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1.
J Agric Food Chem ; 67(38): 10764-10773, 2019 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-31487158

RESUMO

It has been hypothesized that the α-methylene-γ-lactone moiety of sesquiterpene lactones is a key unit for their bioactivity. As a consequence, modifications of these compounds have been focused on this fragment. In the work reported here, two sesquiterpene lactones, namely, dehydrocostuslactone and ß-cyclocostunolide, a eudesmanolide obtained by controlled cyclization of costunolide, were chosen for modification by Michael addition at C-13. On applying this reaction to both compounds, it was possible to introduce the functional groups alkoxy, amino, carbamoyl, hydroxy, and thiol to give products in good to high yields, depending on the base and solvent employed. In particular, the introduction of a thiol group at C-13 in both compounds was achieved with outstanding yields (>90%) and this is unprecedented for these sesquiterpene lactones. The bioactivities of the products were evaluated on etiolated wheat coleoptile elongation and germination of seeds of parasitic weeds, with significant activity observed on Orobanche cumana and Phelipanche ramosa. The structure-activity relationships are discussed.


Assuntos
Lactonas/química , Orobanchaceae/química , Orobanche/química , Extratos Vegetais/química , Plantas Daninhas/química , Sesquiterpenos/química , Germinação , Estrutura Molecular , Orobanchaceae/crescimento & desenvolvimento , Orobanche/crescimento & desenvolvimento , Plantas Daninhas/crescimento & desenvolvimento , Sementes/química , Sementes/crescimento & desenvolvimento , Compostos de Sulfidrila/química
2.
J Agric Food Chem ; 67(35): 9697-9704, 2019 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-31403787

RESUMO

In higher plants, seed size is an important parameter and agricultural trait in many aspects of evolutionary fitness. The loss of water-deficiency-induced crop yield is the largest among all natural hazards. Under water-deficient stress, the most prevalent response to terminal stress is to accelerate the early arrest of floral development and, thereby, to accelerate fruit/seed production, which consequently reduces seed size. This phenomenon is well-known, but its molecular mechanism is not well-reviewed and characterized. However, increasing evidence have indicated that water-deficient stress is always coordinated with three genetic signals (i.e., seed size regulators, initial seed size, and fruit number) that decide the final seed size. Here, our review presents new insights into the mechanism underlying cross-talk water-deficient stress signaling with three genetic signals controlling final seed size. These new insights may aid in preliminary screening, identifying novel genetic factors and future design strategies, or breeding to increase crop yield.


Assuntos
Sementes/citologia , Água/metabolismo , Secas , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Sementes/genética , Sementes/crescimento & desenvolvimento , Sementes/metabolismo , Estresse Fisiológico , Água/análise
3.
Plant Mol Biol ; 101(1-2): 183-202, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31286324

RESUMO

KEY MESSAGE: Isoforms of 2-OGDH E1 subunit are not functionally redundant in plant growth and development of A. thaliana. The tricarboxylic acid cycle enzyme 2-oxoglutarate dehydrogenase (2-OGDH) converts 2-oxoglutarate (2-OG) to succinyl-CoA concomitant with the reduction of NAD+. 2-OGDH has an essential role in plant metabolism, being both a limiting step during mitochondrial respiration as well as a key player in carbon-nitrogen interactions. In Arabidopsis thaliana two genes encode for E1 subunit of 2-OGDH but the physiological roles of each isoform remain unknown. Thus, in the present study we isolated Arabidopsis T-DNA insertion knockout mutant lines for each of the genes encoding the E1 subunit of 2-OGDH enzyme. All mutant plants exhibited substantial reduction in both respiration and CO2 assimilation rates. Furthermore, mutant lines exhibited reduced levels of chlorophylls and nitrate, increased levels of sucrose, malate and fumarate and minor changes in total protein and starch levels in leaves. Despite the similar metabolic phenotypes for the two E1 isoforms the reduction in the expression of each gene culminated in different responses in terms of plant growth and seed production indicating distinct roles for each isoform. Collectively, our results demonstrated the importance of the E1 subunit of 2-OGDH in both autotrophic and heterotrophic tissues and suggest that the two E1 isoforms are not functionally redundant in terms of plant growth in A. thaliana.


