Estresse Salino/genética , Citosol/enzimologia , Regulação da Expressão Gênica de Plantas/genética , Mitocôndrias/enzimologia , Regiões Promotoras Genéticas/genética , Zea mays/genética , Zea mays/crescimento & desenvolvimento
14.
Methods Mol Biol ; 2287: 323-332, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34270040

RESUMO

Wide hybridization is one of the haploid-inducing techniques that can accelerate the breeding process. Obtaining new cultivars is crucial to solve the problem of the constantly growing world population and global increase in demand for food, feed and renewable energy under changing environmental conditions. Here, we present a detailed protocol for obtaining oat (Avena sativa L.) doubled haploids (DHs) by pollination with maize (Zea mays L.). After fertilization, not only oat homozygotes, but also oat × maize hybrid zygotes can be formed, and during early embryo development, maize chromosomes are preferentially eliminated, which ultimately results in haploid plant formation. This chapter describes a method to produce oat DHs by crossing oat with maize, covering all steps from crossings to haploid plant regeneration and chromosome doubling.


Assuntos
Avena/genética , Hibridização Genética/genética , Zea mays/genética , Avena/crescimento & desenvolvimento , Cromossomos de Plantas/genética , Flores/crescimento & desenvolvimento , Engenharia Genética/métodos , Genótipo , Haploidia , Hibridização de Ácido Nucleico/métodos , Melhoramento Vegetal/métodos , Polinização , Sementes/genética , Zea mays/crescimento & desenvolvimento
15.
Int J Mol Sci ; 22(14)2021 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-34299004

RESUMO

Plant production technologies based solely on the improvement of plants themselves face obstacles resulting from the natural limitations of the biological potential of varieties. Therefore, new substances are sought that positively influence the growth and development of plants and increase resistance to various biotic and abiotic stresses, which also translates into an increase in obtained yields. The exogenous application of various phytoprotectants shows great promise in terms of cost effectiveness compared to traditional breeding methods or transgenic approaches in relation to increasing plant tolerance to abiotic stresses. Quercetin is a strong antioxidant among phenolic compounds, and it plays a physiological and biochemical role in plants. As such, the aim of this research was to assess the effect of an aqueous solution of a quercetin derivative with potassium, applied in various concentrations (0.5%, 1.0%, 3.0% and 5.0%), on the efficiency of the photosynthetic apparatus and biochemical properties of maize. Among the tested variants, compared to the control, the most stimulating effect on the course of physiological processes (PN, gs, ci, CCI, Fv/Fm, Fv/F0, PI) in maize leaves was found in 3.0 and 5.0% aqueous solutions of the quercetin derivative. The highest total antioxidant capacity and total content of polyphenolic compounds were found for plants sprayed with 5.0% quercetin derivative solution; therefore, in this study, the optimal concentration could not be clearly selected.


Assuntos
Antioxidantes/farmacologia , Melhoramento Vegetal/métodos , Potássio/química , Quercetina/farmacologia , Estresse Fisiológico/efeitos dos fármacos , Zea mays/efeitos dos fármacos , Antioxidantes/administração & dosagem , Antioxidantes/química , Clorofila/análise , Clorofila/química , Fluorescência , Fenóis/análise , Folhas de Planta/química , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/fisiologia , Quercetina/administração & dosagem , Quercetina/análogos & derivados , Quercetina/química , Zea mays/crescimento & desenvolvimento , Zea mays/fisiologia
16.
Int J Mol Sci ; 22(13)2021 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-34209973

RESUMO

In maize, the ear shank is a short branch that connects the ear to the stalk. The length of the ear shank mainly affects the transportation of photosynthetic products to the ear, and also influences the dehydration of the grain by adjusting the tightness of the husks. However, the molecular mechanisms of maize shank elongation have rarely been described. It has been reported that the maize ear shank length is a quantitative trait, but its genetic basis is still unclear. In this study, RNA-seq was performed to explore the transcriptional dynamics and determine the key genes involved in maize shank elongation at four different developmental stages. A total of 8145 differentially expressed genes (DEGs) were identified, including 729 transcription factors (TFs). Some important genes which participate in shank elongation were detected via function annotation and temporal expression pattern analyses, including genes related to signal transduction hormones (auxin, brassinosteroids, gibberellin, etc.), xyloglucan and xyloglucan xyloglucosyl transferase, and transcription factor families. The results provide insights into the genetic architecture of maize ear shanks and developing new varieties with ideal ear shank lengths, enabling adjustments for mechanized harvesting in the future.


Assuntos
Perfilação da Expressão Gênica/métodos , Redes Reguladoras de Genes , Zea mays/crescimento & desenvolvimento , Regulação da Expressão Gênica no Desenvolvimento , Regulação da Expressão Gênica de Plantas , Ontologia Genética , Fenótipo , Proteínas de Plantas/genética , Locos de Características Quantitativas , Fatores de Transcrição , Zea mays/genética
17.
Methods Mol Biol ; 2288: 25-48, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34270003