Assuntos
Arabidopsis/enzimologia , Carbono/metabolismo , Complexo Cetoglutarato Desidrogenase/metabolismo , Nitrogênio/metabolismo , Arabidopsis/genética , Arabidopsis/crescimento & desenvolvimento , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Dióxido de Carbono/metabolismo , Clorofila/metabolismo , Complexo Cetoglutarato Desidrogenase/genética , Mitocôndrias/enzimologia , Mutagênese Insercional , Nitratos/metabolismo , Fenótipo , Filogenia , Folhas de Planta/enzimologia , Folhas de Planta/genética , Folhas de Planta/crescimento & desenvolvimento , Isoformas de Proteínas , Subunidades Proteicas , Plântula/enzimologia , Plântula/genética , Plântula/crescimento & desenvolvimento , Sementes/enzimologia , Sementes/genética , Sementes/crescimento & desenvolvimento
4.
J Agric Food Chem ; 67(29): 8096-8106, 2019 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-31260296

RESUMO

Field experiments were conducted on wheat to study the effects of foliar-applied iodine(I) alone, Zn (zinc) alone, and a micronutrient cocktail solution containing I, Zn, Se (selenium), and Fe (iron) on grain yield and grain concentrations of micronutrients. Plants were grown over 2 years in China, India, Mexico, Pakistan, South Africa, and Turkey. Grain-Zn was increased from 28.6 mg kg-1 to 46.0 mg-1 kg with Zn-spray and 47.1 mg-1 kg with micronutrient cocktail spray. Foliar-applied I and micronutrient cocktail increased grain I from 24 µg kg-1 to 361 µg kg-1 and 249 µg kg-1, respectively. Micronutrient cocktail also increased grain-Se from 90 µg kg-1 to 338 µg kg-1 in all countries. Average increase in grain-Fe by micronutrient cocktail solution was about 12%. The results obtained demonstrated that foliar application of a cocktail micronutrient solution represents an effective strategy to biofortify wheat simultaneously with Zn, I, Se and partly with Fe without yield trade-off in wheat.


Assuntos
Biofortificação/métodos , Produção Agrícola/métodos , Iodo/metabolismo , Ferro/metabolismo , Selênio/metabolismo , Triticum/metabolismo , Zinco/metabolismo , China , Fertilizantes/análise , Índia , Iodo/análise , Ferro/análise , México , Micronutrientes/análise , Micronutrientes/metabolismo , Paquistão , Folhas de Planta/química , Folhas de Planta/metabolismo , Sementes/química , Sementes/crescimento & desenvolvimento , Sementes/metabolismo , Selênio/análise , África do Sul , Triticum/química , Triticum/crescimento & desenvolvimento , Turquia , Zinco/análise
5.
BMC Plant Biol ; 19(1): 304, 2019 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-31291882

RESUMO

BACKGROUND: In flowering plants, proper seed development is achieved through the constant interplay of fertilization products, embryo and endosperm, and maternal tissues. Communication between these compartments is supposed to be tightly regulated at their interfaces. Here, we characterize the deposition pattern of an apoplastic lipid barrier between the maternal inner integument and fertilization products in Arabidopsis thaliana seeds. RESULTS: We demonstrate that an apoplastic lipid barrier is first deposited by the ovule inner integument and undergoes de novo cutin deposition following central cell fertilization and relief of the FERTILIZATION INDEPENDENT SEED Polycomb group repressive mechanism. In addition, we show that the WIP zinc-finger TRANSPARENT TESTA 1 and the MADS-Box TRANSPARENT TESTA 16 transcription factors act maternally to promote its deposition by regulating cuticle biosynthetic pathways. Finally, mutant analyses indicate that this apoplastic barrier allows correct embryo sliding along the seed coat. CONCLUSIONS: Our results revealed that the deposition of a cutin apoplastic barrier between seed maternal and zygotic tissues is part of the seed coat developmental program.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/crescimento & desenvolvimento , Lipídeos de Membrana/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Endosperma/genética , Endosperma/crescimento & desenvolvimento , Endosperma/metabolismo , Óvulo Vegetal/genética , Óvulo Vegetal/crescimento & desenvolvimento , Óvulo Vegetal/metabolismo , Sementes/genética , Sementes/crescimento & desenvolvimento , Sementes/metabolismo
6.
BMC Plant Biol ; 19(1): 308, 2019 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-31299895

RESUMO

BACKGROUND: Land preparation is an important component of fragrant rice production. However, the effect of tillage on fragrant rice production is unclear, especially regarding the biosynthesis of 2-acetyl-1-pyrroline (2-AP), which is the main compound of the unique aroma of fragrant rice. This study aimed to explore 2-AP biosynthesis in fragrant rice under different tillage regimes. Three tillage methods were applied in the present study: conventional rotary tillage (CK) as the control, plough tillage (PT), and no-tillage (NT). RESULT: Compared with CK, the PT treatment increased 2-AP content in grain, upregulated the activity of ornithine aminotransferase (OAT) and increased contents of 1-pyrroline and pyrroline-5-carboxylic acid (P5C). Furthermore, the PT treatment increased the grain yield and nitrogen accumulation of fragrant rice. Meanwhile, the 2-AP content in the grain produced under the NT treatment was significantly higher than that in the grain produced under both the PT and CK treatments due to the enhancement of proline content and the activities of proline dehydrogenase (PDH) and △1-pyrroline-5-carboxylic acid synthetase (P5CS). However, the present study observed that the overall production of fragrant rice under NT conditions was inferior due to lower yield, nitrogen accumulation, and anti-oxidative enzymatic activities. Moreover, the organic matter content and soil microorganism quantity increased due to PT and NT treatments. CONCLUSIONS: Compared to CK, PT improved fragrant rice grain yield and nitrogen accumulation and induced an increase in OAT activity and led to an increase in 2-AP concentration. No-tillage also produced increased 2-AP content in grain by enhancing PDH and P5CS activities but limited yields and nitrogen accumulation in fragrant rice.


Assuntos
Oryza/fisiologia , Prolina Oxidase/metabolismo , Pirróis/metabolismo , Odorantes , Oryza/enzimologia , Oryza/genética , Oryza/crescimento & desenvolvimento , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Prolina/análise , Prolina Oxidase/genética , Sementes/enzimologia , Sementes/genética , Sementes/crescimento & desenvolvimento , Sementes/fisiologia
7.
J Agric Food Chem ; 67(31): 8441-8451, 2019 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-31339045

RESUMO

The increase in the atmospheric CO2 concentration is predicted to influence wheat production and grain quality and nutritional properties. In the present study, durum wheat (Triticum durum Desf. cv. Sula) was grown under two different CO2 (400 versus 700 µmol mol-1) concentrations to examine effects on the crop yield and grain quality at different phenological stages (from grain filling to maturity). Exposure to elevated CO2 significantly increased aboveground biomass and grain yield components. Growth at elevated CO2 diminished the elemental N content as well as protein and free amino acids, with a typical decrease in glutamine, which is the most represented amino acid in grain proteins. Such a general decrease in nitrogenous compounds was associated with altered kinetics of protein accumulation, N remobilization, and N partitioning. Our results highlight important modifications of grain metabolism that have implications for its nutritional quality.


Assuntos
Dióxido de Carbono/metabolismo , Sementes/crescimento & desenvolvimento , Triticum/metabolismo , Aminoácidos/química , Aminoácidos/metabolismo , Dióxido de Carbono/análise , Cinética , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Sementes/química , Sementes/metabolismo , Triticum/química , Triticum/crescimento & desenvolvimento
8.
J Sci Food Agric ; 99(13): 6049-6059, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31342530

RESUMO

BACKGROUND: The scarcity of irrigation water is severely affecting global crop production. In this context, biostimulants are increasingly used as alternatives means against abiotic stress conditions. In this study, phenolic compounds composition and bioactive properties of common bean (Phaseolus vulgaris L.) plants grown under water stress conditions and biostimulants application were investigated. RESULTS: Sixteen individual phenolic compounds were detected in both pods and seeds with a notable difference in their compositional profile. A significant effect on phenolic compounds content and composition was also observed for the biostimulants tested. Regarding the antibacterial activity, pods of the second harvest and seed extracts showed significant efficacy against Bacillus cereus, especially in water-stressed plants, where all biostimulant treatments were more effective than positive controls. Moreover, all biostimulant treatments for seed extracts of water-stressed plants were more effective against Staphylococcus aureus compared with ampicillin, whereas streptomycin showed the best results. Extracts from pods of the second harvest from normally irrigated plants showed the best results against the fungi tested, except for Penicillium verrucosum var. cyclopium. Finally, no significant cytotoxic effects were detected. CONCLUSION: In conclusion, the biostimulants tested increased total phenolic compounds content compared with control treatment, especially in pods of the first harvest and seeds of water-stressed plants. Moreover, bioactive properties showed a varied response in regard to irrigation and biostimulant treatment. Therefore, biostimulants can be considered as a useful means towards increasing phenolic compounds content, and they may also affect the antimicrobial properties of pods and seeds extracts. © 2019 Society of Chemical Industry.