RESUMO

Doubled haploid (DH) technology produces strictly homozygous fertile plant thanks to doubling the chromosomes of a haploid embryo/seedling. Haploid embryos are derived from either male or female germ line cells and hold only half the number of chromosomes found in somatic plant tissues, albeit in a recombinant form due to meiotic genetic shuffling. DH production allows to rapidly fix these recombinant haploid genomes in the form of perfectly homozygous plants (inbred lines), which are produced in two rather than six or more generations. Thus, DH breeding enables fast evaluation of phenotypic traits on homogenous progeny. While for most crops haploid embryos are produced by costly and often genotype-dependent in vitro methods, for maize, two unique in planta systems are available to induce haploid embryos directly in the seed. Two "haploid inducer lines", identified from spontaneous maize mutants, are able to induce embryos of paternal or maternal origin. Although effortless crosses with lines of interest are sufficient to trigger haploid embryos, substantial improvements were necessary to bring DH technology to large scale production. They include the development of modern haploid inducer lines with high induction rates (8-12%), and methods to sort kernels with haploid embryos from the normal ones. Chromosome doubling represents also a crucial step in the DH process. Recent identification of genomic loci involved in spontaneous doubling opens up perspectives for a fully in planta DH pipeline in maize. Although discovered more than 60 years ago, maize haploid inducer lines still make headlines thanks to novel applications and findings. Indeed, maternal haploid induction was elegantly diverted to deliver genome editing machinery in germplasm recalcitrant to transformation techniques. The recent discovery of two molecular players controlling haploid induction allowed to revisit the mechanistic basis of maize maternal haploid induction and to successfully translate haploid induction ability to other crops.


Assuntos
Melhoramento Vegetal/métodos , Zea mays/genética , Cromossomos de Plantas/genética , Produtos Agrícolas/genética , Produtos Agrícolas/crescimento & desenvolvimento , Cruzamentos Genéticos , Diploide , Edição de Genes , Genoma de Planta , Haploidia , Homozigoto , Vigor Híbrido , Modelos Genéticos , Biologia Molecular/métodos , Fenótipo , Sementes/genética , Sementes/crescimento & desenvolvimento , Zea mays/crescimento & desenvolvimento
18.
Methods Mol Biol ; 2287: 105-125, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34270026

RESUMO

Determination of the ploidy level is an essential step when trying to produce doubled haploids (DHs) in any species. Each species and method used to produce DHs has its own frequency of DH production, which means that the rest of plants produced stay haploid. Since haploids are of little use for breeding purposes, it is necessary to distinguish them from true DHs. For this, several methodologies are available, including flow cytometry, chromosome counting, chloroplast counting in stomatal guard cells, measurement of stomatal size and length, counting of nucleoli, evaluation of pollen formation and viability, analysis of cell size, and analysis of morphological markers. However, not all of them are equally easy to use, affordable, reliable, reproducible, and resolutive and therefore useful for a particular case. In this chapter, we revise these methods available to assess the ploidy level of plants, discussing their respective advantages and limitations, and provide some troubleshooting tips and hints to help decide which to choose in each case.


Assuntos
Melhoramento Vegetal/métodos , Zea mays/crescimento & desenvolvimento , Zea mays/genética , Cruzamentos Genéticos , Haploidia , Ploidias , Sementes/genética , Sementes/crescimento & desenvolvimento
19.
Methods Mol Biol ; 2287: 267-279, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34270036

RESUMO

The intergeneric hybridization of wheat (Triticum aestivum L.) with maize (Zea mays L.) enables the production of doubled haploids (DHs) of wheat from all wheat hybrids with high efficiencies. Wheat and maize donor plants are raised in environmentally controlled greenhouses until crossing. Before anthesis, wheat spikes are emasculated and then pollinated with maize. Auxin is applied to each individual wheat floret 1 day after pollination. About 2 weeks after crossing, in vitro embryo culture is performed, enabling the regeneration of haploid wheat plantlets after maize chromosome elimination. Haploid plantlets are transferred to the greenhouse and after recovery, their genome is doubled with colchicine. Haploid plantlets can be sampled for DNA extractions and molecular analyses to aid the rapid discard of undesirable plantlets. Doubled haploid plants are raised in a greenhouse until maturity. Seeds of each fertile DH are harvested and often sown the same year. Several cycles of multiplication and evaluation in replicated plot trials and different geographical locations are then done to select the best candidate(s) for varietal registration.


Assuntos
Hibridização Genética , Melhoramento Vegetal/métodos , Triticum/crescimento & desenvolvimento , Triticum/genética , Zea mays/crescimento & desenvolvimento , Zea mays/genética , Cruzamentos Genéticos , Haploidia , Sementes/genética , Sementes/crescimento & desenvolvimento
20.
Methods Mol Biol ; 2287: 281-293, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34270037

RESUMO

Isolated microspore culture systems have been designed in maize by several groups, mainly from the late 1980s to early 2000s. However, even with optimized protocols, microspore embryogenesis induction has remained very dependent on the genotype in maize, with elite germplasm generally displaying no response or very low response. Yet, these last few years, significant progress has been accomplished in understanding and controlling microspore embryogenesis induction in model dicot and monocot species. This knowledge may be transferred to maize, and isolated microspore culture may gain new interest in this crop, at least for embryogenesis research. The methods we hereby present in detail permit the purification of 3-12 × 105 viable microspores per maize tassel, at the favorable stage for microspore embryogenesis. When cultured in appropriate liquid media, microspores from responsive genotypes give rise to androgenic embryos, which can then be regenerated into fertile doubled haploid plants.


Assuntos
Gametogênese Vegetal , Técnicas de Cultura de Tecidos/métodos , Zea mays/crescimento & desenvolvimento , Meios de Cultura , Haploidia , Pólen/embriologia , Pólen/genética , Pólen/crescimento & desenvolvimento , Zea mays/embriologia , Zea mays/genética
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