Assuntos
Desidratação , Phaseolus/química , Phaseolus/fisiologia , Fenóis/farmacologia , Extratos Vegetais/farmacologia , Água/metabolismo , Bacillus cereus/efeitos dos fármacos , Bacillus cereus/crescimento & desenvolvimento , Phaseolus/crescimento & desenvolvimento , Phaseolus/microbiologia , Fenóis/química , Fenóis/metabolismo , Extratos Vegetais/química , Extratos Vegetais/metabolismo , Sementes/química , Sementes/crescimento & desenvolvimento , Sementes/metabolismo , Sementes/microbiologia , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/crescimento & desenvolvimento , Estresse Fisiológico , Água/análise
9.
Plant Cell Rep ; 38(9): 1165-1180, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31161264

RESUMO

KEY MESSAGE: Arabidopsis photorespiratory gene AtAGT1 is important for the growth and development of root, the non-photosynthetic organ, and it is involved in a complex metabolic network and salt resistance. AtAGT1 in Arabidopsis encodes an aminotransferase that has a wide range of donor:acceptor combinations, including Asn:glyoxylate. Although it is one of the photorespiratory genes, its encoding protein has been suggested to function also in roots to metabolize Asn. However, experimental data are still lacking. In this study, we investigated experimentally the function of AtAGT1 in roots and our results uncovered its importance in root development during seedling establishment after seed germination. Overexpression of AtAGT1 in roots promoted both the growth of primary root and outgrowth of lateral roots. To further elucidate the molecular mechanisms underlying, amino acid content and gene expression in roots were analyzed, and results revealed that AtAGT1 is involved in a complex metabolic network and salt resistance of roots.


Assuntos
Ácido Abscísico/metabolismo , Proteínas de Arabidopsis/metabolismo , Arabidopsis/genética , Reguladores de Crescimento de Planta/metabolismo , Arabidopsis/crescimento & desenvolvimento , Arabidopsis/fisiologia , Proteínas de Arabidopsis/genética , Expressão Gênica , Germinação , Plantas Geneticamente Modificadas , Tolerância ao Sal , Plântula/genética , Plântula/crescimento & desenvolvimento , Plântula/fisiologia , Sementes/genética , Sementes/crescimento & desenvolvimento , Sementes/fisiologia , Transaminases/genética , Transaminases/metabolismo
10.
J Sci Food Agric ; 99(12): 5601-5605, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31149731

RESUMO

BACKGROUND: Microgreens (i.e. tender immature greens) are a popular alternative to sprouts (i.e. germinating seeds) because of their higher content of vitamins, carotenoids and phenols, as well as their lower content of nitrates. Their nutritional value can be improved by biofortification, which increases micronutrient levels during plant growth. Because selenium (Se) plays a significant role in antioxidant defense, biofortification with Se is a good way of improving the nutritional quality of sprouts and microgreens. The present study investigated the production of Se-fortified microgreens from Se-enriched seeds of sweet basil (Ocimum basilicum L.). These microgreens could be used as new beneficial dietary supplements. RESULTS: Basil plants were grown in a nutrient solution, containing 0 (control), 4 or 8 mg Se L-1 as sodium selenate, to full maturity. Seeds accumulated a high amount of Se and were then used to produce microgreens. The germination index was higher in the seeds from Se-treated plants and the microgreens were enriched in Se. The antioxidant capacity of Se-fortified microgreens was higher compared to the control. CONCLUSION: The production of microgreens from Se-enriched seeds could comprise a good system for obtaining microgreens with a high nutritional value. Basil plants treated with Se could be used to produce both Se-fortified leaves and microgreens. © 2019 Society of Chemical Industry.


Assuntos
Ocimum basilicum/química , Selênio/análise , Antioxidantes/análise , Antioxidantes/metabolismo , Biofortificação , Fertilizantes/análise , Alimentos Fortificados/análise , Germinação , Valor Nutritivo , Ocimum basilicum/crescimento & desenvolvimento , Ocimum basilicum/metabolismo , Fenóis/análise , Fenóis/metabolismo , Folhas de Planta/química , Folhas de Planta/metabolismo , Sementes/química , Sementes/crescimento & desenvolvimento , Sementes/metabolismo , Selênio/metabolismo
11.
Environ Monit Assess ; 191(7): 465, 2019 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-31243568

RESUMO

The germination capacity of poplar seeds has never been studied in the context of metal(loid)-contaminated soils, even though poplars are present over a vast geographical area. In this study, black poplar seeds from the Loire Valley (France) were grown for 28 days in mesocosm on a heavily polluted soil that was subjected to different amendments. This phytomanagement process aimed to allow the revegetation of an As and Pb-contaminated mining soil by adding appropriate amendments, resulting in metal(loid) soil stabilisation and efficient plant growth. The objectives were to evaluate the effect of three amendments (garden soil, compost and biochar) when added alone or combined to a technosol on (i) the soil physicochemical properties, (ii) the mobility of As and Pb in the soil pore water (SPW), (iii) the capacity of poplar seeds to germinate and to grow and (iv) the metal(loid) distribution within the plant organs. The addition of amendments alone or combined allowed a 90% decrease in SPW Pb concentrations, while the arsenic concentrations were between 18 and 416 times higher. However, we were only able to obtain seed germination and plant growth on amended soils. These promising results will allow us to explore the use of such amendments in rehabilitating areas that are sources of significant metal(loid) dissemination, as well as allowing a natural plant recolonisation of these sites by seeds from the surrounding environment.


Assuntos
Carvão Vegetal/química , Compostagem , Germinação/efeitos dos fármacos , Mineração , Populus/efeitos dos fármacos , Poluentes do Solo/análise , Solo/química , Arsênico/análise , Monitoramento Ambiental , França , Chumbo/análise , Chumbo/toxicidade , Populus/crescimento & desenvolvimento , Sementes/efeitos dos fármacos , Sementes/crescimento & desenvolvimento , Poluentes do Solo/toxicidade
12.
Microbiol Res ; 223-225: 1-12, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31178042

RESUMO

Phosphorus (P) is an essential plant nutrient, but often limited in soils for plant uptake. A major economic constraint in the rice production is excessive use of chemical fertilizers to meet the P requirement. Bioaugmentation of phosphate solubilizing rhizobacteria (PSB) can be used as promising alternative. In the present study 11 mineral PSB were isolated from Basmati rice growing areas of Pakistan. In broth medium, PSB solubilized tricalcium phosphate (27-354 µg mL-1) with concomitant decrease in pH up to 3.6 due to the production of different organic acids, predominantly gluconic acid. Of these, 4 strains also have ability to mineralize phytate (245-412 µg mL-1). Principle component analysis showed that the gluconic acid producing PSB strains (Acinetobacter sp. MR5 and Pseudomonas sp. MR7) have pronounced effect on grain yield (up to 55%), plant P (up to 67%) and soil available P (up to 67%), with 20% reduced fertilization. For simultaneous validation of gluconic acid production by MR5 and MR7 through PCR, new specific primers were designed to amplify gcd, pqqE, pqqC genes responsible for glucose dehydrogenase (gcd) mediated phosphate solubilization. These findings for the first time demonstrated Acinetobacter soli as potent P solubilizer for rice and expands our knowledge about genus specific pqq and gcd primers. These two gcd containing PSB Acinetobacter sp. MR5 (DSM 106631) and Pseudomonas sp. MR7 (DSM 106634) submitted to German culture collection (DSMZ), serve as global valuable pool to significantly increase the P uptake, growth and yield of Basmati rice with decreased dependence on chemical fertilizer in P deficit agricultural soils.


Assuntos
Biofortificação , Glucose 1-Desidrogenase/genética , Oryza/crescimento & desenvolvimento , Fósforo/metabolismo , Acinetobacter/genética , Agricultura , Bactérias/crescimento & desenvolvimento , Bactérias/isolamento & purificação , Bactérias/metabolismo , Proteínas de Bactérias/genética , Transporte Biológico , Meios de Cultura , Fertilizantes , Germinação , Gluconatos/metabolismo , Concentração de Íons de Hidrogênio , Paquistão , Fosfatos/metabolismo , Pseudomonas/genética , Sementes/crescimento & desenvolvimento , Solo/química , Microbiologia do Solo , Solubilidade
13.
Microbiol Res ; 223-225: 33-43, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31178049

RESUMO

Mangroves, dominating tropical intertidal zones and estuaries, are among the most salt tolerant plants, and propagate through reproductive units called propagules. Similarly to plant seeds, propagules may harbor beneficial bacteria. Our hypothesis was that mangroves, being able to grow into seawater, should harbor bacteria able to interact with the host and to exert positive effects under salt stress, which could be exploited to improve crop production. Therefore, we isolated bacterial endophytes from mangrove propagules with the aim to test whether these bacteria have a beneficial potential on their natural host and on different crops such as barley and rice, cultivated under salt stress. The 172 bacterial isolates obtained were screened for plant growth promotion (PGP) activities in vitro, and the 12 most promising isolates were tested on barley under non-axenic conditions and salt stress. Gordonia terrae KMP456-M40 was the best performing isolate, increasing ear weight by 65%. Based on the in vivo PGP activity and the root colonization ability, investigated by fluorescence in situ hybridization and confocal microscopy, three strains were additionally tested on mangrove propagule germination and on rice growth. The most effective strain was again G. terrae KMP456-M40, which enhanced the root length of mangrove seedlings and the biomass of salt-stressed rice under axenic conditions up to 65% and 62%, respectively. We demonstrated that propagules, the reproductive units of mangroves, host beneficial bacteria that enhance the potential of mangrove seedlings establishment and confer salt tolerance to cereal crops.


Assuntos
Produtos Agrícolas , Grão Comestível/crescimento & desenvolvimento , Endófitos/fisiologia , Desenvolvimento Vegetal , Estresse Salino , Bactérias/classificação , Bactérias/isolamento & purificação , Biomassa , Endófitos/classificação , Endófitos/crescimento & desenvolvimento , Endófitos/isolamento & purificação , Genótipo , Germinação , Hordeum/crescimento & desenvolvimento , Hordeum/microbiologia , Hibridização in Situ Fluorescente , Oryza/microbiologia , Pressão Osmótica , Raízes de Plantas/microbiologia , Salinidade , Tolerância ao Sal , Plantas Tolerantes a Sal/microbiologia , Arábia Saudita , Água do Mar , Plântula/crescimento & desenvolvimento , Plântula/microbiologia , Sementes/crescimento & desenvolvimento , Sementes/microbiologia , Microbiologia do Solo , Áreas Alagadas
14.
BMC Plant Biol ; 19(1): 279, 2019 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-31242858

RESUMO

BACKGROUND: Seed germination, a complex, physiological-morphogenetic process, is a critical stage in the life cycle of plants. Biological changes in germinating seeds have not been investigated in poplar, a model woody plant. RESULTS: In this study, we exploited next-generation sequencing and metabolomics analysis and uncovered a series of significantly different genes and metabolites at various stages of seed germination and post germination. The K-means method was used to identify multiple transcription factors, including AP2/EREBP, DOF, and YABBY, involved in specific seed germination and post-germination stages. A weighted gene coexpression network analysis revealed that cell wall, amino acid metabolism, and transport-related pathways were significantly enriched during stages 3 and 5, with no significant enrichment observed in primary metabolic processes such as glycolysis and the tricarboxylic acid cycle. A metabolomics analysis detected significant changes in intermediate metabolites in these primary metabolic processes, while a targeted correlation network analysis identified the gene family members most relevant to these changing metabolites. CONCLUSIONS: Taken together, our results provide important insights into the molecular networks underlying poplar seed germination and post-germination processes. The targeted correlation network analysis approach developed in this study can be applied to search for key candidate genes in specific biochemical reactions and represents a new strategy for joint multiomics analyses.


Assuntos
Germinação , Proteínas de Plantas/genética , Populus/genética , Sementes/crescimento & desenvolvimento , Fatores de Transcrição/genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Germinação/genética , Proteínas de Plantas/metabolismo , Populus/crescimento & desenvolvimento , Sementes/genética , Fatores de Transcrição/metabolismo
15.
J Plant Physiol ; 239: 61-70, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31200171

RESUMO

Seeds are the basis of propagation for the common beech (Fagus sylvatica L.), but the seed set of the beech is unsteady, with 5-10 years between abundant crops. Beech seeds are very difficult to store and lose their viability quickly even in optimum storage conditions. To date, it has not been possible to determine factors indicative of the aging process and the loss of viability of beech seeds during storage. To address this important economic challenge and interesting scientific problem, we analyzed the adjustment of the redox state during the development and storage of seeds. Many metabolic processes are based on reduction and oxidation reactions. Thiol proteins control and react to the redox state in the cells. The level of thiol proteins increased during seed maturation and decreased during storage. Gel-based redox proteomics identified 17 proteins in beech seeds during development. The proteins could be assigned to processes like metabolism and antioxidant functions. During storage, the number of proteins decreased to only six, i.e., oxidoreductases, peptidases, hydrolases and isomerases. The occurrence of peroxiredoxins (PRX) as thiol peroxidases and redox regulators indicates an important role of cytosolic 1CysPRX and PRXIIC, mitochondrial PRXIIF, and plastidic PRXIIE, 2CysPRX, and PRXQ in beech seeds during development and storage. Particularly, 2CysPRX was present in beech seeds during development and storage and may perform an important function in regulation of the redox state during both seed development and storage. The role of thiol proteins in the regulation of the redox state during the development and storage of beech seeds is discussed.


Assuntos
Fagus/metabolismo , Sementes/metabolismo , Compostos de Sulfidrila/metabolismo , Fagus/crescimento & desenvolvimento , Germinação , Oxirredução , Peroxirredoxinas/metabolismo , Proteínas de Plantas/metabolismo , Sementes/crescimento & desenvolvimento
16.
J Plant Physiol ; 239: 71-82, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31212099

RESUMO

Cryopreservation is a process whereby biological structures are preserved in liquid nitrogen (-196 °C) without losing their viability. Many cryopreservation techniques use the Plant Vitrification Solution 2 (PVS2) for cryoprotection. This study will therefore evaluate the influence of different exposure times to the cryoprotectant PVS2 and discuss the importance of the mobilization of reserves and the antioxidant metabolism during the germination of cryopreserved Passiflora ligularis embryos. The composition of P. ligularis seeds was analytically determined. We tested the germination capacity and the Germination Speed Index (GSI) of embryos (that is, seeds without external tegument) which were exposed to different PVS2 exposure times (0, 30, 60 and 120 min) at 30 days after thawing. Proline content, hydrogen peroxide, activity of isocitrate lyase (ICL), malate synthase (MSy), lipid peroxidation and antioxidant enzyme activities (SOD, CAT, APX) were measured at 7, 14 and 21 days after cryopreservation. The germination from cryopreserved embryos was maximal (85%) after 60 min PVS2 exposure with a GSI of 0.6. At 60 min, the highest activity of the enzymes involved in the glyoxylate cycle, ICL and MSy were recorded. We hypothesize that a 60 min exposure to PVS2 accelerates the reserve mobilization which correlates positively with germination. Until 60 min, there was a positive correlation between the PVS2 exposure time and the proline content, as well as the activity of antioxidant enzymes (SOD, CAT, APX), and a negative correlation with the lipid peroxidation. This study enables us to optimize the long-term conservation of this species. In conclusion, fundamental research is necessary to optimize the cryopreservation procedure, and this study offers an effective and efficient workflow which can be extrapolated to other (oil-rich) species.


Assuntos
Antioxidantes/metabolismo , Crioprotetores/metabolismo , Germinação/efeitos dos fármacos , Metabolismo dos Lipídeos/efeitos dos fármacos , Passiflora/fisiologia , Sementes/efeitos dos fármacos , Criopreservação , Sementes/crescimento & desenvolvimento
17.
Planta ; 250(2): 657-665, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31147828

RESUMO

MAIN CONCLUSION: The grapevine VvßVPE promoter is specifically expressed in the seed. The - 1306~- 1045 bp core region restricts expression in other tissues and organs. Vacuolar processing enzyme (VPE) is a cysteine proteinase regulating vacuolar protein maturation and executing programmed cell death (PCD) in plants. Vitis vinifera (Vv)ßVPE is a ß-type VPE showing seed-specific expression that processes seed proteins during ovule development. However, the regulation of the seed-specific gene expression is far from understood. In this study, we characterize VvßVPE promoter (pVvßVPE) from 12 seeded and seedless grape genotypes. 94.56% of the pVvßVPE coding sequence is consistent. Two ßVPE promoters were constructed and transformed into Arabidopsis thaliana via ß-glucuronidase (GUS) fused expression vectors, using cv. Pinot Noir and cv. Thompson as seed and seedless candidates. GUS staining in different tissues and organs revealed that VvßVPE expresses specifically in the embryo, including the cotyledon, hypocotyl and suspensor, but not in the leaf, stem, root or flowers of the seedling. Using promoter deletion analysis, we created four incomplete VvßVPE promoters and found each pVvßVPE deletion could drive GUS gene to express in seeds. Interestingly, seed specificity disappeared when the promoter missed the core - 1306~- 1045 bp region. All deletion promoters presenting various quantified GUS activities indicate that the region - 1704~- 1306 bp inhibits, and the region - 705~- 861 bp promotes gene expression of VvßVPE. Our results demonstrate that pVvßVPE is a seed-specific promoter in both seeded and seedless grapes. Moreover, the core region of pVvßVPE (- 1306~- 1045 bp) is the key one responsible for seed-specific expression.


Assuntos
Cisteína Endopeptidases/genética , Regiões Promotoras Genéticas/genética , Sementes/genética , Vitis/genética , Arabidopsis/genética , Arabidopsis/crescimento & desenvolvimento , Clonagem Molecular , Regulação da Expressão Gênica de Plantas , Genes Reporter , Especificidade de Órgãos , Óvulo Vegetal/genética , Óvulo Vegetal/crescimento & desenvolvimento , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas , Plântula/genética , Plântula/crescimento & desenvolvimento , Sementes/crescimento & desenvolvimento , Vitis/crescimento & desenvolvimento
18.
Nat Commun ; 10(1): 2555, 2019 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-31186418

RESUMO

Functional traits are expected to modulate plant competitive dynamics. However, how traits and their plasticity in response to contrasting environments connect with the mechanisms determining species coexistence remains poorly understood. Here, we couple field experiments under two contrasting climatic conditions to a plant population model describing competitive dynamics between 10 annual plant species in order to evaluate how 19 functional traits, covering physiological, morphological and reproductive characteristics, are associated with species' niche and fitness differences. We find a rich diversity of univariate and multidimensional associations, which highlight the primary role of traits related to water- and light-use-efficiency for modulating the determinants of competitive outcomes. Importantly, such traits and their plasticity promote species coexistence across climatic conditions by enhancing stabilizing niche differences and by generating competitive trade-offs between species. Our study represents a significant advance showing how leading dimensions of plant function connect to the mechanisms determining the maintenance of biodiversity.


Assuntos
Adaptação Fisiológica , Clima , Magnoliopsida/crescimento & desenvolvimento , Fenômenos Fisiológicos Vegetais , Biodiversidade , Ecossistema , Magnoliopsida/fisiologia , Modelos Teóricos , Fenótipo , Sementes/crescimento & desenvolvimento
19.
Food Chem ; 295: 579-587, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31174798

RESUMO

Chemical composition, thermal, pasting, and moisture adsorption properties of flours from chickpea (Cicer aretinium L.), lentil (Lens culinaris Merr.), and yellow pea (Pisum sativum L.) were investigated over a 6-day germination. Protein content increased for pulses over germination while lentil had the highest protein content that increased from 30.65 to 33.60 g/100 g dry basis (d.b.). Lipid content in pulse flours decreased over germination with chickpea having the greatest decline, i.e. from 8.00 to 5.90 g/100 g (d.b.). Total starch decreased in lentil and yellow pea flours during germination, while there was no significant change (p > 0.05) in germinated chickpea flours. Thermal properties of pulse flours changed slightly, while pasting properties varied among pulses. The highest final viscosities for chickpea, lentil, and yellow pea flours were 1061, 981, and 1052 cP and were observed after 2, 1, and 0 days of germination, respectively. Moisture adsorption isotherms showed improved water adsorption capability after germination.


Assuntos
Cicer/metabolismo , Farinha/análise , Lens (Planta)/metabolismo , Ervilhas/metabolismo , Adsorção , Cicer/crescimento & desenvolvimento , Germinação , Lens (Planta)/crescimento & desenvolvimento , Lipídeos/análise , Tamanho da Partícula , Ervilhas/crescimento & desenvolvimento , Sementes/crescimento & desenvolvimento , Sementes/metabolismo , Água/química
20.
Plant Sci ; 285: 122-131, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31203876

RESUMO

Domestication and subsequent breeding have eroded genetic diversity in the modern chickpea crop by ˜100-fold. Corresponding reductions to trait variation create the need, and an opportunity, to identify and harness the genetic capacity of wild species for crop improvement. Here we analyze trait segregation in a series of wild x cultivated hybrid populations to delineate the genetic underpinnings of domestication traits. Two species of wild chickpea, C. reticulatum and C. echinospermum, were crossed with the elite, early flowering C. arietinum cultivar ICCV96029. KASP genotyping of F2 parents with an FT-linked molecular marker enabled selection of 284 F3 families with reduced phenological variation: 255 F3 families of C. arietinum x reticulatum (AR) derived from 17 diverse wild parents and 29 F3 families of C. arietinum x echinospermum (AE) from 3 wild parents. The combined 284 lineages were genotyped using a genotyping-by-sequencing strategy and phenotyped for agronomic traits. 50 QTLs in 11 traits were detected from AR and 35 QTLs in 10 traits from the combined data. Using hierarchical clustering to assign traits to six correlated groups and mixed model based multi-trait mapping, four pleiotropic loci were identified. Bayesian analysis further identified four inter-trait relationships controlling the duration of vegetative growth and seed maturation, for which the underlying pleiotropic genes were mapped. A random forest approach was used to explore the most extreme trait differences between AR and AE progenies, identifying traits most characteristic of wild species origin. Knowledge of the genomic basis of traits that segregate in wild-cultivated hybrid populations will facilitate chickpea improvement by linking genetic and phenotypic variation in a quantitative genetic framework.


Assuntos
Cicer/genética , Genes de Plantas/genética , Melhoramento Vegetal/métodos , Teorema de Bayes , Cicer/crescimento & desenvolvimento , DNA de Plantas/genética , Domesticação , Estudos de Associação Genética , Ligação Genética/genética , Hibridização Genética/genética , Locos de Características Quantitativas/genética , Característica Quantitativa Herdável , Sementes/crescimento & desenvolvimento
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